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Table of Contents

As filed with the Securities and Exchange Commission on November 8, 2018

Registration No. 333-[            ]

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

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FORM S-4
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

PACWEST BANCORP
(Exact name of registrant as specified in its charter)

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9701 Wilshire Boulevard, Suite 700
Beverly Hills, California 90212
(310) 887-8500
(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant's Principal Executive Offices)

Kori L. Ogrosky
Executive Vice President, General Counsel and Corporate Secretary
9701 Wilshire Boulevard, Suite 700
Beverly Hills, California 90212
(310) 887-8500
(Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)

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Approximate date of commencement of proposed sale of the securities to the public:
As soon as practicable after this registration statement becomes effective and upon completion of the merger.

           If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box:    o

           If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

           If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. o

           If applicable, place an ý in the box to designate the appropriate rule provision relied upon in conducting this transaction:

           Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer) o

           Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer) o

CALCULATION OF REGISTRATION FEE

(1)

Represents the maximum number of shares of PacWest Bancorp common stock estimated to be issuable in the transaction described herein, based on an amount equal to the product of (i) 139,685.5 shares of El Dorado common stock outstanding as of October 31, 2018 and (ii) 58.2209.

(2)

Estimated solely for the purpose of determining the registration fee required by Section 6(b) of the Securities Act and calculated in accordance with Rules 457(f)(2) and 457(f)(3) of the Securities Act of 1933, based on the value of shares of El Dorado common stock expected to be exchanged for PacWest Bancorp common stock in connection with the merger, as established by the book value per share of El Dorado common stock as of October 31, 2018 of $1,673.85, less the estimated cash consideration to be paid in the merger.

(3)

Computed pursuant to Rules 457(f)(2) and 457(f)(3) of the Securities Act, based on a rate of $121.20 per $1,000,000 of the proposed maximum aggregate offering price.

           The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

   

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Information contained herein is subject to completion or amendment. A registration statement relating to the shares of PacWest Bancorp common stock to be issued in the merger has been filed with the Securities and Exchange Commission. These securities may not be sold, nor may offers to buy be accepted, prior to the time the registration statement becomes effective. This proxy statement/prospectus shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any jurisdiction in which such offer, solicitation or sale is not permitted or would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction.

PRELIMINARY PROXY STATEMENT/PROSPECTUS
DATED NOVEMBER 8, 2018, SUBJECT TO COMPLETION

Dear Shareholder:

        You are cordially invited to attend a special meeting of the shareholders of El Dorado Savings Bank, F.S.B., a federal savings association, which is referred to as El Dorado, which we will hold at our executive offices, 4040 El Dorado Road, Placerville, California 95667, on [            ], [2018][2019], at 10:00 a.m., local time. At the special meeting, holders of El Dorado common stock will be asked to approve the merger of El Dorado with and into Pacific Western Bank, a California state-chartered bank and wholly-owned subsidiary of PacWest Bancorp, which is referred to as PacWest, with Pacific Western Bank as the surviving bank, which is referred to as the merger, pursuant to the Agreement and Plan of Merger, which is referred to as the merger agreement, dated as of September 11, 2018, by and between PacWest and El Dorado, which proposal is referred to as the merger proposal.

        At the effective time of the merger, each share of El Dorado common stock, other than certain specified excluded shares and dissenting shares, will be converted into the right to receive (i) $427.92 in cash and (ii) 58.2209 shares of PacWest common stock, referred to as the exchange ratio, with cash paid in lieu of a fractional share of PacWest common stock, which collectively is referred to as the merger consideration, which will be subject to certain adjustments as described in this proxy statement/prospectus in the sections entitled "The Merger Agreement—Merger Consideration" and "The Merger Agreement—Termination of the Merger Agreement." The merger agreement provides that El Dorado may terminate the merger agreement if (i) the volume weighted average price of PacWest common stock for the 20 consecutive trading days ending on the date that is five business days prior to the closing date, which period is referred to as the determination period, falls below $42.80 per share and (ii) the volume weighted average price of PacWest common stock over the determination period underperforms the average KBW Regional Banking Index, referred to as the KBW Index, for the determination period by more than 15%. If El Dorado elects to exercise such termination right, then PacWest may reinstate the agreement after increasing the exchange ratio or cash consideration according to formulas set forth in the merger agreement such that the value of the merger consideration would be at least equal to $2,919.77 per share, as adjusted for any decline in the KBW Index. For a more complete discussion of the termination rights, including the formulas for determining the value of the merger consideration if PacWest reinstates the agreement, please refer to the section of this proxy statement/prospectus entitled "The Merger Agreement—Termination of the Merger Agreement."

        The market value of the stock portion of the merger consideration will fluctuate with the price of PacWest common stock. Based on the closing price of PacWest common stock on September 11, 2018, the last trading day before the public announcement of the signing of the merger agreement, the value of the per share merger consideration payable to holders of shares of El Dorado common stock was $3,341.29. Based on the closing price of PacWest common stock on [            ], 2018, the last practicable date before the date of this proxy statement/prospectus, the value of the per share merger consideration payable to holders of shares of El Dorado common stock was $[            ]. You should obtain current price quotations for PacWest common stock. PacWest common stock is traded on NASDAQ under the symbol "PACW."

        The merger is intended to qualify, and the obligation of PacWest and El Dorado to complete the merger is conditioned upon the receipt of legal opinions from their respective counsel to the effect that the merger will qualify, as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code. In such case, you generally will recognize gain (but not loss) upon receipt of the merger consideration in exchange for shares of El Dorado common stock in the merger in an amount equal to the lesser of (1) the amount of gain realized (i.e., the excess of the sum of the amount of cash and the fair market value of the PacWest common stock received pursuant to the merger over your adjusted tax basis in the shares of El Dorado common stock surrendered in the exchange) and (2) the amount of cash received pursuant to the merger (excluding any cash received in lieu of a fractional share of PacWest common stock).

        The board of directors of El Dorado has unanimously approved the merger agreement and the transactions contemplated thereby, and determined that the merger agreement and the transactions

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contemplated thereby are fair to and in the best interests of El Dorado and its shareholders. The board of directors recommends that the El Dorado shareholders vote "FOR" the merger proposal.

        At the special meeting, El Dorado shareholders will also be asked to vote on a proposal to approve one or more adjournments of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to approve the merger proposal, which is referred to as the adjournment proposal. The board of directors recommends that the El Dorado shareholders vote "FOR" the adjournment proposal.

        Your vote is very important. To ensure your representation at the special meeting, please complete and return the enclosed proxy card or submit your proxy by telephone or through the Internet. Whether or not you expect to attend the special meeting, please vote promptly. Submitting a proxy now will not prevent you from being able to vote in person at the special meeting.

        If you hold your shares in "street name" through a broker, bank or other nominee, you should follow the directions provided by your broker, bank or other nominee regarding how to instruct your broker, bank or other nominee to vote your shares. Without those instructions, your shares will not be voted, which will have the same effect as voting against the merger proposal and will result in your shares not being counted as represented for purposes of establishing a quorum at the special meeting, which would affect the outcome of the vote on the adjournment proposal if such failure to provide instructions prevented a quorum from being established.

        This proxy statement/prospectus provides you with detailed information about the proposed merger. You are encouraged to read the entire proxy statement/prospectus, including the appendices and the documents incorporated by reference, carefully. In particular, you should read the "Risk Factors" section beginning on page 26 for a discussion of the risks you should consider in evaluating the proposed merger and how it will affect you.

        We thank you for your continued support and look forward to seeing you at the special meeting.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the merger, the issuance of the PacWest Bancorp common stock in connection with the merger or the other transactions described in this document, or passed upon the adequacy or accuracy of the disclosures in this document. Any representation to the contrary is a criminal offense.

        The securities to be issued in connection with the merger are not savings accounts, deposits or other obligations of any bank or savings association and are not insured by the Federal Deposit Insurance Corporation or any other governmental agency.

        If you have any questions or need assistance in voting your shares, please call George L. Cook, Jr., Chief Executive Officer of El Dorado, at (530) 622-1492.

        This document is dated [            ], 2018 and is first being mailed to El Dorado shareholders on or about [            ], 2018.

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WHERE YOU CAN FIND MORE INFORMATION

PacWest Bancorp

        PacWest Bancorp, referred to as PacWest, files annual, quarterly and special reports, proxy statements and other business and financial information with the Securities and Exchange Commission, referred to as the SEC. PacWest files reports and other business and financial information with the SEC electronically, and the SEC maintains a website located at http://www.sec.gov containing this information. You may also obtain these documents, free of charge, from PacWest at www.pacwestbancorp.com under the "Public Filings" link.

        PacWest has filed a registration statement on Form S-4 of which this document forms a part. As permitted by SEC rules, this document does not contain all of the information included in the registration statement or in the exhibits or schedules to the registration statement. You may read and copy the registration statement, including any amendments, schedules and exhibits, at the addresses set forth below. Statements contained in this document as to the contents of any contract or other documents referred to in this document are not necessarily complete. In each case, you should refer to the copy of the applicable contract or other document filed as an exhibit to the registration statement. This document incorporates by reference documents that PacWest has previously filed with the SEC. They contain important information about PacWest and its financial condition. For more information, please see the section entitled "Incorporation of Certain Documents by Reference." These documents are available without charge to you upon written or oral request to PacWest's principal executive offices. The address and telephone number of PacWest's principal executive office is listed below.

PacWest Bancorp
9701 Wilshire Boulevard, Suite 700
Beverly Hills, California 90212
Attention: Investor Relations
(310) 887-8500

        PacWest common stock is traded on the NASDAQ Global Select Market under the symbol "PACW." The NASDAQ Global Select Market is referred to herein as the NASDAQ.

El Dorado Savings Bank, F.S.B.

        El Dorado Savings Bank, F.S.B., referred to as El Dorado, does not have a class of securities registered under Section 12 of the Exchange Act, is not subject to the reporting requirements of Section 13(a) or 15(d) of the Exchange Act and, accordingly, does not file documents and reports with the SEC.

        If you are an El Dorado shareholder and have any questions concerning the merger, the merger agreement or the prospectus/proxy, would like additional copies of the prospectus/ proxy without charge or need help voting your shares of El Dorado common stock, please contact George L. Cook, Jr., Chief Executive Officer of El Dorado, at (530) 622-1492 or at the following address:

        El Dorado Savings Bank, F.S.B.
4040 El Dorado Road
Placerville, California 95667
Attention: Corporate Secretary

        To obtain timely delivery of these documents, you must request the information no later than [            ], [2018][2019] in order to receive them before El Dorado's special meeting of shareholders.

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El DORADO SAVINGS BANK, F.S.B.
4040 EL DORADO ROAD
PLACERVILLE, CALIFORNIA 95667

NOTICE OF THE SPECIAL MEETING OF SHAREHOLDERS
TO BE HELD ON [            ], [2018][2019]

        NOTICE IS HEREBY GIVEN that a special meeting of the shareholders of El Dorado Savings Bank, F.S.B., referred to as El Dorado, will be held at our executive offices, 4040 El Dorado Road, Placerville, California 95667, on [            ], [2018][2019], at 10:00 a.m., local time, which is referred to as the special meeting, for the purpose of considering and voting upon the following proposals:

        1.     Merger Proposal.    To approve the merger of El Dorado with and into Pacific Western Bank pursuant to the Agreement and Plan of Merger, dated as of September 11, 2018, by and between PacWest Bancorp and El Dorado, as such agreement may be amended from time to time, a copy of which is attached as Appendix A to this proxy statement/prospectus; and

        2.     Adjournment Proposal.    To approve one or more adjournments of the special meeting, if necessary or appropriate, including adjournments to permit further solicitation of proxies if there are insufficient votes at the time of the special meeting to approve the merger proposal.

        El Dorado will transact no other business at the special meeting other than as listed above.

        The El Dorado board of directors has set [            ], 2018 as the record date for the special meeting. Only holders of record of shares of El Dorado common stock at the close of business on [            ], 2018 will be entitled to notice of and to vote at the special meeting and any adjournments or postponements thereof.

        Approval of the merger proposal requires the affirmative vote of two-thirds of the outstanding shares of El Dorado common stock entitled to vote thereon at the special meeting.

        The El Dorado board of directors has unanimously approved the merger agreement and the transactions contemplated thereby and recommends that you vote "FOR" the merger proposal and "FOR" the adjournment proposal.

        Your vote is very important.    To ensure your representation at the special meeting, please (1) complete, sign, date and return the enclosed proxy card in the envelope provided or (2) follow the instructions provided on the proxy card to submit your proxy by telephone or through the Internet. If you hold your shares through a bank, broker or other nominee, you should direct the vote of your shares in accordance with the voting instructions received from your bank, broker or other nominee. Please vote promptly whether or not you expect to attend the special meeting.

        If you plan to attend the special meeting, you will be required to bring certain documents with you to be admitted to the meeting. Please read carefully the sections in the proxy statement/prospectus regarding attending and voting at the special meeting to ensure that you comply with these requirements. You are encouraged to read the entire proxy statement/prospectus, including the appendices and the documents incorporated by reference, carefully. If you have any questions about the proposals or need assistance in voting your shares, please call George L. Cook, Jr., Chief Executive Officer of El Dorado, at (530) 622-1492.

        In connection with the merger, El Dorado shareholders will have the opportunity to exercise dissenters' rights in accordance with the procedures set forth in 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a. Copies of 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a are attached to this proxy statement/prospectus as Appendix C. A dissenting shareholder who votes "AGAINST" the merger proposal or who gives notice in writing to El Dorado at or prior to the special meeting that such holder dissents from the merger and who follows the required procedures may receive cash in an amount equal to the value of his or her shares of El Dorado common stock in lieu of the merger consideration provided for under the merger agreement. For additional details and information on how to exercise your dissenters' rights, please refer to "The Merger—Dissenters' Rights" on page 70 and Appendix C of this proxy statement/prospectus. Failure to follow all of the steps required under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a will result in the loss of your dissenters' rights.

BY ORDER OF THE BOARD OF DIRECTORS

John A. Cook
President, Chief Operating Officer and Corporate Secretary
Placerville, California
[            ], 2018

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QUESTIONS AND ANSWERS ABOUT THE SPECIAL MEETING

        The following are answers to certain questions that you may have regarding the special meeting of shareholders of El Dorado Savings Bank, F.S.B., which is referred to as the special meeting. You should carefully read the remainder of this document because the information in this section may not provide all the information that might be important to you in determining how to vote. Additional important information is also contained in the appendices to, and the documents incorporated by reference in, this document.

Q:

WHAT IS THE MERGER?

A.

PacWest Bancorp, a Delaware corporation, referred to as PacWest, and El Dorado Savings Bank, F.S.B., a federal savings association, referred to as El Dorado, have entered into an agreement and plan of merger, which is referred to as the merger agreement, pursuant to which and subject to the terms and conditions of the merger agreement, El Dorado will merge with and into Pacific Western Bank, a California state-chartered bank and wholly-owned subsidiary of PacWest, with Pacific Western Bank continuing as the surviving bank, which transaction is referred to as the merger. A copy of the merger agreement is attached as Appendix A to this document. In order to complete the merger, among other conditions described in the merger agreement and this proxy statement/prospectus, the El Dorado shareholders and the applicable banking regulators must approve the merger.

Q:

WHY AM I RECEIVING THIS PROXY STATEMENT/PROSPECTUS?

A.

El Dorado is sending these materials to its shareholders to help them decide how to vote their shares of El Dorado common stock with respect to the merger and other matters to be considered at the special meeting.

The merger cannot be completed unless El Dorado shareholders approve the merger. El Dorado is holding a special meeting of its shareholders to vote on the proposal to approve the merger as well as other related matters. Information about this special meeting, the merger and the other business to be considered by shareholders at the special meeting is contained in this document.

This document constitutes both a proxy statement of El Dorado and a prospectus of PacWest. It is a proxy statement because the El Dorado board of directors is soliciting proxies from El Dorado shareholders using this document with respect to the matters to be considered at the special meeting. It is a prospectus because PacWest, in connection with the merger, is offering shares of its common stock in exchange for outstanding shares of El Dorado common stock in the merger.

Q:

WHAT WILL EL DORADO SHAREHOLDERS RECEIVE IN THE MERGER?

A:

In the merger, each share of El Dorado common stock owned by an El Dorado shareholder, other than certain specified excluded shares and dissenting shares, will be converted into the right to receive (i) $427.92 in cash, referred to as the cash consideration, and (ii) 58.2209 shares of PacWest common stock, par value $0.01 per share, referred to as PacWest common stock, which ratio is referred to as the exchange ratio, subject to adjustment as set forth in the merger agreement and as further described below and in the following question and answer and in the sections entitled "The Merger Agreement—Merger Consideration" and "The Merger Agreement—Termination of the Merger Agreement." The cash consideration and PacWest common stock to be exchanged for each share of El Dorado common stock are referred to collectively as the merger consideration. For each fractional share that would otherwise be issued, PacWest will pay cash in an amount equal to the fraction of a share (rounded to the nearest thousandth) of PacWest common stock which the holder would otherwise be entitled to receive multiplied by the volume weighted average price of PacWest common stock as quoted on the NASDAQ over the 20

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consecutive trading days ending on the fifth business day immediately prior to the closing date. No interest will be paid or accrue on cash payable to holders in lieu of fractional shares.

The fifth business day immediately prior to the closing date is referred to as the price determination date; the 20 consecutive trading day period ending on the price determination date is referred to as the determination period; and the volume weighted average price of shares of PacWest common stock quoted on NASDAQ for the determination period is referred to as the PacWest average closing price.

The merger consideration may be subject to adjustment if certain title defects and/or environmental conditions exist with respect to El Dorado's real property and the total cost to cure and/or remediate such defects or conditions (after taking into account any tax credits, deductions or benefits or insurance coverage, in each case, that the parties agree are reasonably likely to be available) is greater than $2,000,000, which excess is referred to as the real property adjustment amount. In that case, the aggregate cash consideration will be reduced by the real property adjustment amount, except that if the real property adjustment amount exceeds $7,000,000, which excess is referred to as the excess adjustment amount, then in lieu of reducing the cash consideration by 100% of the excess adjustment amount, the merger consideration will be reduced as follow: (i) 12.5% of the excess adjustment amount will be applied to reduce the aggregate cash consideration; and (ii) the remaining 87.5% of the excess adjustment amount will be applied to reduce the stock portion of the merger consideration by reducing the exchange ratio accordingly. If the real property adjustment amount exceeds $15,000,000 (unless PacWest agrees that the real property adjustment amount will be $15,000,000), El Dorado may terminate the merger agreement. If the real property adjustment amount exceeds $25,000,000, PacWest may terminate the merger agreement.

Based on the closing price of PacWest common stock on September 11, 2018, the last trading day before the public announcement of the signing of the merger agreement, the value of the per share merger consideration payable to holders of El Dorado common stock was $3,341.29. Based on the closing price of PacWest common stock on [            ], 2018, the last practicable date before the date of this document, the value of the per share merger consideration payable to holders of shares of El Dorado common stock was $[            ].

Q:

WILL THE VALUE OF THE MERGER CONSIDERATION CHANGE BETWEEN THE DATE OF THIS DOCUMENT AND THE TIME THE MERGER IS COMPLETED?

A:

Yes. Although the number of shares of PacWest common stock that El Dorado shareholders will receive in the merger is fixed, other than in the specified circumstances described above and below, the value of the merger consideration will fluctuate between the date of this document and the completion of the merger based upon the market value of PacWest common stock. Any fluctuation in the market price of PacWest common stock after the date of this document will change the value of the shares of PacWest common stock that El Dorado shareholders will receive.

In addition, the merger agreement provides that El Dorado may terminate the merger agreement if:

•

the PacWest average closing price is less than $42.80 per share (with a proportionate adjustment for any stock dividend, reclassification, recapitalization, split-up, combination, exchange of shares or similar transaction between the date of the merger agreement and the price determination date); and



•

the PacWest average closing price underperforms the average price of the KBW Regional Banking Index, referred to as the KBW Index, during the determination period by more than 15%.

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If El Dorado elects to terminate the merger agreement and provides written notice thereof to PacWest, then within two business days following PacWest's receipt of such notice, PacWest may elect to reinstate the merger and related transactions, and adjust the exchange ratio to equal the lesser of (i) the quotient of $2,491.71 divided by the PacWest average closing price and (ii) the quotient of $2,491.71 divided by the PacWest average closing price, multiplied by the index ratio. Alternatively, PacWest may elect not to adjust the exchange ratio, and, in lieu thereof, may increase the cash consideration per share of El Dorado common stock such that the value of the total consideration received for each share is the same as if the exchange ratio had been adjusted as described above.

For more information, please see the section entitled "The Merger Agreement—Termination of the Merger Agreement."

Q:

WHEN WILL THE MERGER BE COMPLETED?

A:

PacWest and El Dorado are working to complete the merger as soon as practicable. The parties are seeking regulatory approval by the first quarter of 2019, with the consummation of the merger to occur as soon as practicable thereafter. Neither PacWest nor El Dorado know, however, the actual date on which the merger will be completed because it is subject to factors beyond each company's control, including whether or when the required regulatory approvals and shareholder approval of the merger proposal, referred to as the El Dorado shareholder approval, will be received. For more information, please see the section entitled "The Merger Agreement—Conditions to Consummation of the Merger."

Q:

WHO IS ENTITLED TO VOTE?

A:

Holders of record of shares of El Dorado common stock at the close of business on [            ], 2018, which is the date that the El Dorado board of directors has fixed as the record date for the special meeting, are entitled to vote at the special meeting.

Q:

WHAT CONSTITUTES A QUORUM?

A:

A majority of the shares entitled to vote, represented in person or by proxy, constitutes a quorum for transacting business at the special meeting. Proxies marked as abstaining on any matter to be acted upon by shareholders will be counted as represented at the meeting for purposes of determining the presence or absence of a quorum.

Q:

WHAT AM I BEING ASKED TO VOTE ON AND WHY IS THIS APPROVAL NECESSARY?

A:

El Dorado shareholders are being asked to vote on the following proposals:

1.

to approve the merger of El Dorado with and into Pacific Western Bank, with Pacific Western Bank as the surviving bank, pursuant to the Agreement and Plan of Merger, dated as of September 11, 2018, by and between PacWest and El Dorado, as such agreement may be amended from time to time, a copy of which is attached as Appendix A, referred to as the merger proposal; and

2.

to approve one or more adjournments of the special meeting, if necessary or appropriate, including adjournments to permit further solicitation of proxies if there are insufficient votes at the time of the special meeting to approve the merger proposal, referred to as the adjournment proposal.

The El Dorado shareholder approval is required to complete the merger. El Dorado will transact no business at the special meeting other than as listed above.

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Q:

WHAT VOTE IS REQUIRED TO APPROVE EACH PROPOSAL AT THE SPECIAL MEETING?

A:

The Merger Proposal:    The merger proposal requires the affirmative vote of two-thirds of the outstanding shares of El Dorado common stock entitled to vote thereon at the special meeting.

The Adjournment Proposal:    The adjournment proposal requires the affirmative vote of the majority of the shares represented at a duly held meeting at which a quorum is present (which shares voting affirmatively also constitute at least a majority of the required quorum).

Q:

ARE THERE ANY VOTING AGREEMENTS WITH EXISTING SHAREHOLDERS?

A:

Yes. Each of the directors of El Dorado, in his capacity as a beneficial owner of any shares of common stock of El Dorado, has entered into a voting agreement with PacWest, the form of which is attached as Appendix B, in which each such director has agreed to vote all shares of El Dorado common stock that he beneficially owns and has the power to vote in favor of the merger proposal and any other matter that is required to be approved by the shareholders of El Dorado to facilitate the transactions contemplated by the merger agreement. The directors also agreed to vote against any proposal made in opposition to the approval of the merger or in competition with the merger agreement and against any acquisition proposal. As of the close of business on the record date, El Dorado's directors beneficially owned, in the aggregate, [            ] shares of El Dorado common stock, allowing them to exercise approximately [            ]% of the voting power of El Dorado common stock.

Q:

WHAT DOES THE EL DORADO BOARD OF DIRECTORS RECOMMEND?

A:

The El Dorado board of directors recommends that El Dorado shareholders vote "FOR" the merger proposal and "FOR" the adjournment proposal.

Q:

WHAT DO I NEED TO DO NOW?

A:

After carefully reading and considering the information contained in this document, please vote your shares of El Dorado common stock as soon as possible so that such shares will be represented at the special meeting. Please follow the instructions set forth on the proxy card or on the voting instruction form provided by the record holder if your shares of El Dorado common stock are held in the name of your broker, bank or other nominee.

Q:

HOW DO I VOTE?

A:

If you are an El Dorado shareholder of record as of the close of business on the record date, you may submit your proxy before the special meeting in one of the following ways:

•

use the telephone number shown on your proxy card;

•

visit the website shown on your proxy card to vote via the Internet; or

•

complete, sign, date and return the enclosed proxy card in the enclosed postage-paid envelope.

You may also cast your vote in person at the special meeting.

If your shares of El Dorado common stock are held in "street name," through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting such shares. "Street name" shareholders who wish to vote at the meeting will need to obtain a proxy form from their broker, bank or other nominee.

Q:

HOW MANY VOTES DO I HAVE?

A:

You are entitled to one vote for each share of El Dorado common stock that you owned as of the close of business on the record date. As of the close of business on the record date, there were

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approximately [            ] outstanding shares of El Dorado common stock entitled to vote. As of that date, approximately [            ]% of such outstanding shares of El Dorado common stock were beneficially owned by the directors and executive officers of El Dorado and their affiliates.

Q:

WHEN AND WHERE IS THE SPECIAL MEETING?

A:

The special meeting will be held at the executive offices of El Dorado, 4040 El Dorado Road, Placerville, California 95667 at 10:00 a.m., local time, on [            ], [2018][2019]. Subject to space availability, all El Dorado shareholders as of the close of business on the record date, or their duly appointed proxies, may attend the special meeting. Since seating may be limited, admission to the special meeting will be on a first-come, first-served basis. Registration and seating will begin at 9:30 a.m., local time.

Q:

IF MY SHARES ARE HELD IN "STREET NAME" BY A BROKER, BANK OR OTHER NOMINEE, WILL MY BROKER, BANK OR OTHER NOMINEE VOTE MY SHARES FOR ME?

A:

If your shares of El Dorado common stock are held in "street name" by a broker, bank or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your broker, bank or other nominee. Please note that you may not vote shares held in "street name" by returning a proxy card directly to El Dorado or by voting in person at the special meeting unless you provide a "legal proxy," which you must obtain from your broker, bank or other nominee.

Brokers who hold shares in "street name" for the beneficial owner of those shares typically have the authority to vote in their discretion on "routine" proposals when they have not received instructions from the beneficial owner. However, brokers are not allowed to exercise their voting discretion with respect to the approval of matters that are "non-routine" without specific instructions from the beneficial owner. Both proposals to be voted on at the special meeting are considered "non-routine" matters and, therefore, brokers, banks and other nominees do not have discretionary voting power on these matters.

If you are an El Dorado shareholder and you do not instruct your broker, bank or other nominee on how to vote your shares, then your broker, bank or other nominee may not vote your shares on either the merger proposal or the adjournment proposal.

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For the merger proposal, shares not represented at the special meeting are still considered outstanding and, therefore, will have the same effect as a vote "AGAINST" the proposal. The merger proposal requires the affirmative vote of two-thirds of the outstanding shares entitled to vote. Therefore, the failure of a holder of shares of El Dorado common stock to provide its bank, broker or other nominee with voting instructions will have the same effect as a vote "AGAINST" the merger proposal.



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The adjournment proposal requires the affirmative vote of the majority of the shares represented at a duly held meeting at which a quorum is present (which shares voting affirmatively also constitute at least a majority of the required quorum). Your bank, broker or other nominee does not have discretionary authority to vote your shares on the special meeting proposals without your instructions. Consequently, failure to provide instructions to your bank, broker or other nominee on how to vote will result in your shares not being counted as represented for purposes of establishing a quorum at the special meeting. Accordingly, such a failure would have an effect on the outcome of the vote if such failure prevented a quorum from being established.

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Q:

WHAT IF I ABSTAIN OR DO NOT VOTE?

A:

For purposes of the special meeting, an abstention occurs when a shareholder attends the special meeting, either in person or represented by proxy, but abstains from voting.

Abstentions will be counted as represented at the special meeting for purposes of determining the presence or absence of a quorum for all matters to be voted on at the special meeting.

For the merger proposal, if an El Dorado shareholder present in person at the special meeting abstains from voting, or responds by proxy with an "abstain" vote, it will have the same effect as a vote cast "AGAINST" the proposal. If an El Dorado shareholder is not present in person at the special meeting and does not respond by proxy, it will also have the same effect as a vote cast "AGAINST" the proposal.

The adjournment proposal requires the affirmative vote of the majority of the shares represented at a duly held meeting at which a quorum is present (which shares voting affirmatively also constitute at least a majority of the required quorum). Accordingly, for purposes of the adjournment proposal, abstentions will affect the outcome as they will be counted as shares represented at the meeting, but not voted affirmatively in favor of the adjournment proposal.

Q:

WHAT WILL HAPPEN IF I RETURN MY PROXY OR VOTING INSTRUCTION CARD WITHOUT INDICATING HOW TO VOTE?

A:

If you hold your shares of El Dorado common stock in your name as a shareholder of record, and you sign and return your proxy card without indicating how to vote on any particular proposal, the shares of El Dorado common stock represented by your proxy will be voted "FOR" the merger proposal and "FOR" the adjournment proposal.

If you hold your shares of El Dorado common stock in "street name" through a broker, bank or other nominee and you do not give your broker, bank or other nominee instructions on how to vote, your broker, bank or other nominee will not be able to vote your shares of El Dorado common stock on either of the proposals at the special meeting and your shares of El Dorado common stock will not be represented at the special meeting. For the merger proposal, shares not represented at the special meeting are still considered outstanding and, therefore, will have the same effect as a vote "AGAINST" the proposal. For purposes of the adjournment proposal, abstentions will affect the outcome as they will be counted as shares represented at the meeting, but not voted affirmatively in favor of the adjournment proposal.

Q:

MAY I CHANGE MY VOTE AFTER I HAVE DELIVERED MY PROXY OR VOTING INSTRUCTION CARD?

A:

Yes. If you hold your shares of El Dorado common stock in your name as a shareholder of record, you may change your vote at any time before your proxy is voted at the special meeting. You may do so in one of four ways:

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first, by sending a notice of revocation stating that you would like to revoke your proxy;

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second, by sending a completed proxy card bearing a later date than your original proxy card;

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third, by logging onto the Internet website specified on your proxy card in the same manner you would submit your proxy electronically or by calling the telephone number specified on your proxy card, in each case if you were eligible to do so and following the instructions on the proxy card; or

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fourth, by attending the special meeting and voting in person. Attendance at the El Dorado special meeting will not in itself constitute the revocation of a proxy.

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If you are an El Dorado shareholder of record and you choose to send a written notice of revocation or to mail a new proxy card, you must submit your notice of revocation or your new proxy to El Dorado's corporate secretary at 4040 El Dorado Road, Placerville, California 95667. Any proxy that you submitted may also be revoked by submitting a new proxy via the Internet or by telephone no later than [        ], [        ], 2018 at 11:59 p.m., Eastern Time, or by voting in person at the special meeting.

If your shares are held in "street name" through a broker, bank or other nominee and you have instructed your nominee how to vote your shares of El Dorado common stock, you must submit new voting instructions to your nominee. You should follow the instructions you receive from your broker, bank or other nominee in order to change or revoke your vote.

Q:

DO I NEED IDENTIFICATION TO ATTEND THE SPECIAL MEETING IN PERSON?

A:

Yes. If you hold your shares of El Dorado common stock in your name as a shareholder of record and you wish to attend the special meeting and vote in person, please bring valid picture identification.

If your shares are held in "street name" through a broker, bank or other nominee, you may only vote in person at the special meeting if you have proof of ownership of your shares of El Dorado common stock as of the record date and obtain a valid legal proxy from your broker, bank or other nominee that is the shareholder of record of such shares and present such items at the special meeting. You must also bring valid picture identification.

Q:

ARE EL DORADO SHAREHOLDERS ENTITLED TO DISSENTERS' RIGHTS?

A:

Under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a, El Dorado shareholders may be entitled to dissenters' rights in connection with the merger. If you do not wish to accept the merger consideration and you (i) vote "AGAINST" the merger in person or by proxy at the special meeting or (ii) have given notice in writing to El Dorado at or prior to the special meeting that you dissent from the merger, you have the right to seek from El Dorado in cash "the value of the shares" in lieu of the mix of cash and PacWest common stock you would receive if the merger is completed. Please refer to the section entitled "The Merger—Dissenters' Rights" and to the applicable provisions of 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a attached as Appendix C for information on how to exercise your dissenters' rights. Failure to follow all of the steps required under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a will result in the loss of your dissenters' rights.

Q:

WHAT ARE THE MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES OF THE MERGER TO U.S. HOLDERS OF SHARES OF EL DORADO COMMON STOCK?

A:

The merger is intended to qualify, and the obligation of PacWest and El Dorado to complete the merger is conditioned upon the receipt of legal opinions from their respective counsel to the effect that the merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code. In such case, you generally will recognize gain (but not loss) upon receipt of the merger consideration in exchange for shares of El Dorado common stock pursuant to the merger in an amount equal to the lesser of (1) the amount of gain realized (i.e., the excess of the sum of the amount of cash and the fair market value of the PacWest common stock received pursuant to the merger over your adjusted tax basis in the shares of El Dorado common stock surrendered in the exchange) and (2) the amount of cash received pursuant to the merger (excluding any cash received in lieu of a fractional share of PacWest common stock).

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For a more detailed discussion of the material U.S. federal income tax consequences of the transaction, please see the section entitled "Material U.S. Federal Income Tax Consequences of the Merger."

The tax consequences of the merger to any particular shareholder will depend on that shareholder's particular facts and circumstances. Accordingly, you are urged to consult your tax advisor to determine your tax consequences from the merger.

Q:

WHAT HAPPENS IF THE MERGER IS NOT COMPLETED?

A:

If the merger is not completed, El Dorado shareholders will not receive any consideration for their shares of El Dorado common stock that otherwise would have been received in connection with the merger. Instead, El Dorado will remain an independent company.

Q:

WHAT HAPPENS IF I SELL MY SHARES OF EL DORADO COMMON STOCK AFTER THE RECORD DATE BUT BEFORE THE SPECIAL MEETING?

A:

The record date of the special meeting is earlier than the date of the special meeting and the date that the merger is expected to be completed. If you sell or otherwise transfer your shares of El Dorado common stock after the record date but before the date of the special meeting, you will retain your right to vote at the special meeting (provided that such shares remain outstanding on the date of the special meeting), but you will not have the right to receive the merger consideration to be received by El Dorado shareholders in the merger. In order to receive the merger consideration, you must hold your shares of El Dorado common stock through completion of the merger.

Q:

WILL I BE ABLE TO SELL THE SHARES OF PACWEST COMMON STOCK THAT I RECEIVE IN THE MERGER?

A:

Yes. You may freely trade the shares of PacWest common stock issued in the merger.

Q:

ARE THERE RISKS INVOLVED IN UNDERTAKING THE MERGER?

A:

Yes. In evaluating the merger, El Dorado shareholders should carefully consider the factors discussed in "Risk Factors" beginning on page 26 and other information about El Dorado and PacWest included in the documents incorporated by reference into this proxy statement/prospectus.

Q:

SHOULD EL DORADO SHAREHOLDERS SEND IN THEIR STOCK CERTIFICATES NOW?

A:

No. El Dorado shareholders SHOULD NOT send in any stock certificates now. If the merger is consummated, transmittal materials with instructions for their completion will be provided to El Dorado shareholders under separate cover and the stock certificates should be sent at that time.

Q:

WHAT SHOULD I DO IF I RECEIVE MORE THAN ONE SET OF VOTING MATERIALS?

A:

El Dorado shareholders may receive more than one set of voting materials, including multiple copies of this document and multiple proxy cards or voting instruction cards. If you are a shareholder of record and your shares are registered in more than one name, you will receive more than one proxy card. If you hold shares of El Dorado common stock in more than one brokerage account, you may receive a separate voting instruction card for each brokerage account in which you hold such shares. In each case, please complete, sign, date and return each proxy card and voting instruction card that you receive or otherwise follow the voting instructions set forth in this document to ensure that you vote every share of El Dorado common stock that you own.

Q:

WHOM SHOULD I CONTACT IF I HAVE ANY QUESTIONS ABOUT THE PROXY MATERIALS OR VOTING?

A:

If you are an El Dorado shareholder and have any questions about the proxy materials or if you need assistance submitting your proxy or voting your shares or need additional copies of this document or the enclosed proxy card, you should contact George L. Cook, Chief Executive Officer of El Dorado, at (530) 622-1492.

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UNAUDITED PER SHARE DATA

        The following table shows per common share data regarding basic and diluted earnings, cash dividends and book value for PacWest on a historical basis.

        The following information has been derived from and should be read in conjunction with PacWest's audited consolidated financial statements at and for the year ended December 31, 2017 and its unaudited consolidated financial statements at and for the nine months ended September 30, 2018, which are incorporated herein by reference. This information is presented for illustrative purposes only. You should not rely on historical information only as it is not necessarily indicative of the operating results or financial position that would have occurred if the merger had been completed, nor is it necessarily indicative of the future operating results or financial position of the combined company.

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COMPARATIVE MARKET INFORMATION

PacWest Information

        PacWest common stock is traded on NASDAQ under the symbol "PACW." As of the latest practicable date before the date of this document, there were [            ] holders of PacWest common stock. You should obtain current price quotations for PacWest common stock.

        The following table sets forth the closing sale prices per share of PacWest common stock on September 11, 2018, the last trading day before the public announcement of the signing of the merger agreement, and on [            ], 2018, the latest practicable date before the date of this document. The following table also includes the equivalent market value per share of El Dorado common stock on September 11, 2018 and [            ], 2018 determined by adding $427.92 in cash plus the product of the share price of PacWest common stock on such dates and the exchange ratio of 58.2209.

El Dorado Information

        There is no established public trading market for shares of El Dorado common stock and no broker makes a market in the stock.

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RISK FACTORS

        In addition to the other information contained in or incorporated by reference into this document, including the matters addressed under the caption entitled "Cautionary Statement Regarding Forward-Looking Statements," El Dorado shareholders should carefully consider the following factors in deciding whether to vote for El Dorado's proposals. Please see the sections entitled "Where You Can Find More Information" and "Incorporation of Certain Documents by Reference."

Because the market price of PacWest common stock will fluctuate, the value of the merger consideration to be received by El Dorado shareholders may change.

        At the effective time of the merger, other than in certain circumstances described below, each share of El Dorado common stock, other than certain specified excluded shares and dissenting shares, will be converted into the right to receive the merger consideration consisting of (i) $427.92 in cash and (ii) 58.2209 shares of PacWest common stock, subject to potential adjustment as described below, with cash paid in lieu of a fractional share of PacWest common stock. Accordingly, the value of the merger consideration to be received by El Dorado shareholders will be based on the value of PacWest common stock at closing. The value of the PacWest common stock to be received by El Dorado shareholders in the merger may vary from the value as of the date the merger was announced, the date that this document was mailed to El Dorado shareholders, the date of the special meeting and the determination period. Any change in the market price of PacWest common stock prior to completion of the merger will affect the value of the merger consideration that El Dorado shareholders will receive upon completion of the merger. Accordingly, at the time of the special meeting, El Dorado shareholders will not know or be able to calculate the value of the per share consideration they would receive upon completion of the merger. Share price changes may result from a variety of factors, including general market and economic conditions, changes in PacWest's or El Dorado's businesses, operations and prospects, and regulatory considerations, among other things. Many of these factors are beyond the control of PacWest and El Dorado. El Dorado shareholders should obtain current market quotations for PacWest common stock before voting their shares at the special meeting. PacWest common stock is traded on NASDAQ under the symbol "PACW."

        Under certain circumstances, if certain title defects and/or environmental conditions exist with respect to El Dorado's real property and the total cost to cure and/or remediate such defects or conditions (after taking into account any tax credits, deductions or benefits or insurance coverage, in each case, that the parties agree are reasonably likely to be available) is greater than $2,000,000, the aggregate cash consideration will be reduced by the real property adjustment amount, except that if the real property adjustment amount exceeds $7,000,000, then in lieu of reducing the cash consideration by 100% of the excess adjustment amount, the merger consideration will be reduced as follow: (i) 12.5% of the excess adjustment amount will be applied to reduce the aggregate cash consideration; and (ii) the remaining 87.5% of the excess adjustment amount will be applied to reduce the stock portion of the merger consideration by reducing the exchange ratio accordingly. If the real property adjustment amount exceeds $15,000,000 (unless PacWest agrees that the real property adjustment amount will be $15,000,000), El Dorado may terminate the merger agreement. If the real property adjustment amount exceeds $25,000,000, PacWest may terminate the merger agreement.

        In addition, the merger agreement provides that El Dorado may terminate the merger agreement if (i) the PacWest average closing price falls below $42.80 per share and (ii) the PacWest average closing price underperforms the average price of the KBW Index during the determination period by more than 15%. If El Dorado elects to terminate the merger agreement, then PacWest may reinstate the agreement after increasing the exchange ratio or cash consideration according to formulas set forth in the merger agreement such that the value of the merger consideration would be at least equal to $2,919.77 per share, as adjusted for any decline in the KBW Index. Accordingly, at the time of the El Dorado special meeting, El Dorado shareholders may not know or be able to calculate the applicable

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metrics over the determination period to determine the cash consideration or the exchange ratio used to determine the number of shares of PacWest common stock they would receive with respect to each share of El Dorado common stock upon completion of the merger, and the number of shares of PacWest common stock or cash consideration to be received by El Dorado shareholders may be materially less than anticipated by El Dorado shareholders.

        For a more detailed discussion of potential adjustments to the merger consideration, see the sections entitled "The Merger Agreement—Merger Consideration" and "The Merger Agreement—Termination of the Merger Agreement."

El Dorado shareholders will have a reduced ownership and voting interest in PacWest after the merger and will exercise less influence over PacWest's management.

        El Dorado shareholders currently have the right to vote in the election of the El Dorado board of directors and on other matters affecting El Dorado. Upon the completion of the merger, except for shareholders who own common shares in both PacWest and El Dorado, each El Dorado shareholder will be a stockholder of PacWest with a percentage ownership of PacWest that is smaller than such shareholder's current percentage ownership of El Dorado. It is currently expected that former shareholders of El Dorado as a group will receive shares in the merger constituting approximately 6.3% of the outstanding shares of PacWest's common stock immediately after the merger. Because of this, El Dorado shareholders will have less influence on the management and policies of PacWest than they now have on the management and policies of El Dorado.

Sales of substantial amounts of PacWest's common stock in the open market by former El Dorado shareholders could decrease PacWest's stock price.

        Shares of PacWest common stock that are issued to El Dorado shareholders in the merger will be freely tradable without restrictions or further registration under the Securities Act. As of the close of business on October 31, 2018, PacWest had approximately 121,770,415 shares of common stock outstanding. Based on the shares of El Dorado common stock currently outstanding, PacWest currently expects to issue approximately 8,132,615 shares of its common stock in connection with the merger.

        Because of the significantly enhanced liquidity of PacWest common stock as compared to shares of El Dorado common stock on account of the fact that PacWest's common stock is publicly traded, if the merger is completed, El Dorado's former shareholders may sell substantial amounts of PacWest common stock in the public market following completion of the merger. Any such sales may cause the market price of PacWest common stock to decrease. These sales might also make it more difficult for PacWest to sell equity or equity-related securities at a time and price that it otherwise would deem appropriate.

PacWest may fail to realize the anticipated benefits of the merger.

        The success of the merger will depend on, among other things, PacWest's ability to combine and integrate the business of El Dorado into Pacific Western Bank's business. If PacWest is not able to successfully achieve this objective, the anticipated benefits of the merger may not be realized fully, or at all, or may take longer to realize than expected.

        PacWest and El Dorado have operated and, until the consummation of the merger, will continue to operate independently. It is possible that the integration process or other factors could result in the loss or departure of key employees, the disruption of the ongoing business of PacWest, Pacific Western Bank or El Dorado or inconsistencies in standards, controls, practices, procedures and policies. It is also possible that clients, customers, depositors and counterparties of El Dorado could choose to discontinue their relationships with PacWest post-merger because they prefer doing business with a different financial institution, which could adversely affect the future anticipated performance of

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PacWest. These transition matters could have an adverse effect on El Dorado during the pre-merger period and the combined company for an undetermined amount of time after the consummation of the merger.

Regulatory approvals may not be received, may take longer than expected or may impose conditions that are not presently anticipated or cannot be met.

        Before the transactions contemplated by the merger agreement, including the merger, may be completed, various approvals must be obtained from bank regulatory authorities. These governmental entities may impose conditions on the granting of such approvals. Such conditions or changes and the process of obtaining regulatory approvals could have the effect of delaying completion of the merger or of imposing additional costs or limitations on PacWest following the merger. The regulatory approvals may not be received at all, may not be received in a timely fashion, and may contain conditions on the completion of the merger that are not anticipated or cannot be met. If the consummation of the merger is delayed, including by a delay in receipt of necessary governmental approvals, the business, financial condition and results of operations of each company may also be materially adversely affected.

Failure of the merger to be completed, the termination of the merger agreement or a significant delay in the consummation of the merger could negatively impact PacWest and El Dorado.

        The merger agreement is subject to a number of conditions which must be fulfilled in order to complete the merger. Those conditions include: (i) approval of the merger by El Dorado shareholders, (ii) absence of any governmental order or law prohibiting completion of the merger or the other transactions contemplated by the merger agreement and (iii) effectiveness of the registration statement of which this document is a part.

        The obligation of each party to consummate the merger is also conditioned upon (i) subject to certain exceptions, the accuracy of the representations and warranties of the other party, (ii) performance in all material respects by the other party of its obligations under the merger agreement, (iii) receipt by each party of a tax opinion to the effect that the merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code and (iv) the absence of a material adverse effect with respect to the other party since the date of the merger agreement. The obligation of PacWest to consummate the merger is also conditioned upon (a) the sum of the adjusted shareholders' equity and allowance for loan losses of El Dorado not being less than a specified level, (b) the receipt of certain required regulatory approvals and such approvals not containing materially burdensome regulatory conditions, (c) El Dorado's average total deposits for the calendar month immediately preceding the closing date not being less than a specified level, (d) holders of not more than 10% of outstanding shares of El Dorado common stock having duly exercised their dissenters' rights under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a and (e) the expiration of all applicable time periods set forth in the merger agreement relating to the determination of the costs associated with any title defects or environmental conditions for each of El Dorado's owned real properties. The obligation of El Dorado to consummate the merger is also conditioned upon the receipt of certain required regulatory approvals and the completion of certain filings with NASDAQ.

        These conditions to the consummation of the merger may not be fulfilled and, accordingly, the merger may not be completed. In addition, if the merger is not completed by the end date, either PacWest or El Dorado may choose not to proceed with the merger, and the parties can mutually decide to terminate the merger agreement at any time, before or after the El Dorado shareholder approval.

        Furthermore, prior to the El Dorado shareholder approval, PacWest may terminate the merger agreement and require payment of a $18,669,000 termination fee if (i) PacWest terminates the merger agreement because El Dorado has breached in any material respect the prohibitions in the merger agreement relating to acquisition proposals; (ii) the El Dorado board of directors has effected a change

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of recommendation; or (iii) at any time following receipt of a public acquisition proposal (other than a tender offer or exchange offer), the El Dorado board of directors has failed to reaffirm its recommendation that the El Dorado shareholders approve the merger as promptly as practicable (but in any event within five business days) after receipt of any written request to do so by PacWest (or, if earlier, by the close of business on the business day immediately preceding the special meeting). El Dorado must also pay the $18,669,000 termination fee if (a) an acquisition proposal has been made to El Dorado or its shareholders generally or any person has publicly announced an intention to make an acquisition proposal with respect to El Dorado; (b) thereafter the merger agreement is terminated by either party because (1) the merger was not consummated on or before the end date and the El Dorado shareholder approval has not been obtained or (2) the El Dorado shareholder approval was not obtained at the special meeting and (c) within 12 months after the termination of the merger agreement, El Dorado enters into a definitive agreement with respect to or consummates an acquisition proposal (except that for purposes of the foregoing, references to "15%" in the definition of the term "acquisition proposal" will instead refer to "50%").

        If the merger is not consummated, the ongoing business, financial condition and results of operations of each party may be materially adversely affected and the market price of PacWest's common stock may decline significantly, particularly to the extent that the current market price of PacWest common stock reflects a market assumption that the merger will be consummated. If the consummation of the merger is delayed, including by the receipt of a competing acquisition proposal, the business, financial condition and results of operations of each company may be materially adversely affected.

        In addition, each party has incurred and will incur substantial expenses in connection with the negotiation and completion of the transactions contemplated by the merger agreement. If the merger is not completed, the parties would have to recognize these expenses, including, in the case of El Dorado under certain circumstances, a termination fee, without realizing the expected benefits of the transaction. Any of the foregoing, or other risks arising in connection with the failure of or delay in consummating the merger, including the diversion of management attention from pursuing other opportunities and the constraints in the merger agreement on each party's ongoing business during the pendency of the merger, could have a material adverse effect on each party's business, financial condition and results of operations.

        Additionally, PacWest's or El Dorado's business may be adversely impacted by the failure to pursue other beneficial opportunities due to the focus of management on the merger, without realizing any of the anticipated benefits of completing the merger, and the market price of PacWest common stock might change to the extent that the current market price reflects a market assumption that the merger will be completed. If the merger agreement is terminated and a party's board of directors seeks another merger or business combination, such party's shareholders cannot be certain that such party will be able to find a third party willing to engage in a transaction on more attractive terms than the merger.

El Dorado will be subject to business uncertainties and contractual restrictions while the merger is pending.

        Uncertainty about the effect of the merger on employees, customers, suppliers and vendors may have an adverse effect on the business, financial condition and results of operations of El Dorado and, consequently, PacWest. These uncertainties and contemplated changes may impair El Dorado's ability to attract, retain and motivate key personnel and customers pending the consummation of the merger, as such personnel and customers may experience uncertainty about their future roles following the consummation of the merger. Additionally, these uncertainties and contemplated changes could cause customers, suppliers, vendors and others who deal with El Dorado to seek to change existing business relationships with El Dorado or fail to extend an existing relationship with El Dorado. In addition,

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competitors may target El Dorado's existing customers by highlighting potential uncertainties and integration difficulties that may result from the merger.

        El Dorado has a small number of key personnel. The pursuit of the merger and the preparation for the integration may place a burden on El Dorado's management and internal resources. Any significant diversion of management attention away from ongoing business concerns and any difficulties encountered in the transition and integration process could have a material adverse effect on El Dorado's business, financial condition and results of operations.

        In addition, the merger agreement restricts El Dorado from taking certain actions without PacWest's consent while the merger is pending. These restrictions may, among other matters, and subject to certain exceptions, prevent El Dorado from pursuing otherwise attractive business opportunities, selling assets, incurring indebtedness, engaging in significant capital expenditures, entering into other transactions or making other changes to El Dorado's business prior to consummation of the merger or termination of the merger agreement. These restrictions could have a material adverse effect on El Dorado's business, financial condition and results of operations. Please see the section entitled "The Merger Agreement—Conduct of Business Prior to the Completion of the Merger" for a description of the restrictive covenants applicable to El Dorado.

El Dorado directors and officers have interests in the merger different from the interests of other El Dorado shareholders.

        El Dorado's executive officers and directors have interests in the merger that are different from, or in addition to, the interests of El Dorado shareholders generally. Such interests include the following: (1) Thomas C. Meuser, Chairman of the Board, George L. Cook, Jr., Chief Executive Officer and a director of El Dorado, and William H. Blucher, Chief Financial Officer and a director of El Dorado, have entered into consulting agreements with PacWest that become effective as of, and are conditioned upon, the closing of the merger; (2) John A. Cook, President and Chief Operating Officer of El Dorado, has entered into an offer letter with PacWest to be employed as a regional president with a start date following, and is conditioned upon, the closing of the merger; (3) each of El Dorado's four executive officers are party to an executive salary continuation agreement with El Dorado that provides for certain benefits upon termination of employment within 36 months following a change in control of El Dorado; and (4) El Dorado directors and officers are entitled to continued indemnification and insurance coverage under the merger agreement.

        These interests are described in more detail under the section entitled "The Merger—Interests of El Dorado Directors and Executive Officers in the Merger."

Shares of PacWest common stock to be received by El Dorado shareholders as a result of the merger will have rights different from shares of El Dorado common stock.

        Upon completion of the merger, the rights of former El Dorado shareholders will be governed by the certificate of incorporation and bylaws of PacWest. The rights associated with shares of El Dorado common stock are different from the rights associated with PacWest common stock. In addition, the rights of stockholders under Delaware law, where PacWest is incorporated, may differ from the rights of shareholders under federal law, under which El Dorado is chartered. Please see the section entitled "Comparison of Shareholders' Rights" for a discussion of the different rights associated with PacWest common stock.

The merger agreement contains provisions that may discourage other companies from trying to acquire El Dorado.

        The merger agreement contains provisions that may discourage a third party from submitting a business combination proposal to El Dorado that might result in greater value to El Dorado

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shareholders than the merger. These provisions include a general prohibition on El Dorado from soliciting, or, subject to certain exceptions, entering into discussions with any third party regarding any acquisition proposal or offers for competing transactions. In addition, in some circumstances upon termination of the merger agreement, El Dorado may be required to pay PacWest a $18,669,000 termination fee. However, the failure of El Dorado shareholders to approve the merger agreement will not in and of itself trigger El Dorado's obligation to pay a termination fee, unless other factors also exist, including a third-party proposal to acquire El Dorado and entry into a definitive agreement with respect to an acquisition of El Dorado, or consummation of an acquisition of El Dorado, in each case within 12 months following termination.

        Each of the directors of El Dorado, in his capacity as a beneficial owner of any shares of common stock of El Dorado, has entered into a voting agreement with PacWest in which each such director has agreed to vote all shares of El Dorado common stock that he beneficially owns and has the power to vote in favor of the merger proposal and any other matter that is required to be approved by the shareholders of El Dorado to facilitate the transactions contemplated by the merger agreement. The directors also agreed to vote against any proposal made in opposition to the approval of the merger or in competition with the merger agreement and against any acquisition proposal. As of the close of business on the record date, El Dorado's directors beneficially owned, in the aggregate, [            ] shares of El Dorado common stock, allowing them to exercise approximately [            ]% of the voting power of shares of El Dorado common stock. For more information, please see the section entitled "The Merger Agreement—Voting Agreements." El Dorado also has an unqualified obligation to submit the merger proposal to a vote of El Dorado shareholders, even if El Dorado receives a proposal that its board of directors believes is superior to the merger.

PacWest expects to incur substantial expenses related to the merger.

        PacWest expects to incur substantial expenses in connection with consummation of the merger and integrating the business, operations, networks, systems, technologies, policies and procedures of El Dorado into that of Pacific Western Bank. Although PacWest and El Dorado have assumed that a certain level of transaction and combination expenses would be incurred, there are a number of factors beyond their control that could affect the total amount or the timing of their combination expenses. Many of the expenses that will be incurred, by their nature, are difficult to estimate accurately at the present time. As a result of these expenses, both PacWest and El Dorado expect to take charges against their earnings before and after the completion of the merger. The charges taken in connection with the merger are expected to be substantial, although the aggregate amount and timing of such charges are uncertain at present.

The opinion of El Dorado's financial advisor will not reflect changes in circumstances between the date of the opinion and the completion of the merger.

        On September 11, 2018, the El Dorado board of directors received an opinion from Sandler, its financial advisor, to the effect that, as of such date and subject to the procedures followed, assumptions made, matters considered and qualifications and limitations on the review undertaken by Sandler as set forth in its opinion, the merger consideration in the proposed merger was fair, from a financial point of view, to the holders of El Dorado common stock. Subsequent changes in the operations and prospects of El Dorado or PacWest, general market and economic conditions and other factors that may be beyond the control of El Dorado or PacWest may significantly alter the value of El Dorado or PacWest or the prices of PacWest common stock or El Dorado common stock by the time the merger is completed. Because El Dorado does not anticipate asking Sandler to update its opinion, the opinion will not address the fairness of the merger consideration from a financial point of view at the time the merger is completed or as of any other date other than the date of such opinion.

        For a description of the opinion that El Dorado received from its financial advisor, please refer to the section entitled "The Merger—Opinion of El Dorado's Financial Advisor."

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        This proxy statement/prospectus contains certain forward-looking information about PacWest, El Dorado, and the combined bank after the close of the merger that is intended to be covered by the safe harbor for "forward-looking statements" provided by the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical fact are forward-looking statements. Such statements involve inherent risks, uncertainties and contingencies, many of which are difficult to predict and are generally beyond the control of PacWest, El Dorado and the combined bank. Readers are cautioned that a number of important factors could cause actual results to differ materially from those expressed in, or implied or projected by, such forward-looking statements. In addition to factors previously disclosed in reports filed by PacWest with the SEC, risks and uncertainties for each institution and the combined institution include, but are not limited to:

•

lower than expected revenues;



•

credit quality deterioration or a reduction in real estate values, which could cause an increase in the provision for credit losses and allowance for credit losses and a reduction in net earnings;



•

increased competitive pressure among depository institutions;



•

the ability to complete the merger, including obtaining required regulatory approvals and approval by the shareholders of El Dorado, or any future transaction, and to integrate such acquired entity or entities successfully or achieve expected beneficial synergies and/or operating efficiencies, in each case within expected time-frames or at all;



•

the reaction by El Dorado's or PacWest's customers, employees and counterparties to the merger;



•

changes in the stock price of PacWest prior to the completion of the merger as a result of the financial performance of PacWest prior to closing;



•

the possibility that regulatory approvals will not be received on expected timeframes or at all;



•

the possibility that personnel changes/retention will not proceed as planned;



•

the possibility that a change in the interest rate environment may increase funding costs and reduce net interest margins;



•

higher than anticipated operating expenses;



•

the effectiveness of PacWest's risk management framework;



•

asset/liability re-pricing risks and liquidity risks;



•

the costs and effects of legal, compliance, and regulatory actions, changes and developments, including the impact of adverse judgments or settlements in litigation;



•

the initiation and resolution of regulatory or other governmental inquiries or investigations, and/or the results of regulatory examinations or reviews;



•

general economic conditions, either nationally or in the market areas in which the entities operate or anticipate doing business, which may be less favorable than expected; and



•

other risk factors described in documents filed by PacWest with the SEC.

        All forward-looking statements included in this proxy statement/prospectus are based on information available at the time of the proxy statement/prospectus. Pro forma, projected and estimated numbers are used for illustrative purposes only and are not forecasts, and actual results may differ materially.

        PacWest and El Dorado are under no obligation to (and expressly disclaim any such obligation to) update or alter these forward-looking statements, whether as a result of new information, future events or otherwise except as required by law.

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EL DORADO SPECIAL MEETING OF SHAREHOLDERS

Date, Time and Place

        The special meeting will be held at El Dorado's principal executive offices, at 4040 El Dorado Road, Placerville, California 95667, on [            ], [2018][2019], at 10:00 a.m., local time. On or about [            ], 2018, El Dorado commenced mailing of this proxy statement/prospectus and the enclosed form of proxy to its shareholders entitled to vote at the special meeting.

Purpose of the Special Meeting

        At the special meeting, El Dorado shareholders will be asked to consider and vote upon the following proposals:

•

Merger Proposal.  To approve the merger of El Dorado with and into Pacific Western Bank, with Pacific Western Bank as the surviving bank, pursuant to the merger agreement, dated as of September 11, 2018, by and between PacWest and El Dorado, as such agreement may be amended from time to time, a copy of which is attached as Appendix A to this proxy statement/prospectus; and



•

Adjournment Proposal.  To approve one or more adjournments of the special meeting, if necessary or appropriate, including adjournments to permit further solicitation of proxies if there are insufficient votes at the time of the special meeting to approve the merger proposal.

        El Dorado will transact no other business at the special meeting other than as listed above.

Recommendation of the El Dorado Board of Directors

        After careful consideration, the El Dorado board of directors has unanimously approved the merger agreement and the transactions contemplated thereby, and determined that the merger agreement and the transactions contemplated thereby are fair to and in the best interests of El Dorado and its shareholders.

        The El Dorado board of directors recommends that you vote "FOR" the merger proposal and "FOR" the adjournment proposal. Please see the section entitled "The Merger—Recommendation of the El Dorado Board of Directors and Reasons for the Merger."

Record Date and Quorum

        The El Dorado board of directors has fixed the close of business on [            ], 2018 as the record date for determining the holders of shares of El Dorado common stock entitled to receive notice of and to vote at the special meeting.

        As of the close of business on the record date, there were [            ] shares of El Dorado common stock outstanding and entitled to vote at the special meeting held by approximately [            ] shareholders of record. Each share of El Dorado common stock entitles the holder to one vote on each proposal to be considered at the special meeting.

        A majority of shares entitled to vote, represented in person or by proxy, constitutes a quorum for transacting business at the special meeting. Abstentions will be counted as represented at the special meeting for purposes of determining the presence or absence of a quorum for all matters voted on at the special meeting.

        None of the proposals to be voted on at the El Dorado special meeting are routine matters for which brokers may have discretionary authority to vote. Consequently, failure to provide instructions to your bank, broker or other nominee on how to vote will result in your shares not being counted as represented for purposes of establishing a quorum at the special meeting. Accordingly, such a failure

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would have an effect on the outcome of the vote if such failure prevented a quorum from being established. Please see "—Shares Held in 'Street Name"' below for further information.

        As of the close of business on the record date, directors and executive officers of El Dorado owned and were entitled to vote [            ] shares of El Dorado common stock, representing approximately [            ]% of the shares of El Dorado common stock outstanding on that date. As of the close of business on the record date, PacWest beneficially held no shares of El Dorado common stock.

        In connection with the merger agreement, each of the directors of El Dorado, in his capacity as a beneficial owner of any shares of common stock of El Dorado, has entered into a voting agreement with PacWest in which each such director has agreed to vote all shares of El Dorado common stock that he beneficially owns and has the power to vote in favor of the merger proposal and any other matter that is required to be approved by the shareholders of El Dorado to facilitate the transactions contemplated by the merger agreement. The directors also agreed to vote against any proposal made in opposition to the approval of the merger or in competition with the merger agreement and against any acquisition proposal. As of the close of business on the record date, El Dorado's directors beneficially owned, in the aggregate, [            ] shares of El Dorado common stock, allowing them to exercise approximately [            ]% of the voting power of shares of El Dorado common stock.

Required Vote

•

Merger Proposal:  The merger proposal requires the affirmative vote of two-thirds of the outstanding shares of El Dorado common stock entitled to vote thereon at the special meeting.



•

Adjournment Proposal:  The adjournment proposal requires the affirmative vote of the majority of the shares represented at a duly held meeting at which a quorum is present (which shares voting affirmatively also constitute at least a majority of the required quorum).

Treatment of Abstentions; Failure to Vote

        For purposes of the special meeting, an abstention occurs when an El Dorado shareholder attends the special meeting, either in person or represented by proxy, but abstains from voting.

        Abstentions will be counted as represented at the special meeting for purposes of determining the presence or absence of a quorum for all matters voted on at the special meeting.

•

For the merger proposal, if an El Dorado shareholder present in person at the special meeting abstains from voting, or responds by proxy with an "abstain" vote, it will have the same effect as a vote "AGAINST" the proposal. If an El Dorado shareholder is not present in person at the special meeting and does not respond by proxy, it will also have the same effect as a vote "AGAINST" the proposal.



•

The adjournment proposal requires the affirmative vote of the majority of the shares represented at a duly held meeting at which a quorum is present (which shares voting affirmatively also constitute at least a majority of the required quorum). Accordingly, for purposes of the adjournment proposal, abstentions will affect the outcome as they will be counted as shares represented at the meeting, but not voted affirmatively in favor of the adjournment proposal.

Voting on Proxies; Incomplete Proxies

        Giving a proxy means that a shareholder authorizes the persons named in the proxy to vote such holder's shares at the special meeting in the manner such holder directs. An El Dorado shareholder may vote by proxy or in person at the special meeting.

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        The method of voting by proxy differs for shares held by shareholders of record and shares held in "street name."

Shareholders of Record:

        If your shares of El Dorado common stock are registered directly in your name, you are considered the shareholder of record with respect to these shares. If you hold your shares in your name as a shareholder of record, you may submit your proxy before the special meeting in one of the following ways:

•

By telephone: Use the telephone number shown on your proxy card. Use any touch-tone telephone to vote your proxy 24 hours a day, 7 days a week. Have your proxy card handy when you call. You will be prompted to enter your control number(s), which is located on your proxy card, and then follow the directions given.



•

Through the Internet: Visit the website shown on your proxy card to vote via the Internet. Use the Internet to vote your proxy 24 hours a day, 7 days a week. Have your proxy card handy when you access the website. You will be prompted to enter your control number(s), which is located on your proxy card, to create and submit an electronic ballot.



•

By mail: Complete, sign, date and return the proxy card in the enclosed envelope. The envelope requires no additional postage if mailed in the United States.

        You may also cast your vote in person at the special meeting. Please see "—Attending the Special Meeting and Voting in Person" below for further information.

        El Dorado requests that El Dorado shareholders vote by telephone, over the Internet or by completing, dating and signing the accompanying proxy and returning it to El Dorado as soon as possible in the enclosed postage-paid envelope. When the accompanying proxy is returned properly executed, the shares of El Dorado common stock represented by it will be voted at the special meeting in accordance with the instructions contained on the proxy card. Electronic proxies submitted via the Internet or by telephone must be received no later than [            ], [            ], [2018][2019] at 11:59 p.m., Eastern Time.

        If you hold your shares of El Dorado common stock in your name as a shareholder of record, and you sign and return your proxy card without indicating how to vote on any particular proposal, the shares of El Dorado common stock represented by the proxy will be voted "FOR" the merger proposal and "FOR" the adjournment proposal.

Shares Held in "Street Name":

        If your shares of El Dorado common stock are held in an account with a bank, broker or other nominee, which are referred to as shares held in "street name," the bank, broker or other nominee is considered the shareholder of record with respect to these shares and you are the beneficial owner of these "street name" shares.

        If your shares are held in "street name" through a broker, bank or other nominee, you will receive instructions from your broker, bank or other nominee that you must follow in order to vote your shares. You should refer to the voting form used by that firm to determine whether you may vote by telephone, Internet or mail.

        If your shares are held in "street name," El Dorado recommends that you mark, date, sign and promptly mail the voting instruction form provided by your bank, broker or other nominee in accordance with the instructions provided by such nominee. If you do not give your bank, broker or other nominees instructions on how to vote your shares of El Dorado common stock, your bank, broker

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or other nominees will not be able to vote your shares on either of the proposals at the special meeting and your shares will not be represented at the special meeting.

        If your shares are held in "street name" through a broker, bank or other nominee you must either direct your nominee on how to vote your shares or obtain a proxy from such nominee to vote in person at the El Dorado special meeting. If your shares are held in "street name," you may only vote in person at the El Dorado special meeting if you have proof of ownership of your shares of El Dorado common stock as of the record date and obtain a valid legal proxy from your bank, broker or other nominee that is the shareholder of record of such shares and present such items at the El Dorado special meeting. Please see "—Attending the Special Meeting and Voting in Person" below for further information.

        Every shareholder's vote is important. Accordingly, each El Dorado shareholder should promptly submit a proxy, whether or not the shareholder plans to attend the special meeting.

        If you are a shareholder of record and your shares are registered in more than one name, you will receive more than one proxy card. If you hold your shares in more than one brokerage account, you may receive a separate voting instruction card for each brokerage account in which you hold shares. In each case, please complete, sign, date and return each proxy card and voting instruction form that you receive.

Shares Held in "Street Name"

        If your shares of El Dorado common stock are held in "street name" through a bank, broker or other nominee, you must provide the bank, broker or other nominee, as the shareholder of record of your shares, with instructions on how to vote your shares. Please follow the instructions provided by your bank, broker or other nominee. You may not vote shares held in "street name" by returning a proxy card directly to El Dorado or by voting in person at the special meeting unless you provide a "legal proxy," which you must obtain from your broker, bank or other nominee.

        Brokers, banks or other nominees who hold shares in "street name" for the beneficial owner are not allowed to vote with respect to the approval of matters that are "non-routine" without specific instructions from the beneficial owner. Both proposals to be voted on at the El Dorado special meeting are considered "non-routine" matters and, therefore, brokers, banks and other nominees do not have discretionary voting power on these matters. A "broker non-vote" occurs on an item when (i) a bank, broker or other nominee has discretionary authority to vote on one or more proposals to be voted on at a meeting of shareholders, but is not permitted to vote on other proposals without instructions from the beneficial owner of the shares and (ii) the beneficial owner fails to provide the bank, broker or other nominee with such instructions. Because none of the proposals to be voted on at the El Dorado special meeting are routine matters for which brokers may have discretionary authority to vote, if you do not instruct your bank, broker or other nominee on how to vote your shares of El Dorado common stock, your bank, broker or other nominee may not vote such shares on either the merger proposal or the adjournment proposal.

        Accordingly, if your shares of El Dorado common stock are held in "street name" and you do not instruct your broker, bank or other nominee on how to vote your shares, then your bank, broker or other nominee will NOT be able to vote your shares of El Dorado common stock on either the merger proposal or the adjournment proposal.

•

For the merger proposal, shares not represented at the special meeting are still considered outstanding and, therefore, will have the same effect as a vote "AGAINST" the proposal. The merger proposal requires the affirmative vote of two-thirds of the outstanding shares of El Dorado common stock entitled to vote thereon at the special meeting. Therefore, the failure of

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a holder of shares of El Dorado common stock to provide its bank, broker or other nominee with voting instructions will have the same effect as a vote "AGAINST" the merger proposal.

•

The adjournment proposal requires the affirmative vote of the majority of the shares represented at a duly held meeting at which a quorum is present (which shares voting affirmatively also constitute at least a majority of the required quorum). Your bank, broker or other nominee does not have discretionary authority to vote your shares on the special meeting proposals without your instructions. Consequently, failure to provide instructions to your bank, broker or other nominee on how to vote will result in your shares not being counted as represented for purposes of establishing a quorum at the special meeting. Accordingly, such a failure would have an effect on the outcome of the vote if such failure prevented a quorum from being established.

Revocability of Proxies and Changes to a Shareholder's Vote

        If you hold your shares of El Dorado common stock in your name as a shareholder of record, you may change your vote at any time before your proxy is voted at the special meeting. You may do this in one of four ways:

•

first, by sending a notice of revocation stating that you would like to revoke your proxy;



•

second, by sending a completed proxy card bearing a later date than your original proxy card;



•

third, by logging onto the Internet website specified on your proxy card in the same manner you would submit your proxy electronically or by calling the telephone number specified on your proxy card, in each case if you were eligible to do so and following the instructions on the proxy card; or



•

fourth, by attending the special meeting and voting in person. Attendance at the El Dorado special meeting will not in itself constitute the revocation of a proxy.

        If you are an El Dorado shareholder of record and you choose to send a written notice of revocation or to mail a new proxy card, you must submit your notice of revocation or your new proxy to El Dorado's corporate secretary at 4040 El Dorado Road, Placerville, California 95667. Any proxy that you submitted may also be revoked by submitting a new proxy via the Internet or by telephone no later than [            ], [            ], [2018][2019] at 11:59 p.m., Eastern Time, or by voting in person at the special meeting.

        If your shares are held in "street name" through a broker, bank or other nominee and you have instructed your nominee how to vote your shares of El Dorado common stock, you must submit new voting instructions to your nominee. You should follow the instructions you receive from your bank, broker or other nominee on how to change or revoke your vote.

Attending the Special Meeting and Voting in Person

        The special meeting will be held at El Dorado's principal executive offices, 4040 El Dorado Road, Placerville, California 95667, on [            ], [2018][2019], at 10 a.m., local time. Subject to space availability, all El Dorado shareholders as of the close of business on the record date, or their duly appointed proxies, may attend the special meeting. Since seating may be limited, admission to the special meeting will be on a first-come, first-served basis. Registration and seating will begin at 9:30 a.m., local time.

        If you hold your shares of El Dorado common stock in your name as a shareholder of record and you wish to attend the special meeting and vote in person, please bring valid picture identification.

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        If your shares are held in "street name" through a broker, bank or other nominee, you may only vote in person at the El Dorado special meeting if you have proof of ownership of your shares of El Dorado common stock as of the record date and obtain a valid legal proxy from your bank, broker or other nominee that is the shareholder of record of such shares and present such items at the El Dorado special meeting. You must also bring valid picture identification.

        Any representative of a shareholder who wishes to attend the El Dorado special meeting must present acceptable documentation evidencing his or her authority, acceptable evidence of ownership by the holder of shares of El Dorado common stock and an acceptable form of identification.

Dissenters' Rights

        In connection with the merger, El Dorado shareholders will have the opportunity to exercise dissenters' rights in accordance with the procedures set forth in 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a. Copies of 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a are attached to this proxy statement/prospectus as Appendix C. A dissenting shareholder who votes "AGAINST" the merger proposal or who gives notice in writing to El Dorado at or prior to the special meeting that such holder dissents from the merger and who follows the required procedures may receive cash in an amount equal to the value of his or her shares of El Dorado common stock in lieu of the merger consideration provided for under the merger agreement. For additional details and information on how to exercise your dissenters' rights, please refer to "The Merger—Dissenters' Rights" on page 70 and Appendix C of this proxy statement/prospectus. Failure to follow all of the steps required under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a will result in the loss of your dissenters' rights.

Solicitation of Proxies

        El Dorado is soliciting proxies for the special meeting from El Dorado shareholders on behalf of its board of directors. El Dorado will bear all of the costs of the proxy solicitation for the special meeting, including the costs of preparing, printing and mailing this proxy statement/prospectus to its shareholders. In addition to solicitations by mail, El Dorado's directors, officers and employees may solicit proxies in person or by telephone, email, facsimile or other electronic methods without additional compensation. El Dorado has engaged Alliance Advisors to assist El Dorado in the solicitation of proxies and the mailing of the proxy materials for the special meeting, as well as to provide related advice and informational support. Such firm will be paid a fee of approximately $20,000 plus reimbursement of reasonable out-of-pocket expenses.

        El Dorado will reimburse brokerage firms and other custodians, nominees and fiduciaries for their reasonable out-of-pocket expenses incurred by them in forwarding proxy materials to the beneficial owners of shares of El Dorado common stock held in "street name" by such persons.

Questions and Additional Information

        If you have any questions or need assistance in voting your shares, please call George L. Cook, Chief Executive Officer of El Dorado, at (530) 622-1492.

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EL DORADO PROPOSALS

Merger Proposal

        As discussed throughout this proxy statement/prospectus, El Dorado is asking its shareholders to approve the merger proposal. Holders of shares of El Dorado common stock should read carefully this document in its entirety, including the appendices and the documents incorporated herein by reference, for more detailed information concerning the merger agreement and the merger. In particular, holders of shares of El Dorado common stock are directed to the merger agreement, a copy of which is attached as Appendix A to this proxy statement/prospectus.

        The El Dorado board of directors recommends a vote "FOR" the merger proposal.

Adjournment Proposal

        The special meeting may be adjourned to another time and place, if necessary or appropriate, to permit, among other things, the further solicitation of proxies if there are insufficient votes at the time of the special meeting to approve the merger proposal.

        If, at the special meeting, El Dorado does not have the affirmative vote of two-thirds of the outstanding shares entitled to vote to approve the merger proposal, El Dorado intends to move to adjourn the special meeting in order to enable the board of directors to solicit additional proxies for approval of the merger proposal. If the shareholders approve the adjournment proposal, El Dorado could adjourn the special meeting and use the additional time to solicit additional proxies, including the solicitation of proxies from shareholders who have previously voted.

        The El Dorado board of directors recommends a vote "FOR" the adjournment proposal.

No Other Matters

        Under Section 2.4 of El Dorado's bylaws, El Dorado may not transact any other business at the special meeting other than as listed above.

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INFORMATION ABOUT THE COMPANIES

PacWest Bancorp
9701 Wilshire Boulevard, Suite 700
Beverly Hills, California 90212
Phone: (310) 887-8500

        PacWest Bancorp, a Delaware corporation, is a bank holding company registered under the Bank Holding Company Act of 1956, as amended, referred to as the BHC Act, with corporate headquarters in Beverly Hills, California. PacWest's principal business is to serve as the holding company for PacWest's wholly-owned subsidiary, Pacific Western Bank. References to PacWest refer to PacWest together with Pacific Western Bank and its other subsidiaries on a consolidated basis.

        PacWest is focused on relationship-based business banking to small, middle-market and venture-backed businesses nationwide. It has 74 full-service, retail bank branches located throughout California, one branch located in Durham, North Carolina, and numerous loan production offices located in cities across the United States. Pacific Western Bank's Community Banking group provides lending and comprehensive deposit and treasury management services to small and medium-sized businesses conducted primarily through Pacific Western Bank's branch operations in Southern California extending from San Diego County to California's Central Coast, and four bank branches in the Central Valley. Following the merger of PacWest with CapitalSource Inc. completed on April 7, 2014, Pacific Western Bank established the National Lending group (formerly referred to as the CapitalSource Division), which provides asset-based, equipment, real estate, and security cash flow and treasury management services to established middle-market businesses on a national basis. The National Lending group's loan and lease origination efforts are conducted through key offices located in Chevy Chase, Maryland; Los Angeles and San Jose, California; St. Louis, Missouri; Denver, Colorado; Chicago, Illinois; and New York, New York. Following the merger of PacWest with Square 1 Financial, Inc. completed on October 6, 2015, Pacific Western Bank formed the Venture Banking group (formerly referred to as the Square 1 Bank Division), which offers a comprehensive suite of financial services focused on entrepreneurial businesses and their venture capital and private equity investors, with offices located in key innovation hubs across the United States. In addition, Pacific Western Bank provides investment advisory and asset management services to select clients through Square 1 Asset Management, Inc., a wholly-owned subsidiary of Pacific Western Bank and a SEC-registered investment adviser.

        Pacific Western Bank also provides special services, including international banking services, such as foreign exchange, foreign remittance, international letters of credit and foreign currency services, multi-state deposit services and cash management services, such as remote deposit capture, wire transfer and Automated Clearing House payment services, as well as product offerings through other correspondent banks. Pacific Western Bank issues ATM, debit and business credit cards, has a network of branded ATMs and offers access to ATM networks through other major service providers. Pacific Western Bank provides access to customer accounts via a 24-hour toll-free automated telephone customer service operated seven days a week and a secure online banking service.

        PacWest Bancorp was established in October 1999 and has achieved strong market positions by developing and maintaining extensive local relationships in the communities it serves. By leveraging its business model, service-driven focus, and presence in attractive markets, as well as maintaining a highly efficient operating model and robust approach to risk management, PacWest has achieved significant and profitable growth, both organically and through disciplined acquisitions. PacWest has successfully completed 29 acquisitions since 2000 which have contributed to its growth and expanded its market presence throughout the United States.

        As of September 30, 2018, PacWest had total assets of $24.8 billion, loans and leases, net of deferred fees, of $17.2 billion, total deposits of $17.9 billion, and stockholders' equity of $4.7 billion.

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        PacWest's stock is traded on NASDAQ under the symbol "PACW."

        Additional information about PacWest and its subsidiaries may be found in the documents incorporated by reference into this document. Please also see the section entitled "Where You Can Find More Information."

El Dorado Savings Bank, F.S.B.
4040 El Dorado Road
Placerville, California 95667
Phone: (530) 622-1492

        El Dorado is a federal savings association headquartered in Placerville, California. It is a member of the Federal Home Loan Bank of San Francisco and its deposits are insured by the FDIC. El Dorado provides a wide array of consumer banking products, including (i) checking, savings, money market and certificate of deposit accounts; (ii) mortgage loans, including home refinance loans, and home equity lines of credit; and (iii) mobile payment services. Since commencing operations in 1958, El Dorado has been committed to serving local residents through its branch network, which is now comprised of 31 branches in Northern California and four branches in Northern Nevada.

        As of September 30, 2018, El Dorado had total assets of approximately $2.20 billion, total deposits of approximately $1.96 billion and stockholders' equity of approximately $232 million. As of September 30, 2018, El Dorado had a Tier 1 risk-based capital ratio of 34.9%, a total risk-based capital ratio of 35.7% and a Tier 1 leverage ratio of 10.4%.

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THE MERGER

        The following is a discussion of the merger and the material terms of the merger agreement between PacWest and El Dorado. You are urged to read carefully the merger agreement in its entirety, a copy of which is attached as Appendix A to this document and incorporated by reference herein. This summary does not purport to be complete and may not contain all of the information about the merger agreement that is important to you. This section is not intended to provide you with any factual information about PacWest or El Dorado. Such information can be found elsewhere in this document and in the public filings PacWest and El Dorado make with the SEC, as described in the section entitled "Where You Can Find More Information."

Terms of the Merger

Transaction Structure

        PacWest's and El Dorado's boards of directors have approved the merger agreement and the transactions contemplated thereby. The merger agreement provides for the merger of El Dorado with and into Pacific Western Bank, a California state-chartered bank and a wholly-owned subsidiary of PacWest, with Pacific Western Bank as the surviving bank.

Merger Consideration

        In the merger, each share of El Dorado common stock owned by an El Dorado shareholder, other than certain specified excluded shares and dissenting shares described under "The Merger Agreement—Merger Consideration—Cancellation of Excluded Shares and Dissenting Shares," will be converted into the right to receive the merger consideration consisting of (i) $427.92 in cash and (ii) 58.2209 shares of PacWest common stock, subject to adjustment as set forth in the merger agreement and as further described in the sections entitled "The Merger Agreement—Merger Consideration" and "The Merger Agreement—Termination of the Merger Agreement." For each fractional share that would otherwise be issued, PacWest will pay cash in an amount equal to the fraction of a share (rounded to the nearest thousandth) of PacWest common stock which the holder would otherwise be entitled to receive multiplied by the PacWest average closing price.

        The market value of the stock portion of the merger consideration will fluctuate with the price of PacWest common stock, and the value of the shares of PacWest common stock that holders of shares of El Dorado common stock will receive upon consummation of the merger may be different than the value of the shares of PacWest common stock that holders of shares of El Dorado common stock would receive if calculated on the date PacWest and El Dorado announced the merger, on the date that this document is being mailed to El Dorado shareholders, or on the date of the special meeting of El Dorado shareholders. Based on the closing price of PacWest common stock on September 11, 2018, the value of the per share merger consideration payable to holders of shares of El Dorado common stock was $3,341.29. Based on the closing price of PacWest common stock on [            ], 2018, the last practicable date before the date of this document, the value of the per share merger consideration payable to holders of shares of El Dorado common stock was $[            ].

Background of the Merger

        The El Dorado board of directors periodically reviews, with management, its business strategies, opportunities and challenges as part of its consideration and evaluation of its long-term prospects in light of developments in its business, in the sectors in which it competes, in the economy generally and in financial markets, with the goal of enhancing value for its shareholders. Early in 2018, management of El Dorado believed that it would be prudent to reach out to an independent investment banker to discuss the financial markets and El Dorado's positioning in light of perceived future challenges for independent banks of El Dorado's size and opportunity for liquidity.

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        At the May 8, 2018 regular meeting of the El Dorado board of directors, Mr. George Cook, Jr., Chief Executive Officer of El Dorado, advised the El Dorado board of directors of recent discussions he, Mr. Meuser, Mr. Blucher and Mr. J. Cook had with a representative of Sandler in April, 2018 regarding the then current merger and acquisition market conditions and the potential value El Dorado could receive in a merger transaction. Mr. G. Cook reviewed with the El Dorado board of directors the reasons that he and the other members of executive management felt it would be a good time to explore a potential sale of El Dorado in light of the value other financial institutions were receiving in strategic transactions and the fact that a transaction would reward many of El Dorado's shareholders, or families of shareholders, who had been invested in El Dorado for as long as over 50 years. Mr. G. Cook also reviewed with the El Dorado board of directors threats from competition from lesser regulated and non-taxed credit unions, non-bank mortgage lenders and other providers of bank-like products and services. Mr. G. Cook also discussed with the El Dorado board of directors the burdens and costs of regulation, the risks associated with failing to comply with applicable regulations, cybersecurity threats and the political climate for banks generally. Mr. G. Cook also discussed with the El Dorado board of directors the business position of El Dorado, which included discussions regarding the anticipated pressure interest rate hikes would have on El Dorado's profit margin.

        In addition, Mr. G. Cook discussed with the El Dorado board of directors the potential risks associated with a sale, including the impact a failed transaction or leak of confidential information could have on El Dorado's shareholders, its employees and its customers. Following a lengthy discussion with the El Dorado board of directors and executive management regarding exploring a strategic transaction, the board of directors authorized El Dorado to enter into an engagement letter with Sandler as its exclusive financial advisor in connection with pursuing a potential strategic transaction, and the El Dorado board of directors appointed a special strategic committee comprised of directors Jack L. Cornelius, Jr., James D. Coyle III and Frederick A. Teichert, referred to as the strategic committee, to, among other things, (i) oversee management and El Dorado's financial, legal and other professional advisors in connection with, and any formal process related to, a strategic alternative and (ii) make such recommendations to the full El Dorado board of directors as the strategic committee deems appropriate, including whether, among other things, to enter into a strategic transaction.

        On May 15, 2018, El Dorado entered into the engagement letter with Sandler.

        On July 3, 2018, the strategic committee held a meeting together with a representative from Sandler, a representative from Manatt, Phelps & Phillips, LLP, counsel to El Dorado, referred to as Manatt, as well as Messrs. Blucher, G. Cook, J. Cook and Meuser. At the meeting, the Sandler representative reviewed marketing materials which Sandler and management had prepared to solicit potential interest in El Dorado from prospective third parties and discussed the anticipated timing for a merger process. The members of the strategic committee engaged in a robust dialogue with Sandler and El Dorado management regarding the positioning of El Dorado for a strategic transaction and the prospective partners which Sandler intended to contact in order to explore a strategic transaction. In addition, a representative of Manatt reviewed with the strategic committee a form of mutual confidentiality agreement that would be used with potential acquirers, including discussion of the standstill and "don't ask-don't waive" provisions contained therein which restricted each counterparty from acquiring shares of El Dorado common stock, making unsolicited acquisition proposals and from requesting El Dorado amend or waive such provisions.

        Following the presentations and discussions, the strategic committee authorized Sandler to contact a list of prospective acquirers to determine if they would be interested in signing the confidentiality agreement that the special committee reviewed with Manatt and receiving additional information about El Dorado.

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        On July 10, 2018, the El Dorado board of directors held a regular meeting. At the meeting, a representative of Manatt reviewed with the El Dorado board of directors its fiduciary duties in connection with its assessment of potential strategic transactions, including its ability to decide not to pursue a strategic transaction or reject any proposal if such proposal is not in the best interests of El Dorado and its shareholders. In addition, the representative from Manatt reviewed the potential timeline associated with a strategic transaction, including regulatory approval. Mr. G. Cook also updated the El Dorado board of directors on the strategic process, including the due diligence review being conducted by prospective strategic partners.

        Between July 3, 2018 and July 19, 2018, Sandler reached out to 24 prospective acquirers to gauge their interest in signing a mutual confidentiality agreement to explore a transaction with El Dorado. The prospective acquirers were determined based on Sandler's understanding of such prospective acquirer's financial capacity to complete a possible acquisition of El Dorado, perceived business and cultural fit and perceived potential to obtain required regulatory approvals in consultation with El Dorado management. Of those 24 parties, El Dorado executed confidentiality agreements with 10 potential transaction counterparties, all of whom were financial institutions. Six of the 10 financial institutions expressed interest in meeting with management of El Dorado and obtaining further information, and on July 5, 2018, they were provided with access to an electronic due diligence data room with non-public information regarding El Dorado. Between July 30, 2018 and August 6, 2018, El Dorado and a representative of Sandler met with each of the interested financial institutions. Following those meetings, five banks (PacWest, Party B, Party C, Party D and Party E) ultimately submitted letters of intent. The indicative values in the proposed letters of intent ranged from $349 million to $505 million, which consisted of various consideration mixes, ranging from approximately 25% cash and 75% stock to 100% cash. The various letters of intent also contained a variety of other terms, including requirements for further diligence, conditions to closing, plans for the El Dorado branch network and anticipated timing to announce and close a transaction. In addition, the consideration mix varied amongst the bidders in terms of cash and/or stock. PacWest submitted a letter of intent on August 9, 2018 for an aggregate consideration with an indicative value of approximately $456 million (based on PacWest's closing stock price as of August 8, 2018), comprised of 75% of PacWest common stock (or 47.6077 shares of PacWest common stock for each share of El Dorado common stock) and 25% of cash (or $816.47 for each share of El Dorado common stock).

        On August 8, 2018, a regular meeting of the PacWest board of directors was held. A representative from Keefe, Bruyette & Woods, Inc., referred to as KBW, who acted as PacWest's financial advisor, participated in the meeting and presented an overview of and the strategic rationale for the proposed El Dorado merger transaction. The KBW representative highlighted, among other things, El Dorado's core deposit level, El Dorado's average deposit relationship of 23 years and El Dorado's liquid balance sheet. After a discussion regarding deal pricing, deposit costs and anticipated due diligence timelines, PacWest's management noted its intention to submit a non-binding letter of intent to El Dorado.

        On August 10, 2018, Sandler preliminarily reviewed telephonically with members of El Dorado's management team the principal terms of all five letters of intent, as well as the conversations Sandler had with the potential acquirers regarding each potential acquirer's letter of intent and its underlying assumptions and concerns. In an effort to elicit each potential counterparty's best proposal and provide transparency, Sandler shared with each bidder that El Dorado's board of directors would likely choose one potential counterparty with which it would move forward exclusively.

        El Dorado management noted to Sandler on the August 10, 2018 call that, although Party B's bid was the highest nominal initial bid, the language of its letter of intent created substantial uncertainty about what its final bid price would ultimately be. In particular, El Dorado management and Sandler discussed that Party B's letter indicated that a final purchase price would be determined following satisfactory completion of Party B's due diligence and additional negotiations with El Dorado and its advisors. In addition, Party B's letter contemplated announcing a definitive agreement as late as four

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and a half months from the date of the letter, which management noted could increase the risk of damage to El Dorado's business if there were any confidentiality leaks during the long interim period. Sandler subsequently informed Party B that its bid raised a number of questions that concerned the El Dorado board of directors. These concerns included the uncertainty of Party B's final pricing, the timing of the schedule to ultimately announce a definitive agreement (by December 31, 2018), its plans for additional due diligence and the financial assumptions underlying its bid. Sandler indicated it would communicate any additional information that Party B could provide to El Dorado management and the El Dorado board of directors.

        Sandler also reached out to Party C, Party D and Party E to discuss their respective bids and acquire more background information on the terms of their proposals. Sandler communicated with each of the parties that it was unlikely there would be a second round of bidding should any party desire to increase its bid.

        In response to questions from PacWest regarding its bid, Sandler indicated that PacWest had distinguished itself as a lead potential acquirer with respect to its preparation to move forward with a transaction based on its engagement of outside experts, the level of due diligence that had been completed and its ability to timely enter into a definitive agreement and consummate a transaction, but PacWest was not the highest bidder with respect to pricing. PacWest shared detailed transaction assumptions, including assumptions informed by the engagement of its outside advisors, including KBW. Following those discussions and further interaction with representatives of PacWest and KBW, PacWest confirmed to Sandler orally on August 14, 2018 that it would be willing to increase its initial bid, which had an indicative value of approximately $456 million based on PacWest's closing stock price as of August 8, 2018 (and which was the second highest bid of the initial bids received by El Dorado) by an additional $22 million with the mix of additional consideration ultimately to be determined. In addition, in response to its August 10, 2018 conversation with Sandler, Party B provided a letter on August 13, 2018 addressing some of the questions raised by Sandler in the August 10, 2018 phone call between the parties and provided more certainty with respect to the timing of due diligence and the execution of a definitive agreement and made a specific request for additional diligence items. Party B also provided a separate form of 30-day exclusivity agreement to El Dorado but did not provide any additional definitiveness around pricing.

        On August 15, 2018, representatives of Sandler and Manatt met with the strategic committee along with Messrs. Blucher, J. Cook, G. Cook and Meuser to discuss each of the five proposals received by El Dorado. The strategic committee reviewed with Sandler, among other things: the financial terms of each of the five proposals; the aggregate value analysis of each of the five proposals over a three-year period; each prospective acquirer's business and management team; the pricing and consideration mix and impact of cash as part of the overall transaction consideration; historical stock market prices, including any increase in a bidder's stock price; prospective dividend yields and the effect of such dividends, if any, on overall value of the bids; post-transaction liquidity of stock for prospective acquirers offering stock consideration; a net present value analysis of the stock of each prospective acquirer offering stock consideration, including underlying assumptions; tax treatment of cash and stock portions of the purchase price, including the tax structuring opportunities offered by bids that included stock consideration; timing associated with entering into a definitive agreement and ultimately consummating a transaction; preparedness of each of the counterparties and level of due diligence remaining; the historical acquisition experience of each prospective acquirer; closing conditions and contingencies (including risk of pricing adjustments); corporate governance proposals for the combined enterprise; plans for any branch consolidation; and earnings per share estimates of the pro forma combined company for those offering equity. In addition, the strategic committee reviewed an analysis prepared by Sandler comparing the net present values of El Dorado in connection with a strategic transaction with a third party and as a standalone, independent entity, as well as each El Dorado

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executive officer's salary continuation agreement, which would provide each of the four executive officers with additional compensation in the event they were terminated following a change-in-control.

        After a full review of the five prospective counterparties, the strategic committee agreed to focus on the three offers that provided the highest economic value, which were from PacWest, Party B and the all-cash offer from Party D. The strategic committee noted in particular that the significantly higher dividend yield offered by PacWest, as compared to Party B, reduced the initial pricing gap with Party B. In addition, PacWest had already engaged outside consultants, including KBW, to assist with its diligence and preparedness, and the trading volume of PacWest's common stock provided substantially more liquidity than other bidders offering stock consideration. PacWest's letter also indicated that it believed it could enter into a definitive agreement with El Dorado within 21 days of acceptance of its letter and that PacWest had a history of successfully consummating a large number of acquisitions in a timely manner. In addition, the strategic committee noted that Party B had not provided any further clarity regarding determination of a final price to be offered to El Dorado's shareholders and, as a result, Party B's bid price remained uncertain. Finally, PacWest's size relative to Party B's size would result in a decreased overall execution risk of integration to El Dorado's shareholders since El Dorado would represent a smaller portion of the combined enterprise. The strategic committee also noted the pricing offered by each of the three parties and the opportunity for a transaction with PacWest or Party B, which each included equity as part of its offer, to be structured as a "reorganization" for United States federal income tax purposes.

        Following an active discussion with representatives of Sandler and Manatt, including a review of the fiduciary duties of the El Dorado board of directors, and based on the foregoing discussions and review, including, but not limited to, the certainty and confidence the PacWest bid provided, the substantially superior dividend yield offered by PacWest, PacWest's extensive experience in consummating acquisitions, the robust liquidity offered by its common stock and its demonstrated level of preparedness, the strategic committee recommended to the full El Dorado board of directors that El Dorado should enter into the non-binding letter of intent, including a 30-day exclusivity period, with PacWest subject to receiving a written, revised letter of intent clarifying the proposed $22 million increase in aggregate purchase price.

        On August 15, 2018, following the strategic committee meeting, the full El Dorado board of directors met with representatives of Sandler and Manatt to discuss the five proposals received by El Dorado and the strategic committee's conclusion that El Dorado should execute a letter of intent with PacWest. The full El Dorado board of directors also reviewed each of the items reviewed by the strategic committee during its August 15, 2018 meeting described above, including the net present value analysis of El Dorado. Following extensive discussion with Sandler and Manatt, and based on the foregoing discussions and review, including, but not limited to, the certainty and confidence the PacWest bid provided, the substantially superior dividend yield offered by PacWest, PacWest's extensive experience in consummating acquisitions, the robust liquidity offered by its common stock and PacWest's demonstrated level of preparedness, the full El Dorado board of directors authorized El Dorado to enter into the letter of intent with PacWest, including its exclusivity provisions, subject to the strategic committee's review and approval of a revised letter of intent reflecting an increase in the aggregate merger consideration of $22 million.

        After the August 15, 2018 board meeting, representatives of Sandler communicated with KBW regarding the decision of the El Dorado board of directors and indicated that the strategic committee would need to review a revised letter of intent before management of El Dorado would be authorized to execute such a letter.

        On August 16, 2018, KBW delivered a revised letter of intent to Sandler which reflected an increase from the original letter of intent of $22 million in the indicative value of the aggregate consideration (to approximately $478 million, in each case, based on PacWest's closing stock price on

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August 8, 2018, the date immediately prior to the date of the original letter of intent), but which also reflected a different overall consideration mix comprised of 90% of PacWest common stock (or 59.8721 shares of PacWest common stock for each share of El Dorado common stock) and 10% of cash (or $342.27 for each share of El Dorado common stock). Following discussions with management of El Dorado and Manatt, Sandler communicated with KBW that the substantive change in the overall mix of consideration would need to be reviewed and approved by both the strategic committee and the full El Dorado board of directors before El Dorado could execute the letter of intent.

        Furthermore, Sandler discussed directly with KBW and PacWest the change in the consideration mix and the underlying assumptions for such change and, following discussions with management of El Dorado, communicated to PacWest and KBW that an increase in the percentage of cash consideration from 10% would be important for the strategic committee and the full El Dorado board of directors.

        On August 17, 2018, KBW delivered to Sandler a revised letter of intent reflecting aggregate consideration with an indicative value of approximately $478 million, based on the PacWest closing price on August 8, 2018, the date of the original letter of intent, comprised of 87.5% of PacWest common stock (or 58.2209 shares of PacWest common stock for each share of El Dorado common stock) and 12.5% of cash (or $427.92 for each share of El Dorado common stock).

        On August 20, 2018, at a joint meeting of the strategic committee and the El Dorado board of directors, the directors reviewed with representatives of Sandler and Manatt the revised proposal from PacWest together with additional materials Sandler had prepared comparing PacWest's latest proposal along with those of Party B and Party D. The strategic committee and the El Dorado board of directors had determined that the proposals from Party C and Party E were insufficient to move forward with an exclusive arrangement. The directors reviewed with Sandler the impact of the revised consideration mix proposed by PacWest on the overall value to be received by El Dorado's shareholders together with, among other things, pro forma financial projections reflecting the impact of the addition of El Dorado on a combined institution to PacWest and Party B and the issuance of stock consideration as part of the merger consideration by both PacWest and Party B. Sandler also reviewed the transaction value of each of PacWest, Party B and Party D, with Party D's all cash bid being approximately 9% less than the indicative value of the revised PacWest bid.

        In addition, Sandler reviewed an aggregate historical pricing analysis over the last three years for each of PacWest, Party B and Party D, along with additional assumptions used by PacWest in arriving at the overall mix and value of consideration in its latest offer. The aggregate historical pricing analysis provided a longer term view of the value of the consideration being offered by each of PacWest, Party B and Party D inclusive of cash consideration and the historical trading prices of the common stock of PacWest and Party B (the two institutions offering stock consideration) over a shorter period of time so that the El Dorado board of directors could better understand the value of such stock consideration. Sandler also discussed the publicly available analyst estimates for each of PacWest and Party B, including the mean and median recommendations of analysts and earnings per share estimates for fiscal year 2018 and 2019, with PacWest noted to have a median and mean recommendation of "Buy" and Party B of "Hold." The El Dorado board of directors discussed the benefits of a transaction with PacWest to El Dorado shareholders who wished to hold PacWest common stock, including PacWest's dividend yield (which substantially exceeded the dividend yield of Party B), the liquidity availability for those shareholders who wished to liquidate their ownership in PacWest after the consummation of the transaction (which substantially exceeded the liquidity of Party B), the consideration mix, as well as the effects of the merger on the combined institution, including the execution risk of integration with a smaller institution such as Party B. Members of El Dorado management presented their opinions to the strategic committee and the full El Dorado board of directors as to why they believed PacWest represented the best offer for El Dorado's shareholders, including based on the input they received from the due diligence meetings they held with the management team of each of the various bidders. Following the discussion, the strategic committee

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unanimously recommended that the full El Dorado board of directors accept the letter of intent from PacWest. Following approval of the strategic committee's recommendation by the full El Dorado board of directors, El Dorado countersigned the letter of intent on August 20, 2018.

        Between August 20, 2018 and September 10, 2018, PacWest performed its continuing due diligence of El Dorado, including through in-person meetings with members of El Dorado's management on August 28th and 29th, 2018, on-site loan review between August 31, 2018 and September 5, 2018 and review of materials in El Dorado's electronic due diligence data room.

        On August 31, 2018, PacWest and its counsel, Sullivan & Cromwell, LLP, referred to as S&C, delivered the first draft of the merger agreement to Manatt, and on September 4, 2018, PacWest and S&C delivered the first drafts of the related forms of voting agreements, non-solicitation agreements, non-solicitation and non-competition agreements to Manatt. Finally, on September 6, PacWest and S&C delivered the first drafts of the consulting agreements to be entered into by PacWest with Mr. Meuser, Mr. Blucher and Mr. G. Cook.

        In addition, El Dorado conducted reverse due diligence on PacWest, including a conference call with PacWest management on September 5, 2018 to review, among other things, PacWest's financial position and forecast, expectations regarding long-term growth and strategic planning and the impact the consummation of the acquisition of El Dorado would have on a combined franchise.

        On September 6, 2018, the strategic committee held a meeting with El Dorado management and representatives of Sandler and Manatt to review the initial draft of the merger agreement and proposed comments thereon. The strategic committee actively discussed with management and Manatt the terms of the merger agreement and negotiating positions as to PacWest.

        Between September 6, 2018 and September 10, 2018, representatives of El Dorado and PacWest and their respective legal counsel and financial advisors, conducted negotiations regarding the terms of the merger agreement, including, among other terms, the scope of the representations, warranties, covenants and closing conditions, including with respect to required balances of certain El Dorado deposits at closing, compensation and benefits for continuing employees following the merger, and adjustments to the merger consideration relating to certain potential title defects and/or environmental conditions with respect to El Dorado's real property. In addition, the terms of voting, non-solicitation, non-solicitation and non-competition and consulting agreements between PacWest and the individual directors of El Dorado and certain executive officers of El Dorado were negotiated. In addition, additional due diligence was conducted between the parties.

        On September 11, 2018, the strategic committee and the El Dorado board of directors held a joint meeting. At the September 11, 2018, meeting representatives of Sandler delivered its oral opinion, which was subsequently confirmed in writing, to the effect that, as of such date, the merger consideration set forth in the merger agreement was fair, from a financial point of view, to the holders of El Dorado common stock. Following extensive review and discussion by the strategic committee and the El Dorado board of directors with representatives of Manatt of the merger agreement, a copy of which had been distributed to the El Dorado directors prior to the meeting, and the related voting agreements, non-solicitation agreements, non-solicitation and non-competition agreements and consulting agreements to be entered into in connection therewith, copies of which had been made available to the El Dorado directors in advance of the meeting, the El Dorado strategic committee recommended to the full El Dorado board of directors approval of the merger agreement and the transactions contemplated thereby. Following the strategic committee's recommendation and extensive discussion, taking into account the factors described below under "—Recommendation of the El Dorado Board of Directors and Reasons for the Merger", El Dorado's full board of directors approved the merger agreement and the merger.

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        On September 11, 2018, a joint special meeting of the PacWest and Pacific Western Bank board of directors was also held. PacWest management and representatives of KBW and S&C participated. KBW and S&C summarized the negotiations that had taken place and reviewed the merger consideration to be paid by PacWest. S&C outlined for the PacWest directors the terms of the merger agreement, a copy and summary of which had been distributed to the PacWest directors prior to the meeting, and the related voting agreements, non-solicitation agreements, non-solicitation and non-competition agreements and consulting agreements to be entered into in connection therewith, copies of which had been made available to the PacWest directors in advance of the meeting. S&C then reviewed with the PacWest board of directors the PacWest directors' fiduciary duties under applicable law. The PacWest board of directors then engaged in a vigorous discussion of the terms of the agreements, the representatives of S&C and KBW answered the PacWest directors' various questions and PacWest management reviewed its due diligence findings. After extensive discussion and taking into account the factors described below under "—PacWest's Reasons for the Merger", the PacWest board of directors adopted resolutions approving the merger agreement and transactions contemplated thereby.

        Following the El Dorado and PacWest boards of directors meetings, the terms of the merger agreement and related agreements were finalized, and the agreements were executed and delivered. The transaction was publicly announced on the morning of September 12, 2018, in a press release issued by PacWest. Based on a $50.04 per share closing price of PacWest common stock on September 11, 2018, the indicative value of the aggregate merger consideration was approximately $466.7 million, or $3,341.29 per share of El Dorado common stock.

Recommendation of the El Dorado Board of Directors and Reasons for the Merger

        The El Dorado board of directors has determined that the merger is fair to and in the best interests of El Dorado and its shareholders and, by the unanimous vote of all of the directors of El Dorado, approved and adopted the merger agreement and the merger. ACCORDINGLY, THE EL DORADO BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT ALL HOLDERS OF EL DORADO COMMON STOCK VOTE "FOR" THE MERGER PROPOSAL.

        In reaching its decision to approve the merger agreement and the transactions contemplated thereby, the El Dorado board of directors evaluated the merger agreement in consultation with El Dorado's executive management and determined that the merger was the best option reasonably available for its shareholders in the current challenging and uncertain banking market. The El Dorado board of directors also consulted with its legal counsel regarding its fiduciary duties, the terms of the merger agreement and related issues and reviewed with its financial advisors and its executive management the financial aspects of the proposed transaction, considerations of the broader financial market and the fairness of the transaction to the shareholders from a financial point of view, among other matters.

        In reaching its determination to approve the merger agreement, the El Dorado board of directors considered all factors it deemed material. The El Dorado board of directors analyzed information with respect to the financial condition, results of operations, business and prospects of El Dorado. In this regard, the El Dorado board of directors considered the performance trends of El Dorado over the past several years and prospects for future growth. The board also considered El Dorado's ability to further enhance shareholder value without engaging in a strategic transaction as well as the short-term and long-term interests of El Dorado and its shareholders, including whether those interests might best be served by continued independence.

        In reaching its decision to approve the merger agreement and the merger, the El Dorado board of directors also considered a number of factors, including the following:

•

information with respect to El Dorado's and PacWest's business, earnings, operations, financial condition and prospects;

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•

the synergies unique to a transaction between El Dorado and PacWest, taking into account the results of El Dorado's due diligence review of PacWest and information provided by PacWest's management, including, but not limited to, the retention of all of El Dorado's branches following consummation of the merger;



•

the terms offered and discussions held with other prospective strategic partners;



•

El Dorado's knowledge of the national, regional and local economic conditions in the current environment in the financial services industry, including the interest rate environment, political environment and environment for community banks, particularly in California;



•

the uncertainties in the regulatory climate for financial institutions, increased operating costs resulting from compliance requirements, compliance risks and threats posed by cybersecurity incidents;



•

the financial and growth prospects for El Dorado and its shareholders in a business combination with PacWest as compared to continuing to operate as a stand-alone entity;



•

the greater market capitalization and trading liquidity of PacWest common stock in the event that El Dorado shareholders desire to sell the shares of PacWest common stock to be received by them following completion of the merger;



•

the stock component of the merger consideration in the transaction will allow El Dorado's shareholders to continue to participate in the future success of PacWest and derive the benefits from PacWest's dividends, with such dividends having a significantly higher dividend yield, as compared to other bidders, any achieved synergies of any future transactions that might be pursued by PacWest, as well as the cash component of the merger consideration, which will allow El Dorado's shareholders to receive some immediate fixed consideration;



•

PacWest's successful track record with respect to the integration of acquisitions;



•

the benefits to El Dorado's employees and its customers of operating as part of a larger organization, including with respect to product diversification, services and financial resources;



•

the low overall execution risk of integration with PacWest, since El Dorado would represent a smaller portion of the combined enterprise as compared to other bidders and the retention of all of El Dorado's branches;



•

its assessment of the likelihood that PacWest had the ability to enter into a definitive agreement and consummate the merger in a timely manner, including the likelihood that the merger will receive all necessary regulatory approvals in a timely manner;



•

the results of discussions with third parties that the El Dorado board of directors believed, in consultation with Sandler, its financial advisor, were the parties likely to have the strategic interest and financial capability to pursue a potential strategic transaction with El Dorado;



•

the financial analyses presented by representatives of Sandler to the El Dorado board of directors with respect to PacWest and the merger, and the opinion of Sandler to the effect that, as of the date of that opinion and subject to the qualifications and assumptions set forth in the opinion, the merger consideration was fair to the holders of shares of El Dorado common stock from a financial point of view (see "The Merger—Opinion of El Dorado's Financial Advisor");



•

the belief of the El Dorado board of directors that the merger consideration exceeds El Dorado's likely value in the absence of a merger, including its potential for future growth, which belief was based on a number of factors, including:



•

the risks and uncertainties associated with maintaining El Dorado's performance as a stand-alone company;

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•

the El Dorado board of directors' analysis of other strategic alternatives available to El Dorado;



•

the expectation that the merger will qualify as a "reorganization" for United States federal income tax purposes; and



•

the terms of the merger agreement, including the fixed exchange ratio, the form of merger consideration and the inclusion of a cash component, the expected tax treatment, the achievability of the closing conditions and the deal protection and termination fee provisions, which the El Dorado board of directors reviewed with its outside legal and financial advisors, which terms are described more fully under the section entitled "The Merger Agreement."

        In the course of its deliberations regarding the merger, the El Dorado board of directors also considered potential risks and potentially negative factors associated with the merger, including the following material factors:

•

the need to obtain approval from two-thirds of the outstanding shares of El Dorado common stock, as well as regulatory approvals, in order to complete the transaction and the risk that those or other closing conditions will not be satisfied;



•

the fact that the value of the aggregate and per share merger consideration will fluctuate with the market price of PacWest's common stock and the risk that PacWest's common stock price might decline, reducing the aggregate and per share merger consideration from the values at the time the merger agreement was approved;



•

the potential risk of diverting management focus and resources from other strategic opportunities and from operational matters while working to implement the merger;



•

the potential negative effects on El Dorado's business and customer relationships as a result of the pending merger;



•

the merger-related costs;



•

the fact that certain employee-directors and executive officers of El Dorado have interests in the merger and have arrangements that are different from or in addition to those of El Dorado shareholders generally; and



•

the fact that El Dorado would be prohibited from affirmatively soliciting acquisition proposals after execution of the merger agreement and will be obligated to pay a termination fee of $18.6 million to PacWest if the merger agreement is terminated under certain circumstances, all of which may discourage other parties potentially interested in a strategic transaction with El Dorado from pursuing such a transaction.

        This description of the information and factors considered by the El Dorado board of directors is not intended to be exhaustive, but is believed to include all material factors the El Dorado board of directors considered. In determining whether to approve and recommend the merger agreement, the El Dorado board of directors did not assign any relative or specific weights to any of the foregoing factors and individual directors may have weighed factors differently. After deliberating with respect to the merger and the merger agreement, considering, among other things, the reasons discussed above, the El Dorado board of directors approved the merger agreement and the merger as being in the best interests of El Dorado and its shareholders, based on the total mix of information then available to the El Dorado board of directors.

Opinion of El Dorado's Financial Advisor

        El Dorado retained Sandler to act as financial advisor to El Dorado's board of directors in connection with El Dorado's consideration of a possible business combination. El Dorado selected Sandler as its financial advisor because Sandler is a nationally recognized investment banking firm whose principal business specialty is financial institutions. In the ordinary course of its investment banking business, Sandler is regularly engaged in the valuation of financial institutions and their securities in connection with mergers and acquisitions and other corporate transactions.

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        Sandler acted as financial advisor to El Dorado in connection with the proposed merger and participated in certain of the negotiations leading to the execution of the merger agreement. At the September 11, 2018 meeting at which El Dorado's board of directors considered the merger agreement, Sandler delivered to the board its oral opinion, which was subsequently confirmed in writing, to the effect that, as of such date, the merger consideration was fair to the holders of El Dorado common stock from a financial point of view. The full text of Sandler's opinion is attached as Appendix D to this proxy statement/prospectus. The opinion outlines the procedures followed, assumptions made, matters considered and qualifications and limitations on the review undertaken by Sandler in rendering its opinion. The description of the opinion set forth below is qualified in its entirety by reference to the full text of the opinion. Holders of shares of El Dorado common stock are urged to read the entire opinion carefully in connection with their consideration of the proposed merger.

        Sandler's opinion speaks only as of the date of the opinion. The opinion was directed to El Dorado's board of directors in connection with its consideration of the merger agreement and the merger and does not constitute a recommendation to any shareholder of El Dorado as to how such shareholder should vote at any meeting of shareholders called to consider and vote upon the approval of the merger. Sandler's opinion was directed only to the fairness, from a financial point of view, of the merger consideration to the holders of shares of El Dorado common stock and did not address the underlying business decision of El Dorado to engage in the merger, the form or structure of the merger or any other transactions contemplated in the merger agreement, the relative merits of the merger as compared to any other alternative transactions or business strategies that might exist for El Dorado or the effect of any other transaction in which El Dorado might engage. Sandler also did not express any opinion as to the amount or nature of the compensation to be received in the merger by any officer, director or employee of El Dorado or PacWest, or any class of such persons, if any, relative to the compensation to be received by any other shareholder. Sandler's opinion was approved by Sandler's fairness opinion committee.

        In connection with its opinion, Sandler reviewed and considered, among other things:

•

a draft of the merger agreement, dated September 10, 2018;



•

certain financial statements and other historical financial information of El Dorado that Sandler deemed relevant;



•

certain publicly available financial statements and other historical financial information of PacWest that Sandler deemed relevant;



•

certain internal financial projections for El Dorado for the years ending December 31, 2018 through December 31, 2022, as provided by the senior management of El Dorado;



•

publicly available mean analyst net income estimates for PacWest for the years ending December 31, 2018 and December 31, 2019, a diluted number of common shares of PacWest outstanding for the second quarter of 2018, as well as estimated long-term net income and asset growth rates for the years after 2019 and estimated dividends per share for the years ending December 31, 2018 through December 31, 2022, that were discussed with Sandler by PacWest management and used and relied on based on such discussions;



•

the pro forma financial impact of the merger on PacWest based on certain assumptions relating to transaction expenses, purchase accounting adjustments, cost savings and revenue reductions, following the closing of the merger and certain balance sheet restructuring transactions, as well as net income projections for El Dorado for the years ending December 31, 2018 through December 31, 2022, as adjusted by the senior management of PacWest, as provided by the senior management of PacWest, which are collectively referred to as the Pro Forma Assumptions;

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•

the publicly reported historical price and trading activity for PacWest common stock, including a comparison of certain stock market information for PacWest common stock and certain stock indices as well as publicly available information for certain other similar companies, the securities of which are publicly traded;



•

a comparison of certain financial information for El Dorado and PacWest with similar financial institutions for which information is publicly available;



•

the financial terms of certain recent business combinations in the bank and thrift industry (on a nationwide basis), to the extent publicly available;



•

the current market environment generally and the banking environment in particular; and



•

such other information, financial studies, analyses and investigations and financial, economic and market criteria as Sandler considered relevant.

        Sandler also discussed with certain members of the senior management of El Dorado the business, financial condition, results of operations and prospects of El Dorado and held similar discussions with certain members of the senior management of PacWest and its representatives regarding the business, financial condition, results of operations and prospects of PacWest.

        In performing its review, Sandler relied upon the accuracy and completeness of all of the financial and other information that was available to and reviewed by Sandler from public sources, that was provided to Sandler by El Dorado or PacWest or their respective representatives or that was otherwise reviewed by Sandler, and Sandler assumed such accuracy and completeness for purposes of rendering its opinion without any independent verification or investigation. Sandler relied on the assurances of the respective managements of El Dorado and PacWest that they were not aware of any facts or circumstances that would make any of such information inaccurate or misleading. Sandler was not asked to undertake, and did not undertake, an independent verification of any of such information and Sandler did not assume any responsibility or liability for the accuracy or completeness thereof. Sandler did not make an independent evaluation or perform an appraisal of the specific assets, the collateral securing assets or the liabilities (contingent or otherwise) of El Dorado or PacWest or any of their respective subsidiaries, nor was Sandler furnished with any such evaluations or appraisals. Sandler rendered no opinion or evaluation on the collectability of any assets or the future performance of any loans of El Dorado or PacWest. Sandler did not make an independent evaluation of the adequacy of the allowance for loan losses of El Dorado or PacWest, or the combined entity after the merger, and Sandler did not review any individual credit files relating to El Dorado or PacWest. Sandler assumed, with El Dorado's consent, that the respective allowances for loan losses for both El Dorado and PacWest were adequate to cover such losses and would be adequate on a pro forma basis for the combined entity.

        In preparing its analyses, Sandler used certain internal financial projections for El Dorado for the years ending December 31, 2018 through December 31, 2022, as provided by the senior management of El Dorado. In addition, Sandler used publicly available mean analyst net income estimates for PacWest for the years ending December 31, 2018 and December 31, 2019, a diluted number of common shares of PacWest Bancorp outstanding for the second quarter of 2018, as well as estimated long-term net income and asset growth rates for the years after 2019 and estimated dividends per share for the years ending December 31, 2018 through December 31, 2022, that were discussed with Sandler by PacWest management and used and relied on based on such discussions. Sandler also received and used in its pro forma analyses the Pro Forma Assumptions, as provided by the senior management of PacWest. With respect to the foregoing information, the respective senior managements of El Dorado and PacWest confirmed to Sandler that such information reflected (or, in the case of the publicly available mean analyst estimates referred to above, were consistent with) the best currently available projections, estimates and judgments of those respective senior managements as to the future financial performance

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of El Dorado and PacWest, respectively, and the other matters covered thereby, but was based on numerous variables and assumptions that are inherently uncertain, including, without limitation, factors related to general economic and competitive conditions and that, accordingly, actual results could vary significantly from those set forth in such information. However, Sandler assumed that the future financial performance reflected in such information would be achieved. Sandler expressed no opinion as to such information, or the assumptions on which such information was based. Sandler also assumed that there had been no material change in the respective assets, financial condition, results of operations, business or prospects of El Dorado or PacWest since the date of the most recent financial statements made available to Sandler. Sandler assumed in all respects material to Sandler's analysis that El Dorado and PacWest would remain as going concerns for all periods relevant to Sandler's analysis.

        Sandler also assumed, with El Dorado's consent, that (i) each of the parties to the merger agreement would comply in all material respects with all material terms and conditions of the merger agreement and all related agreements, that all of the representations and warranties contained in such agreements were true and correct in all material respects, that each of the parties to such agreements would perform in all material respects all of the covenants and other obligations required to be performed by such party under such agreements and that the conditions precedent in such agreements were not and would not be waived, (ii) in the course of obtaining the necessary regulatory or third party approvals, consents and releases with respect to the merger, no delay, limitation, restriction or condition would be imposed that would have an adverse effect on El Dorado, PacWest or the merger or any related transactions and (iii) the merger and any related transactions would be consummated in accordance with the terms of the merger agreement without any waiver, modification or amendment of any material term, condition or agreement thereof and in compliance with all applicable laws and other requirements. Finally, with El Dorado's consent, Sandler relied upon the advice that El Dorado received from its legal, accounting and tax advisors as to all legal, accounting and tax matters relating to the merger and the other transactions contemplated by the merger agreement. Sandler expressed no opinion as to any such matters.

        Sandler's opinion was necessarily based on financial, regulatory, economic, market and other conditions as in effect on, and the information made available to Sandler as of the date thereof. Events occurring after the date thereof could materially affect Sandler's opinion. Sandler has not undertaken to update, revise, reaffirm or withdraw its opinion or otherwise comment upon events occurring after the date thereof. Sandler expressed no opinion as to the trading value of PacWest common stock at any time or what the value of PacWest common stock would be once it is actually received by the holders of El Dorado common stock.

        In rendering its opinion, Sandler performed a variety of financial analyses. The summary below is not a complete description of all the analyses underlying Sandler's opinion or the presentation made by Sandler to El Dorado's board of directors, but is a summary of the material analyses performed and presented by Sandler. The summary includes information presented in tabular format. In order to fully understand the financial analyses, these tables must be read together with the accompanying text. The tables alone do not constitute a complete description of the financial analyses. The preparation of a fairness opinion is a complex process involving subjective judgments as to the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances. The process, therefore, is not necessarily susceptible to a partial analysis or summary description. Sandler believes that its analyses must be considered as a whole and that selecting portions of the factors and analyses to be considered without considering all factors and analyses, or attempting to ascribe relative weights to some or all such factors and analyses, could create an incomplete view of the evaluation process underlying its opinion. Also, no company included in Sandler's comparative analyses described below is identical to El Dorado or PacWest and no transaction is identical to the merger. Accordingly, an analysis of comparable companies or transactions involves complex

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considerations and judgments concerning differences in financial and operating characteristics of the companies and other factors that could affect the public trading values or merger transaction values, as the case may be, of El Dorado and PacWest and the companies to which they were compared. In arriving at its opinion, Sandler did not attribute any particular weight to any analysis or factor that it considered. Rather, Sandler made qualitative judgments as to the significance and relevance of each analysis and factor. Sandler did not form an opinion as to whether any individual analysis or factor (positive or negative) considered in isolation supported or failed to support its opinion, rather, Sandler made its determination as to the fairness of the per share merger consideration to the holders of shares of El Dorado common stock on the basis of its experience and professional judgment after considering the results of all its analyses taken as a whole.

        In performing its analyses, Sandler also made numerous assumptions with respect to industry performance, business and economic conditions and various other matters, many of which cannot be predicted and are beyond the control of El Dorado, PacWest, and Sandler. The analyses performed by Sandler are not necessarily indicative of actual values or future results, both of which may be significantly more or less favorable than suggested by such analyses. Sandler prepared its analyses solely for purposes of rendering its opinion and provided such analyses to El Dorado's board of directors at its September 11, 2018 meeting. Estimates on the values of companies do not purport to be appraisals or necessarily reflect the prices at which companies or their securities may actually be sold. Such estimates are inherently subject to uncertainty and actual values may be materially different. Accordingly, Sandler's analyses do not necessarily reflect the value of El Dorado common stock or PacWest common stock or the prices at which El Dorado or PacWest common stock may be sold at any time. The analyses of Sandler and its opinion were among a number of factors taken into consideration by El Dorado's board of directors in making its determination to approve the merger agreement and the analyses described below should not be viewed as determinative of the decision of El Dorado's board of directors with respect to the fairness of the merger.

        Summary of Implied Transaction Value and Implied Transaction Metrics.    Sandler reviewed the financial terms of the proposed transaction. Sandler calculated an implied purchase price per share of $3,342.46, or an aggregate implied transaction value of approximately $466.9 million, consisting of the sum of (i) the implied value of 58.2209 shares of PacWest common stock based on the closing price of PacWest common stock on September 10, 2018, plus (ii) $427.92. Based upon financial information for El Dorado as of or for the most recent available completed quarter, referred to as the MRQ, ended June 30, 2018, and internal financial projections for El Dorado for the year ending December 31, 2018, as provided by the senior management of El Dorado, Sandler calculated the following implied transaction metrics:

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El Dorado Comparable Company Analysis.

        Sandler used publicly available information as of June 30, 2018, unless otherwise noted, to compare selected financial information for El Dorado with a group of financial institutions selected by Sandler, referred to as the El Dorado Peer Group. The El Dorado Peer Group included 19 banks and thrifts headquartered in the Western region of the United States with securities that are publicly traded on major United States exchanges and assets between $1.0 billion and $5.0 billion, but excluded targets of announced merger transactions. The El Dorado Peer Group consisted of the following companies:

        Unless otherwise indicated in the table below, the analysis compared publicly available financial information as of or for the period ended June 30, 2018 for El Dorado with corresponding publicly available data for the El Dorado Peer Group as of or for the period ended June 30, 2018, with pricing data as of September 10, 2018. The table below sets forth the data for El Dorado and the high, low, mean, and median data for the El Dorado Peer Group. Certain financial data prepared by Sandler, as referenced in the table presented below, may not correspond to the data presented in El Dorado's historical financial statements, as a result of the different periods, assumptions and methods used by Sander to compute the financial data presented.

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        El Dorado Net Present Value Analysis.    Sandler performed an analysis that estimated the net present value per share of El Dorado common stock, assuming El Dorado performed in accordance with internal financial projections for El Dorado for the years ending December 31, 2018 through December 31, 2022, as provided by the management of El Dorado. To approximate the terminal value of a share of El Dorado common stock at December 31, 2022, Sandler applied price to 2022 earnings multiples ranging from 12.5x to 20.0x and multiples of December 31, 2022 tangible book value ranging from 120% to 220%. The terminal values were then discounted to present values using different discount rates ranging from 10.0% to 15.0%, which were chosen to reflect different assumptions regarding required rates of return of holders or prospective buyers of El Dorado common stock. As illustrated in the following tables, the analysis indicated an imputed range of values per share of El Dorado common stock of $1,147.22 to $2,190.19 when applying multiples of earnings and $1,495.27 to $3,279.13 when applying multiples of tangible book value.

 

        Sandler also considered and discussed with the El Dorado board of directors how this analysis would be affected by changes in the underlying assumptions, including variations with respect to earnings. To illustrate this impact, Sandler performed a similar analysis, assuming El Dorado's earnings varied from 15% above projections to 15% below projections. This analysis resulted in the following range of per share values for El Dorado common stock, applying the price to 2022 earnings multiples range of 12.5x to 20.0x referred to above and a discount rate of 12.68%.

        Sandler noted that the net present value analysis is a widely used valuation methodology, but the results of such methodology are highly dependent upon the numerous assumptions that must be made, and the results thereof are not necessarily indicative of actual values or future results.

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        Analysis of Precedent Transactions.    Sandler reviewed a group of merger and acquisition transactions consisting of U.S. bank and thrift transactions announced between January 1, 2018 and September 10, 2018 with target company assets between $1.0 billion and $3.0 billion and reported deal values, referred to as the Precedent Transactions.

        The Precedent Transactions group was composed of the following transactions:

        Using the latest publicly available information prior to the announcement of the relevant transaction, Sandler reviewed the following transaction metrics: transaction price to last-twelve-months earnings per share, transaction price to estimated earnings per share (in the case of the two transactions in which publicly available mean analyst estimates for the target company were then publicly available), transaction price to book value per share, transaction price to tangible book value per share and core deposit premium. Sandler compared the indicated transaction metrics for the merger to the high, low, mean and median metrics of the Precedent Transactions.

        PacWest Comparable Company Analysis.    Sandler used publicly available information as of June 30, 2018, unless otherwise noted, to compare selected financial information for PacWest with a group of financial institutions selected by Sandler, referred to as the PacWest Peer Group. The PacWest Peer Group included 15 United States-based banks with securities that are publicly traded on major United

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States exchanges and assets between $20.0 billion and $30.0 billion, but excluded targets of announced merger transactions. The PacWest Peer Group consisted of the following companies:

        Unless otherwise indicated in the table below, the analysis compared publicly available financial information as of or for the period ended June 30, 2018 for PacWest with corresponding publicly available data for the PacWest Peer Group as of or for the period ended June 30, 2018, with pricing data as of September 10, 2018. The table below sets forth the data for PacWest and the high, low, mean and median data for PacWest Peer Group. Certain financial data prepared by Sandler, as referenced in the table presented below, may not correspond to the data presented in PacWest's historical financial statements, as a result of the different periods, assumptions and methods used by Sander to compute the financial data presented.

        PacWest Stock Trading History.    Sandler reviewed the historical publicly reported trading price of PacWest common stock for the one-year and three-year periods ended September 10, 2018. Sandler then compared the relationship between the movements in the price of PacWest common stock to movements in the PacWest Peer Group as well as certain stock indices.

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PacWest One-Year Stock Performance

PacWest Three-Year Stock Performance

        PacWest Net Present Value Analysis.    Sandler performed an analysis that estimated the net present value per share of PacWest common stock, assuming that PacWest performed in accordance with publicly available mean analyst net income estimates for PacWest for the years ending December 31, 2018 and December 31, 2019 and estimated long-term net income and asset growth rates for the years after 2019, that were discussed with Sandler by PacWest management and used and relied on based on such discussions. This analysis utilized a diluted number of common shares of PacWest outstanding for the second quarter of 2018 and dividends per share estimates for the years ending December 31, 2018 through December 31, 2022, as provided by the senior management of PacWest. To approximate the terminal value of a share of PacWest common stock at December 31, 2022, Sandler applied price to 2022 earnings multiples ranging from 13.0x to 18.0x and multiples of December 31, 2022 tangible book value ranging from 195% to 295%. The terminal values were then discounted to present values using different discount rates ranging from 8.0% to 13.0%, which were chosen to reflect different assumptions regarding required rates of return of holders or prospective buyers of PacWest common stock. As illustrated in the following tables, the analysis indicated an imputed range of values per share of PacWest common stock of $45.90 to $72.69 when applying multiples of earnings and $38.80 to $65.34 when applying multiples of tangible book value.

 

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        Sandler also considered and discussed with the El Dorado board of directors how this analysis would be affected by changes in the underlying assumptions, including variations with respect to earnings. To illustrate this impact, Sandler performed a similar analysis assuming PacWest's earnings varied from 15% above estimates to 15% below estimates. This analysis resulted in the following range of per share values for PacWest common stock, applying the price to 2022 earnings multiples range of 13.0x to 18.0x referred to above and a discount rate of 10.79%.

        Sandler noted that the net present value analysis is a widely used valuation methodology, but the results of such methodology are highly dependent upon the numerous assumptions that must be made, and the results thereof are not necessarily indicative of actual values or future results.

        Pro Forma Merger Analysis.    Sandler analyzed certain potential pro forma effects of the merger, assuming the merger closes at the end of the first calendar quarter of 2019. Sandler utilized the following information and assumptions: (i) publicly available mean analyst net income estimates for PacWest for the years ending December 31, 2018 and December 31, 2019, a diluted number of common shares of PacWest outstanding for the second quarter of 2018, as well as estimated long-term net income and asset growth rates for the years after 2019 and estimated dividends per share for the years ending December 31, 2018 through December 31, 2022, that were discussed with Sandler by PacWest management and used and relied on based on such discussions, (ii) net income projections for El Dorado for the years ending December 31, 2018 through December 31, 2022, as adjusted by the senior management of PacWest, as provided by the senior management of PacWest, and (iii) certain assumptions relating to transaction expenses, purchase accounting adjustments, cost savings and revenue reductions, following the closing of the merger and certain balance sheet restructuring transactions, as provided by the senior management of PacWest. The analysis indicated that the merger could be dilutive to PacWest's estimated earnings per share (excluding one-time transaction expenses) in the years ending December 31, 2019, accretive to PacWest's estimated earnings per share (excluding one-time transaction expenses) for each of the years ending December 31, 2020 through December 31, 2022, dilutive to PacWest's estimated tangible book value per share at close and at December 31, 2019 and December 31, 2020, and accretive to PacWest's estimated tangible book value per share at December 31, 2021 and December 31, 2022.

        In connection with this analysis, Sandler considered and discussed with the El Dorado board of directors how the analysis would be affected by changes in the underlying assumptions, including the impact of final purchase accounting adjustments determined at the closing of the merger, and noted that the actual results achieved by the combined company may vary from projected results and the variations may be material.

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        Sandler's Relationship.    Sandler is acting as El Dorado's financial advisor in connection with the merger and will receive a fee for such services in an amount equal to 1.41% of the aggregate purchase price, which fee at the time of announcement of the merger was estimated to be approximately $6.6 million. Sandler's fee is contingent upon the closing of the merger. Sandler will also receive a fee from El Dorado for rendering its opinion, which opinion fee will be credited in full towards the transaction fee becoming payable to Sandler at the closing of the merger. El Dorado has also agreed to indemnify Sandler against certain claims and liabilities arising out of Sandler's engagement and to reimburse Sandler for certain of its out-of-pocket expenses incurred in connection with Sandler's engagement. Sandler did not provide any other investment banking services to El Dorado in the two years preceding the date of Sandler's opinion. In the two years preceding the date of Sandler's opinion, Sandler provided certain investment banking services to PacWest and received fees for such services estimated to be approximately equal to $3,500,000. Most recently, Sandler acted as financial advisor to PacWest and rendered a fairness opinion in connection with PacWest's acquisition of CU Bancorp, which transaction closed in October 2017. In addition, an affiliate of Sandler, Sandler O'Neill Mortgage Finance L.P., has provided certain services to PacWest in the two years preceding the date of Sandler's opinion in connection with the PacWest's sale of loans and has received fees for such services estimated to be approximately equal to $3,300,000. Sandler has advised the El Dorado board of directors that it may provide, and receive compensation for, investment banking services to PacWest in the future, including during the pendency of the merger. In the ordinary course of Sandler's business as a broker-dealer, Sandler may purchase securities from and sell securities to El Dorado, PacWest and their respective affiliates. Sandler may also actively trade the equity and debt securities of PacWest and its affiliates for Sandler's own accounts and for the accounts of Sandler's customers.

PacWest's Reasons for the Merger

        In reaching its decision to approve the merger agreement, the merger and the other transactions contemplated by the merger agreement, the PacWest board of directors consulted with PacWest senior management, as well as its financial and legal advisors, and considered a number of factors, including the following material factors:

•

each of PacWest's, El Dorado's and the combined company's business, operations, financial condition, asset quality, earnings and prospects;



•

the potential to grow core deposits and the improvement in PacWest's deposit and liquidity position by adding El Dorado's strong deposit franchise and liquid balance sheet;



•

the opportunity to grow PacWest's presence in Northern California and Northern Nevada and complement PacWest's existing franchise by adding El Dorado's mortgage-lending and community banking business, as well as the opportunity to provide expanded access to commercial lending for customers in these markets;



•

the potential for revenue enhancement, including by offering existing El Dorado customers increased credit availability and a broader range of, and expanded access to, financial products and services from a larger institution, which create the opportunity for PacWest to have greater future earnings and prospects compared to PacWest's earnings and prospects on a stand-alone basis;



•

the potential risks associated with successfully integrating El Dorado's business, operations and workforce with those of Pacific Western Bank, and PacWest's past record of successfully integrating acquisitions;



•

its review and discussions with PacWest's management and advisors concerning the due diligence examination of El Dorado;

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•

management's expectation that PacWest will continue to have a strong capital position upon completion of the transaction;



•

its review with its legal advisor, Sullivan & Cromwell LLP, of the merger agreement and other agreements, including the provisions of the merger agreement designed to enhance the probability that the transaction will be completed;



•

the potential risk of diverting management attention and resources from the operation of PacWest's business and towards the completion of the merger and the integration of El Dorado; and



•

the regulatory and other approvals required in connection with the merger and the expected likelihood that such regulatory approvals will be received in a reasonably timely manner and without the imposition of unacceptable conditions.

        The foregoing discussion of the information and factors considered by the PacWest board of directors is not intended to be exhaustive, but includes the material factors considered by the PacWest board of directors. In reaching its decision to approve the merger agreement, the merger and the other transactions contemplated by the merger agreement, the PacWest board of directors did not quantify or assign any relative weights to the factors considered, and individual directors may have given different weights to different factors. The PacWest board of directors considered all these factors as a whole, including discussions with, and questioning of, PacWest's senior management and PacWest's advisors, and overall considered the factors to be favorable to, and to support its determination to approve entering into the merger agreement.

        This explanation of PacWest's reasons for the merger and other information presented in this section is forward-looking in nature and should be read in light of the section entitled "Cautionary Statement Regarding Forward-Looking Statements."

        PacWest's board of directors realized that there can be no assurance about future results, including results expected or considered in the factors listed above, such as assumptions regarding enhanced business prospects, anticipated cost savings and earnings accretion/dilution. The PacWest board of directors concluded, however, that the potential positive factors outweighed the potential risks of completing the transaction.

Management and Board of Directors of Pacific Western Bank After the Merger

        The directors and officers of Pacific Western Bank immediately prior to the effective time will be the directors and officers of the surviving bank after the consummation of the merger, and will serve until such time as their successors are duly elected and qualified.

Interests of El Dorado Directors and Executive Officers in the Merger

        In considering the recommendation of the El Dorado board of directors with respect to the merger, El Dorado shareholders should be aware that certain directors and executive officers of El Dorado have interests in the merger that may be different from, or in addition to, the interests of El Dorado shareholders generally. The El Dorado board of directors was aware of these interests and considered them, among other matters, in approving the merger agreement and the transactions contemplated thereby and in making its recommendation that El Dorado shareholders vote to approve the El Dorado merger proposal. These interests are described in further detail below.

Stock Ownership

        The directors and executive officers of El Dorado, as a group, beneficially owned and had the power to vote as of September 11, 2018, a total of 10,719 shares of El Dorado common stock,

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representing approximately 7.67% of the outstanding shares of El Dorado common stock as of that date. All of these shares are expected to be voted in favor of the merger agreement, with 8,469 shares of El Dorado common stock, representing 6.06% of the outstanding shares of El Dorado common stock, subject to the voting agreements entered into by each of the directors of El Dorado who own shares of El Dorado common stock. Please see "The Merger Agreement—Voting Agreements" beginning on page 91. Each of these persons will be entitled to receive the same merger consideration for their shares of El Dorado common stock as the other El Dorado shareholders.

New Agreements with PacWest

Consulting Agreements

        In connection with the execution of the merger agreement, PacWest and Pacific Western Bank entered into consulting agreements with Thomas C. Meuser, Chairman of the Board, George L. Cook, Jr., Chief Executive Officer and a director of El Dorado, and William H. Blucher, Chief Financial Officer and a director of El Dorado, whereby PacWest will retain these three executive officers as consultants to Pacific Western Bank to perform certain services, including providing strategic advice and counsel to Pacific Western Bank for Messrs. Meuser and G. Cook and acting as ambassadors to Pacific Western Bank in dealings with clients and counterparties for all three executives. The consulting agreements become effective as of, and are conditioned upon, the closing of the merger. If the merger agreement is terminated pursuant to its terms, the consulting agreements will also terminate and be of no force or effect. The term of the consulting agreements will end on the earlier of (A)(1) 6 months from the closing of the merger, in the case of Mr. Meuser, (2) 12 months from the closing of the merger, in the case of Mr. G. Cook, or (3) 18 months from the closing of the merger, in the case of Mr. Blucher, and (B) the termination of the respective consulting agreement pursuant to its terms.

        Pursuant to his consulting agreement, Mr. Blucher has agreed not to, without the written consent of PacWest or Pacific Western Bank, directly or indirectly, represent, become employed by, perform services for, consult to, or advise in any manner or have any material interest in any "competitive enterprise" during the term of the consulting agreement. "Competitive enterprise" is defined as (i) any banking organization or other business that offers lending, deposit taking or other banking products or services that competes anywhere within PacWest's "footprint" (i.e., where PacWest or any of its subsidiaries regularly conducts business) with any of the business activities engaged in by PacWest or any of its subsidiaries at any time during the term of the consulting agreement or (ii) any entity or business attempting to acquire an interest in such a banking organization. Messrs. Meuser's and G. Cook's consulting agreements reference non-compete covenants in their respective non-competition and non-solicitation agreements entered into with PacWest, as more fully described in "—Non-Competition and Non-Solicitation Agreements" below.

        Further, all consulting agreements reference non-solicit restrictive covenants in their respective non-competition and non-solicitation agreements, in the cases of Messrs. Meuser and G. Cook, and the non-solicitation agreement, in the case of Mr. Blucher. For a more complete description of the non-solicitation covenants, see "—Non-Competition and Non-Solicitation Agreements" below.

        In addition, each of Messrs. Meuser, G. Cook, and Blucher agreed, pursuant to the terms of their respective consulting agreements, not to divulge trade secrets and confidential information, knowledge or data relating to PacWest and its subsidiaries, including Pacific Western Bank, and their businesses and investments, obtained during their employment with El Dorado and during their consulting with Pacific Western Bank.

        Messrs. Meuser, G. Cook, and Blucher will receive for their services following consummation of the merger, subject to complying with the restrictive covenants and confidentiality provisions of the (i) consulting agreements and (ii) non-solicitation and non-competition agreements, in the cases of

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Messrs. Meuser and G. Cook, and non-solicitation agreement, in the case of Mr. Blucher, the following total consulting fees: (1) $33,000 for Mr. Meuser, (2) $190,000 for Mr. G. Cook, and (3) $145,000 for Mr. Blucher; in each case, payable as a single lump sum payment on the date of, or as soon as reasonably practicable following, the closing of the merger. However, if a consulting agreement is terminated before its scheduled expiration either (x) by Pacific Western Bank for Cause (as defined in each consulting agreement), (y) by the respective executive officer of El Dorado for any reason, or (z) due to the death or disability of the respective El Dorado executive officer, then such El Dorado executive officer must immediately repay to Pacific Western Bank a pro rata portion of his consulting fee representing the unperformed services for the remainder of the term under his respective consulting agreement. The consulting agreements also provide for reimbursement of each of the executive officer's reasonable out-of-pocket expenses, as well as office space at El Dorado's Placerville branch location.

Offer Letter

        John A. Cook has entered into a written offer letter with Pacific Western Bank to be employed as a regional president of the Sierra Region of Pacific Western Bank with a start date following the closing of the merger. Pursuant to the offer letter, in addition to an annual salary of $240,000 less statutory deductions, Mr. J. Cook will also be eligible to accrue paid time off and continue to have access to a Pacific Western Bank-owned car as well as participate in Pacific Western Bank's health benefits and 401(k) plan. If Mr. J. Cook remains an employee of Pacific Western Bank for a period of time to be mutually agreed upon by Mr. J. Cook and Pacific Western Bank, currently estimated to be the one year anniversary of the closing of the merger, then he is eligible for a retention bonus of $100,000, less statutory deductions, to be paid in a lump sum, payable within 60 days following the date of termination of employment.

Non-Competition and Non-Solicitation Agreements

        Shareholder Director Non-Solicitation and Non-Competition Agreements.    As a condition of and inducement for PacWest to enter into the merger agreement, each of the three El Dorado directors who own shares of El Dorado common stock (Messrs. Meuser, G. Cook and Teichert) entered into a non-solicitation and non-competition agreement with PacWest. Pursuant to such agreements, the foregoing directors have agreed that, without the written consent of PacWest, they will not, directly or indirectly, own, manage, operate, be employed by, control, or otherwise carry on, participate in the ownership, management, operation or control of, or engage in any competitive enterprise during the period from the closing date of the merger until the fifth anniversary of the end of such director's employment or service as a director or officer of El Dorado, referred to as the restricted period.

        Additionally, such agreements also provide that, during the restricted period, the foregoing directors and each of their affiliates are prohibited from, without the prior written consent of PacWest, directly or indirectly: (i) soliciting any client to transact business with a competitive enterprise or to reduce or refrain from doing any business with PacWest or any of its subsidiaries (including El Dorado), (ii) transacting business with any client that would cause such director or any of his affiliates to be a competitive enterprise, (iii) interfering with or damaging any relationship of PacWest, Pacific Western Bank or El Dorado, on the one hand, and a client, on the other hand and (iv) soliciting any employee of PacWest or any of its subsidiaries (or who was an employee of PacWest or any of its subsidiaries within the prior 90 days) to resign or to apply for or accept employment with any other business or enterprise.

        Non-Shareholder Director Non-Solicitation Agreements.    As a condition of and inducement for PacWest to enter into the merger agreement, all directors who do not own shares of El Dorado common stock entered into a non-solicitation agreement with PacWest. Messrs. Blucher, Cefalu, Combellack, Cornelius, Coyle and Naygrow have each entered into a non-solicitation agreement. Such

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agreements, among other things, provide the same restrictions on solicitation as in the non-solicitation and non-competition agreements described above.

Indemnification and Insurance

        Pursuant to the terms of the merger agreement, following the effective time, PacWest has agreed to, or will cause the surviving bank to, indemnify present and former directors, officers and, to the extent required by El Dorado's charter and bylaws (in each case, as in effect as of the date of the merger agreement), each employee of El Dorado (determined as of the effective time) in connection with any claim arising out of actions or omissions occurring at or prior to the effective time to the fullest extent permitted under law and under El Dorado's charter and bylaws (in each case, as in effect as of the date of the merger agreement).

        For a period of six years from the effective time, PacWest has agreed to, or cause the surviving bank to, provide, the portion of directors' and officers' liability insurance that serves to reimburse the present and former directors and officers of El Dorado on terms and conditions no less advantageous to such officers and directors than those provided by El Dorado; provided, however, that PacWest and the surviving bank are not required to spend more than 250% of the current annual amount spent by El Dorado to procure such insurance coverage. In lieu thereof, PacWest may, or may cause the surviving bank to, purchase a six-year tail policy subject to the limitation on cost described in the preceding sentence.

Payments Upon Termination or Change in Control

Executive Salary Continuation Agreements

        Messrs. Meuser, G. Cook, J. Cook and Blucher, collectively, El Dorado's four executive officers, previously entered into salary continuation agreements, as amended and referred to as the SCAs, with El Dorado. The SCAs provide El Dorado's executive officers with a termination benefit equal to the product of (i) 300% of the base salary of the executive officer times (ii) a fraction, the numerator of which is 1095 minus the number of days from the date of the change in control to the date of termination and the denominator of which is 1095, payable upon termination of employment for any reason other than for cause, including voluntary resignation, within 36 months following a change in control of El Dorado. The base salary of the El Dorado executive officer includes the annual salary and the total of all discretionary bonuses paid to the executive officer during the 12 months immediately preceding a change in control. Such termination benefit is to be paid as a lump sum at termination.

        Each of El Dorado's four executive officers entered into a first amendment to their respective SCA, so that any severance benefits under the SCAs that would constitute "excess parachute payments" within the meaning of Section 280G of the Internal Revenue Code will be reduced in order to result in no portion of such payments being subject to the excise tax imposed by Section 4999 of the Internal Revenue Code.

        The following table sets forth the estimated value of the cash severance payments to which El Dorado's executive officers would be entitled pursuant to the SCAs based on anticipated compensation levels for 2019, in the event of and assuming closing of the merger on January 31, 2019 and a

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termination of employment immediately following closing of the merger on such date. The actual amounts, if any, to be received by the executive officers may differ from the amounts set forth below.

Regulatory Approvals Required for the Merger

        Completion of the merger by El Dorado is subject to the requirement that all consents, registrations, approvals, permits and authorizations required to be obtained prior to the effective time by either party or any of its respective subsidiaries from the FDIC and the CDBO which are necessary to consummate the merger, and any other consents, registrations, approvals, permits and authorizations from any governmental authority the failure of which to be obtained is reasonably likely to have, individually or in the aggregate, a material adverse effect on PacWest (measured on a scale relative to El Dorado) or on El Dorado, have been made or obtained (as the case may be) and remain in full force and effect and all statutory waiting periods in respect thereof have expired.

        Completion of the merger by PacWest is subject to the requirement that all consents, registrations, approvals, permits and authorizations required to be obtained prior to the effective time by either party or any of its respective subsidiaries from the FDIC and the CDBO which are necessary to consummate the merger, and any other consents, registrations, approvals, permits and authorizations from or with any governmental authority the failure of which to be obtained is reasonably likely to have, individually or in the aggregate, a material adverse effect on PacWest (measured on a scale relative to El Dorado) or on El Dorado, have been made or obtained (as the case may be) and remain in full force and effect and all statutory waiting periods in respect thereof have expired, and none of such consents, registrations, approvals, permits and authorizations contain any "materially burdensome regulatory condition." The merger agreement defines a "materially burdensome regulatory condition" to mean any condition that would reasonably be likely following the effective time to (i) have a material adverse effect with respect to either PacWest (measured on a scale relative to El Dorado) or El Dorado or (ii) require PacWest, Pacific Western Bank or the surviving bank to raise additional capital in an amount that would, in the good faith judgment of PacWest, materially reduce the economic benefits of the merger to PacWest or the holders of PacWest common stock (including the El Dorado shareholders in respect of the shares of PacWest common stock received by them in the merger) or (iii) require the sale by El Dorado or PacWest or the surviving bank of any material portion of their respective assets.

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        A notice must be submitted to the Office of the Comptroller of the Currency, referred to as the OCC, advising the OCC of the merger. Notifications and/or applications requesting approval may also be submitted to various other federal and state regulatory authorities and self-regulatory organizations.

        PacWest and El Dorado have agreed to cooperate and to use their respective reasonable best efforts to prepare and file, or in the case of PacWest cause to be filed, all documentation to effect all necessary notices, reports and other filings and to obtain all permits, consents, approvals and authorizations necessary or advisable to be obtained from any third parties and/or governmental authorities in order to consummate the merger or any of the other transactions contemplated by the merger agreement. PacWest, El Dorado and/or their respective subsidiaries have filed applications and notifications to obtain these regulatory approvals.

        Although the parties currently believe they should be able to obtain all required regulatory approvals in a timely manner, they cannot be certain when or if they will obtain them or, if obtained, whether they will contain terms, conditions or restrictions not currently contemplated that will be detrimental to PacWest after the completion of the merger or will contain a materially burdensome regulatory condition.

Federal Deposit Insurance Corporation

        The prior approval of the FDIC is required under Section 18(c) of the Federal Deposit Insurance Act, referred to as the Bank Merger Act, to merge El Dorado with and into Pacific Western Bank. In evaluating an application filed under the Bank Merger Act, the FDIC generally considers: (1) the competitive impact of the transaction, (2) financial and managerial resources of each bank that is a party to the bank merger, (3) the extent to which the bank merger would result in greater or more concentrated risks to the stability of the U.S. banking or financial system, (4) the convenience and needs of the communities in which the banks serve, (5) whether the merger is subject to the Riegle-Neal Interstate Banking and Branching Efficiency Act of 1994, (6) the performance records of the banks under the Community Reinvestment Act of 1977 and the regulations issued thereunder, referred to as the CRA, including their CRA rating and (7) each of the banks' effectiveness in combating money-laundering activities. In connection with its review under the Bank Merger Act, the FDIC will provide an opportunity for public comment on the application for the merger, and is authorized to hold a public meeting or other proceeding if it determines that would be appropriate.

        Transactions approved by the FDIC generally may not be completed until 30 days after such approval is received, during which time the Department of Justice, referred to as the DOJ, may challenge the transaction on antitrust grounds. With the approval of the FDIC and the concurrence of the DOJ, the waiting period may be reduced to no less than 15 days. The commencement of an antitrust action would stay the effectiveness of such an approval unless a court specifically ordered otherwise. In reviewing the merger, the DOJ could analyze the merger's effects on competition differently than the FDIC, and thus it is possible that the DOJ could reach a different conclusion regarding the merger's effects on competition. A determination by the DOJ not to object to the merger may not prevent the filing of antitrust actions by private persons or state attorneys general.

California Department of Business Oversight

        The prior approval of the CDBO is required under the California Financial Code to merge El Dorado with and into Pacific Western Bank. In reviewing the merger of El Dorado with Pacific Western Bank, the CDBO will take competitive considerations into account, as well as capital adequacy, quality of management and earnings prospects, in terms of both quality and quantity. The CDBO will also take into account the record of performance of the banks concerned in meeting the credit needs of the entire community, including low- and moderate-income neighborhoods, served by such depository institutions. The CDBO will also take into account the safety and soundness of the

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resulting bank following the merger. In considering the merger, the California Financial Code also requires the CDBO to consider the fairness of the merger to all parties involved.

Additional Regulatory Approvals and Notices

        Notice is required to be provided to the OCC under 12 C.F.R. § 5.33 to merge El Dorado with and into Pacific Western Bank. Notifications and/or applications requesting approval may be submitted to various other federal and state regulatory authorities and self-regulatory organizations.

        Although PacWest and El Dorado expect to obtain the required regulatory approvals, there can be no assurances as to if, or when, these regulatory approvals will be obtained, the terms and conditions on which the approvals may be granted, or whether there will be litigation challenging such approvals. There can likewise be no assurances that U.S. or state regulatory authorities will not attempt to challenge the merger on antitrust grounds or for other reasons, or, if such a challenge is made, as to the result of any such challenge.

Accounting Treatment

        In accordance with current accounting guidance, Pacific Western Bank, as the acquirer, will account for the merger using the acquisition method. The acquisition method requires that (a) the recorded assets and liabilities of Pacific Western Bank will be carried forward at their recorded amounts, (b) Pacific Western Bank's historical operating results will be unchanged for the prior periods being reported on, (c) the assets and liabilities of El Dorado will be adjusted to fair value at the date of the merger and combined with the assets and liabilities of Pacific Western Bank, and (d) the operating results of El Dorado will be included in the operating results of Pacific Western Bank beginning from the date of completion of the merger. In addition, all identifiable intangible assets will be recorded at fair value and included as part of the assets acquired. The amount by which the purchase price, consisting of the value of the cash and shares of PacWest common stock to be issued to former holders of shares of El Dorado common stock, exceeds the fair value of the net assets including identifiable intangible assets of El Dorado at the merger date will be reported as goodwill. In accordance with current accounting guidance, goodwill is not amortized and will be evaluated for impairment annually. Identified intangible assets will be amortized over their estimated lives.

Public Trading Markets

        PacWest common stock is listed on NASDAQ under the symbol "PACW." The PacWest common stock issuable in the merger will be listed on NASDAQ. There is no established public trading market for shares of El Dorado common stock and no broker makes a market in the stock.

Exchange of Shares in the Merger

        At or prior to the effective time, PacWest will appoint an exchange agent to handle the exchange of shares of El Dorado common stock for shares of PacWest common stock. Promptly after the effective time (and in any event within five business days), the exchange agent will send to each holder of record of shares of El Dorado common stock at the effective time (other than holders of certain specified excluded shares or dissenting shares) appropriate transmittal materials and instructions for effecting the exchange of shares of El Dorado common stock for the merger consideration the holder is entitled to receive under the merger agreement. Upon surrender of certificates or book entry shares for cancellation along with the other documents described in the instructions, an El Dorado shareholder will receive a certificate (or evidence of shares in book-entry form, as applicable) representing the number of whole shares of PacWest common stock that such holder is entitled to receive based on the exchange ratio of 58.2209 for each share of El Dorado common stock and a check in the amount (after giving effect to any required tax withholdings and subject to any adjustments as provided in the merger

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agreement) of the cash consideration for the surrendered shares, and any cash payable in lieu of fractional shares plus any unpaid non-stock dividends and any other dividends or other distributions that such holder has the right to receive pursuant to the merger agreement. After the effective time, El Dorado will not register any transfers of shares of El Dorado common stock.

Dissenters' Rights

        El Dorado shareholders who vote their shares of El Dorado common stock "AGAINST" the merger proposal or who have given notice in writing to El Dorado at or prior to the special meeting that they dissent from the merger and who properly demand the purchase of such shares in accordance with 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a will not be converted into the right to receive the merger consideration otherwise payable for shares of El Dorado common stock upon consummation of the merger, but will instead be converted into the right to receive such consideration as may be determined to be due pursuant to 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a. A copy of 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a is attached to this proxy statement/prospectus as Appendix C.

        The following discussion is not a complete statement of the law pertaining to dissenters' rights under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a. The full text of 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a is attached to this proxy statement/prospectus as Appendix C and is incorporated herein by reference. Appendix C should be reviewed carefully by any El Dorado shareholder who wishes to exercise dissenters' rights or who wishes to preserve the right to do so, since failure to comply with the procedures of the relevant statute in any respect will result in the loss of dissenters' rights.

        All references in 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a and in this summary to a "shareholder" are to the holder of record of shares of El Dorado common stock as to which dissenters' rights are asserted. A person having a beneficial interest in shares of El Dorado common stock held of record in the name of another person, such as a broker, bank or nominee, cannot enforce dissenters' rights directly and must act promptly to cause the holder of record to follow the steps summarized below properly and in a timely manner to perfect such person's dissenters' rights.

        ANY HOLDER OF SHARES OF EL DORADO COMMON STOCK WISHING TO EXERCISE DISSENTERS' RIGHTS IS URGED TO CONSULT LEGAL COUNSEL BEFORE ATTEMPTING TO EXERCISE SUCH RIGHTS. FAILURE TO COMPLY STRICTLY WITH ALL OF THE PROCEDURES SET FORTH IN 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a WILL RESULT IN THE LOSS OF A SHAREHOLDER'S STATUTORY DISSENTERS' RIGHTS.

        Under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a, shares of El Dorado common stock must satisfy each of the following requirements to qualify as dissenting shares, which are referred to as dissenting shares:

•

such dissenting shares must have voted "AGAINST" the merger proposal or the holder of such dissenting shares must have given notice in writing to El Dorado at or prior to the special meeting that such holder dissents from the merger; AND



•

the holder of such dissenting shares must make a timely written request to the surviving bank, accompanied by the surrender of such holder's share certificates.

        A vote "AGAINST" the merger proposal does not in and of itself constitute a demand for appraisal under federal law.

        Pursuant to 12 U.S.C. § 214a, holders of dissenting shares may be entitled to receive in cash the value of the shares held by such holders, if and when the merger is consummated, upon written request made to the surviving bank at any time before 30 days after the date of consummation of the merger, accompanied by the surrender of such holders' stock certificates, if applicable. The value of such shares

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will be determined as of the date on which the shareholders' meeting was held authorizing the merger, by a committee of three persons, one to be selected by majority vote of the dissenting shareholders entitled to receive the value of their shares, one by the directors of the resulting surviving bank and the third by the two so chosen.

        The valuation agreed upon by any two of three chosen appraisers will govern; but, if the value determined by the appraisers is not satisfactory to any dissenting shareholder who has requested payment, such shareholder may within five days after being notified of the appraised value of his shares appeal to the OCC, who must cause a reappraisal to be made, which will be final and binding as to the value of the shares of the appellant. If, within 90 days from the date of consummation of the merger, for any reason one or more of the appraisers is not selected as provided in 12 U.S.C. § 214a, or the appraisers fail to determine the value of the shares, the OCC must upon written request of any interested party, cause an appraisal to be made, which will be final and binding on all parties. The expenses of the OCC in making the reappraisal as the case may be, must be paid by the surviving bank.

        El Dorado shareholders considering whether to exercise dissenters' rights should consider that the value of their shares of El Dorado common stock determined under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a could be more than, the same as or less than the value of consideration to be paid in connection with the merger, as set forth in the merger agreement. Also, the surviving bank reserves the right to assert in any appraisal proceeding that, for purposes thereof, the value of dissenting shares is less than the value of the merger consideration to be issued and paid in connection with the merger, as set forth in the merger agreement. El Dorado shareholders considering whether to exercise dissenters' rights should consult with their tax advisors for the specific tax consequences of the exercise of dissenters' rights.

        Strict compliance with certain technical prerequisites is required to exercise dissenters' rights. El Dorado shareholders wishing to exercise dissenters' rights should consult with their own legal counsel in connection with compliance with 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a. Any El Dorado shareholder who fails to comply with the requirements of 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a, attached as Appendix C to this proxy statement/prospectus, will forfeit the right to exercise dissenters' rights and will, instead, receive the consideration to be issued and paid in connection with the merger, as set forth in the merger agreement.

        Except as expressly limited by 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a, dissenting shares continue to have all the rights and privileges incident to their shares until the value of their shares is agreed upon or determined.

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THE MERGER AGREEMENT

        The following is a summary of selected provisions of the merger agreement. While PacWest and El Dorado believe this description covers the material terms of the merger agreement, it may not contain all of the information that is important to you and is qualified in its entirety by reference to the merger agreement, which is incorporated by reference in its entirety into, and is attached as Appendix A to, this document. The parties urge you to read the merger agreement in its entirety.

Explanatory Note

        The merger agreement and the summary of its terms in this document have been included only to provide you with information about the terms and conditions of the merger agreement. The representations, warranties and covenants contained in the merger agreement are made by PacWest and El Dorado only for purposes of the merger agreement and as of specific dates and were qualified and subject to certain limitations and exceptions agreed to by PacWest and El Dorado in connection with negotiating the terms of the merger agreement. In particular, in your review of the representations and warranties contained in the merger agreement and described in this summary, it is important to bear in mind that the representations and warranties were made solely for the benefit of the parties to the merger agreement and were negotiated for the purpose of allocating contractual risk among the parties to the merger agreement rather than to establish matters as facts. Shareholders are not third-party beneficiaries under the merger agreement. The representations and warranties may also be subject to a contractual standard of materiality or material adverse effect different from those generally applicable to shareholders and reports and documents filed with the SEC, and, in some cases, they may be qualified by disclosures made by one party to the other, which are not necessarily reflected in the merger agreement or other public disclosures made by PacWest or El Dorado. The representations and warranties contained in the merger agreement do not survive the effective time. Moreover, information concerning the subject matter of the representations, warranties and covenants, which do not purport to be accurate as of the date of this document, may have changed since the date of the merger agreement, and subsequent developments or new information may not be fully reflected in public disclosures of PacWest or El Dorado.

        For the foregoing reasons, the representations, warranties and covenants or any descriptions of those provisions should not be read alone or relied upon as characterizations of the actual state of facts or condition of PacWest or El Dorado or any of their respective subsidiaries or affiliates. Instead, such provisions or descriptions should be read only in conjunction with the other information provided elsewhere in this document or incorporated by reference into this document. Please see the section entitled "Where You Can Find More Information." PacWest will provide additional disclosures in its public reports to the extent they are aware of the existence of any material facts that are required to be disclosed under federal securities laws and that might otherwise contradict the terms and information contained in the merger agreement and will update such disclosure as required by federal securities laws.

The Merger

        Upon the terms and subject to the conditions of the merger agreement, El Dorado will merge with and into Pacific Western Bank, a California state-chartered bank and wholly owned subsidiary of PacWest, with Pacific Western Bank as the surviving bank. The separate existence of El Dorado will cease, with all its rights, privileges, immunities, power and franchises.

Effects of the Merger

        As a result of the merger, the shares of El Dorado common stock will no longer be outstanding and will automatically be cancelled and retired and cease to exist. El Dorado shareholders will only participate in PacWest's future earnings and potential growth through their ownership of PacWest common stock. All of the other incidents of direct ownership of shares of El Dorado common stock,

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such as the right to vote on certain decisions with respect to El Dorado, to elect directors to the El Dorado board of directors and to receive dividends and distributions from El Dorado, will be extinguished upon completion of the merger. All of the property, rights, privileges and powers of Pacific Western Bank and El Dorado will vest in the surviving bank, and all obligations, liabilities, debts, restrictions, disabilities and duties of Pacific Western Bank and El Dorado will become the obligations, liabilities, debts, restrictions, disabilities and duties of the surviving bank.

Closing and Effective Time of the Merger

        The merger agreement provides that the merger will be consummated no later than three business days after the satisfaction or waiver of all the closing conditions, except for those conditions that by their nature are to be satisfied at the closing (but subject to the fulfillment or waiver of those conditions), including the receipt of all regulatory and shareholder approvals and after the expiration of all regulatory waiting periods, unless extended by mutual written agreement of PacWest and El Dorado. The merger will become effective at the time a copy of the agreement of merger certified by the Secretary of State of the State of California has been filed with the CDBO in accordance with Section 4887 of the California Financial Code. The parties are seeking regulatory approval by the first quarter of 2019, with the consummation of the merger to occur as soon as practicable thereafter. However, there can be no assurance as to when or if the merger will occur.

        If the merger is not completed by the end date, the merger agreement may be terminated by either PacWest or El Dorado, except to the extent that the failure of the merger to be consummated by that date arises out of or results from the knowing action or inaction of the party seeking to terminate which action or inaction is in violation of its obligations under the merger agreement.

        For a description of the transaction structure and merger consideration, please see the section entitled "The Merger—Terms of the Merger."

Pacific Western Bank's Governing Documents, Directors and Officers Following the Closing

Governing Documents

        The charter and bylaws of Pacific Western Bank will be the charter and bylaws of the surviving bank as they exist immediately before the effective time, in each case until thereafter changed or amended as provided therein or by applicable law.

Directors and Officers

        The directors and officers of Pacific Western Bank immediately prior to the effective time will be the directors and officers of the surviving bank until the earlier of their resignation or removal or until their respective successors are duly appointed and qualified.

Merger Consideration

Conversion of El Dorado Common Stock

        At the effective time, each share of El Dorado common stock, other than excluded shares and dissenting shares as described below, issued and outstanding immediately prior to the effective time will be converted into the right to receive the merger consideration consisting of (i) $427.92 in cash and (ii) 58.2209 shares of PacWest common stock, subject to adjustments as set forth in the merger agreement and as further described under sections entitled "—Merger Consideration" and "—Termination of the Merger Agreement."

        Pursuant to the terms of the merger agreement, PacWest (i) has ordered title commitments, surveys and title documents for real property owned by El Dorado in order to determine, as provided

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in the merger agreement, whether there are any defects to the title of such real property and (ii) will obtain certain environmental examinations of real property owned by El Dorado in order to determine, as provided in the merger agreement, whether certain environmental conditions exist on such real property. If certain title defects and/or environmental conditions exist with respect to El Dorado's real property and the total cost to cure and/or remediate such defects or conditions (after taking into account any tax credits, deductions or benefits or insurance coverage, in each case, that the parties agree are reasonably likely to be available) is greater than $2,000,000, the aggregate cash consideration will be reduced by the real property adjustment amount, except that if the real property adjustment amount exceeds $7,000,000, then in lieu of reducing the cash consideration by 100% of the excess adjustment amount, the merger consideration shall be reduced as follows: (a) 12.5% of the excess adjustment amount shall be applied to reduce the cash consideration and (b) the remaining 87.5% of the excess adjustment amount shall be applied to reduce the share component of the merger consideration by reducing the exchange ratio to reflect the reduction in the merger consideration.

Cancellation of Excluded Shares and Dissenting Shares

        At the effective time, (i) any shares of El Dorado common stock held by PacWest or any direct or indirect wholly-owned subsidiary of PacWest or by El Dorado or any wholly-owned subsidiary of El Dorado, other than those held in a fiduciary capacity or as a result of debts previously contracted, which are referred to as excluded shares, and (ii) any dissenting shares (subject to the procedures for dissenting shares described herein) will automatically be cancelled and retired and will cease to exist and no consideration will be issued in exchange therefor.

Dissenting Shares

        To the extent dissenters' rights under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a are applicable to the merger, no dissenting shares will be converted into or represent a right to receive the consideration for such shares set forth in merger agreement. Instead, holders of dissenting shares will be entitled to receive in cash the value of the shares held by such holder to the extent granted by 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a. If a holder of dissenting shares thereafter effectively withdraws or loses such dissenters' rights with respect to such shares then, as of the occurrence of such withdrawal or loss, each such share will be deemed as of the effective time to have been converted into and represent only the right to receive the consideration for such shares set forth in the merger agreement.

        For more information regarding dissenters' rights, please see the section entitled "The Merger—Dissenters' Rights."

Rights as Shareholders of El Dorado

        At the effective time, holders of shares of El Dorado common stock will cease to be, and will have no rights as, shareholders of El Dorado other than to receive the merger consideration and any dividends or distributions to which they are entitled under the merger agreement.

Exchange Procedures

        Immediately prior to the effective time, PacWest will deposit (or cause to be deposited) with an exchange agent selected by PacWest with El Dorado's prior approval (such approval not to be unreasonably withheld or delayed) (i) an amount of cash equal to $427.92 in cash, subject to adjustment as set forth in the merger agreement and described in this proxy statement/prospectus multiplied by the number of El Dorado shares (other than excluded shares and dissenting shares) outstanding immediately prior to the effective time, plus any cash due in lieu of fractional shares, and (ii) certificates, or evidence of shares in book-entry form, representing the shares of PacWest common

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stock to be exchanged for shares of El Dorado common stock in the merger. Promptly after the effective time (and in any event within five business days), the exchange agent will provide appropriate transmittal materials to holders of record of shares of El Dorado common stock, advising such holders of the procedure for surrendering their shares to the exchange agent.

        Upon the surrender of certificate(s) of shares of El Dorado common stock (or affidavits of loss in lieu thereof) or evidence of shares in book-entry form, the holder will be entitled to receive in exchange therefor:

•

a number of whole shares of PacWest common stock that such holder is entitled to receive pursuant to the merger agreement, as described in "—Conversion of El Dorado Common Stock" above, evidenced by a stock certificate or in book-entry form; and



•

a check in the amount of the cash consideration for the surrendered shares and any cash payable in lieu of fractional shares plus any unpaid non-stock dividends and any other dividends or other distributions that such holder has the right to receive pursuant to the merger agreement.

Distributions with Respect to Unexchanged Shares

        All shares of PacWest common stock to be issued pursuant to the merger will be deemed issued and outstanding as of the effective time and if a dividend or other distribution is declared by PacWest in respect of the PacWest common stock, the record date for which is at or after the effective time, that declaration will include dividends or other distributions in respect of all shares issuable pursuant to the merger agreement. No dividends or other distributions in respect of PacWest common stock will be paid to any holder of any unsurrendered certificate or book-entry shares representing shares of El Dorado common stock until such certificate (or affidavit of loss in lieu thereof) or book-entry shares are surrendered for exchange in accordance with the merger agreement. Subject to applicable laws, following surrender of any such certificate (or affidavit of loss in lieu thereof as provided) or book-entry shares, there will be issued and/or paid to the holder of a certificate or evidence of shares in book-entry form, as applicable, representing whole shares of PacWest common stock issued in exchange therefor, without interest, (i) at the time of such surrender, the dividends or other distributions with a record date after the effective time theretofore payable with respect to such whole shares of PacWest common stock and not paid and (ii) at the appropriate payment date, the dividends or other distributions payable with respect to such whole shares of PacWest common stock with a record date after the effective time but with a payment date subsequent to surrender.

Fractional Shares of PacWest Common Stock

        No fractional shares of PacWest common stock will be issued to any shareholder of El Dorado upon completion of the merger. For each fractional share that would otherwise be issued, PacWest will pay cash in an amount equal to the fraction of a share (rounded to the nearest thousandth) of PacWest common stock which the holder would otherwise be entitled to receive multiplied by the PacWest average closing price. No interest will be paid or accrue on cash payable to holders in lieu of fractional shares.

Representations and Warranties

        The merger agreement contains representations and warranties on the part of El Dorado as to, among other things:

•

organization, standing and authority;



•

capital stock;

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•

the organization and existence of any subsidiaries;



•

power;



•

authority;



•

no conflicts, third party consents and governmental and regulatory approvals required to complete the merger;



•

required filings;



•

availability, accuracy and compliance with GAAP of financial reports and filings with regulatory authorities;



•

timely filing of required regulatory reports and absence of regulatory investigations or restrictive agreements with regulators;



•

absence of litigation;



•

compliance with restrictive agreements with regulators;



•

compliance with 12 U.S.C. § 1851 and the regulations promulgated thereunder, known as the Volcker Rule;



•

compliance with laws and permits;



•

material contracts;



•

no broker's or finder's fees, except as contemplated by the merger agreement;



•

employee benefit plans;



•

labor matters;



•

environmental matters;



•

tax matters;



•

interest rate risk management instruments, such as swaps and options;



•

proper and accurate maintenance of books and records;



•

insurance coverage;



•

validity and status of loans;



•

adequacy of its allowance for loan losses under established regulatory and accounting standards;



•

transactions with affiliates;



•

conditions of and title to real and personal property;



•

intellectual property and IT assets;



•

no broker-dealer or investment adviser subsidiary;



•

exemptions from takeover statutes; and



•

mortgage-lending business.

        The merger agreement also contains representations and warranties on the part of PacWest as to, among other things:

•

organization, standing and authority;



•

capital stock;

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•

corporate power;



•

corporate authority;



•

no conflicts, third party consents and governmental and regulatory approvals required to complete the merger;



•

required filings;



•

availability, accuracy and compliance with GAAP and filings with the SEC and regulatory authorities;



•

absence of litigation;



•

absence of restrictive agreements with regulators;



•

compliance with laws and permits;



•

no broker's or finder's fees, except as contemplated by the merger agreement; and



•

tax matters.

        Certain of these representations and warranties are qualified as to "materiality" or "material adverse effect." For purposes of the merger agreement, a "material adverse effect" with respect to PacWest or El Dorado, as the case may be, means any effect, circumstance, occurrence or change that (i) is material and adverse to the business, assets or deposit liabilities, properties, operations, results of operations, or condition (financial or otherwise) of El Dorado and its subsidiaries or PacWest and its subsidiaries, as the case may be, or (ii) materially impairs the ability of such party to consummate the merger and the transactions contemplated by the merger agreement on a timely basis. However, none of the following effects, circumstances, occurrences or changes will be considered when determining if a material adverse effect has occurred:

•

any change in law or GAAP or interpretations thereof (except to the extent that such effect, circumstance, occurrence or change disproportionately adversely affects El Dorado and its subsidiaries or PacWest and its subsidiaries, as the case may be, compared to other companies of similar size and operating in the commercial banking industry in which such party operates, in which case only the disproportionate effect will be taken into account);



•

effects resulting from worsening of geopolitical conditions in the United States or any other country in which El Dorado or PacWest and any of its respective subsidiaries conduct material operations or acts of war, sabotage or terrorism (including any escalation or general worsening of any such acts of war, sabotage or terrorism) in the United States or any other country in which either party and any of its respective subsidiaries conduct material operations;



•

in the case of PacWest, any change in market price or trading volume of PacWest common stock (except that the facts or circumstances giving rise or contributing to such change may be deemed to constitute, or be taken into account in determining whether there has been, a material adverse effect, except to the extent such facts or circumstances are themselves excepted from the definition of material adverse effect pursuant to any other clause of the definition);



•

any action taken by either party with the other party's express written consent or any action taken by either party that such party was expressly required to take pursuant to the terms of the merger agreement;



•

any failure, in and of itself, by El Dorado or PacWest to meet internal or other estimates, predictions, projections or forecasts of revenue, net income or any other measure of financial performance (except that the facts or circumstances giving rise or contributing to the failure to meet estimates or projections may be deemed to constitute, or be taken into account in

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determining whether there has been, a material adverse effect, except to the extent such facts or circumstances are themselves excepted from the definition of material adverse effect pursuant to any other clause of the definition);

•

changes in economic conditions affecting commercial banks generally (except to the extent that such change in economic conditions disproportionately adversely affects El Dorado and its subsidiaries or PacWest and its subsidiaries, as the case may be, compared to other companies of similar size and operating in the commercial banking industry in which such party operates, in which case only the disproportionate effect will be taken into account);



•

for purposes of the conditions set forth in the merger agreement that there not be a material adverse effect on the other party since the date of the merger agreement, those matters disclosed in the PacWest disclosure schedules and El Dorado disclosure schedules, respectively, in each case, consistent with the standard set forth in the merger agreement and based on the information on those matters made available on or prior to the date of the merger agreement (except to the extent of any adverse developments with respect to such matters arising after the date of the merger agreement); or



•

changes in relationships with customers or employees of the respective parties and their respective subsidiaries that were primarily the result of the announcement or public disclosure of the merger agreement and the transactions contemplated thereby.

        The representations and warranties in the merger agreement do not survive the effective time and, as described below under the section entitled "Termination of the Merger Agreement," if the merger agreement is validly terminated, there will be no liability or damages arising under the representations and warranties of PacWest or El Dorado, or otherwise under the merger agreement, unless PacWest or El Dorado willfully and intentionally breached the merger agreement.

Conduct of Business Prior to the Completion of the Merger

        El Dorado has agreed that, prior to the effective time, except as approved in writing by PacWest, as expressly contemplated by the merger agreement or as required by law, El Dorado and its subsidiaries' respective businesses will be conducted in the ordinary and usual course and El Dorado and its subsidiaries will use its reasonable best efforts to preserve its business organizations and assets intact and maintain its rights, franchises, powers and privileges and its existing relations and goodwill with governmental authorities, customers, suppliers, distributors, creditors, lessors, employees and business associates and keep available the services of El Dorado and its subsidiaries' present employees and agents, and subject to the covenants relating to regulatory applications, as described under "Regulatory Matters" below, El Dorado and its subsidiaries will take no action that would reasonably be expected to adversely affect or materially delay El Dorado's ability to obtain any necessary approvals of any regulatory authorities or other governmental authority required for the transactions contemplated by the merger agreement or to perform their covenants and agreements under the merger agreement or to consummate the transactions contemplated by the merger agreement on a timely basis.

        In addition to the general covenants above, El Dorado has agreed that until the effective time, except as otherwise expressly required by the merger agreement or as required by law, or as PacWest may approve in writing (such approval not to be unreasonably withheld or delayed), subject to certain

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exceptions (including those set forth in El Dorado's disclosure schedules), El Dorado will not and will not permit its subsidiaries to:

Capital Stock

•

issue, sell, pledge, dispose of, encumber, permit to become outstanding or authorize the creation of any shares of capital stock or any rights;



•

permit any shares of capital stock of El Dorado or any of its subsidiaries to become subject to grants of employee or director stock options, other rights or similar stock-based employee rights;

Dividends and Stock Repurchases

•

make, declare, pay or set aside for payment of dividends payable in cash, stock or property on or in respect of, or declare or make any distribution on, any shares of its capital stock except for (i) customary quarterly cash dividends on shares of El Dorado common stock at a rate not in excess of $4.25 per share of El Dorado common stock and (ii) dividends paid by any wholly-owned subsidiary to El Dorado or to any other wholly-owned subsidiary;



•

directly or indirectly adjust, split, combine, redeem, reclassify, purchase or otherwise acquire any shares of its capital stock;

Compensation

•

enter into, renew, terminate, amend or otherwise modify any employment, retention, change in control, consulting, transition, termination, severance or similar agreements or arrangements with any director, officer, employee or independent contractor (who is a natural person) of El Dorado or any of its subsidiaries; enter into any collective bargaining or similar agreement; pay or award, or commit to pay or award, any bonus or incentive compensation, grant any salary or wage increase or increase any employee compensation or benefit (including incentive or bonus payments); or forgive any loans or issue any loans to any employee or consultant of El Dorado, except (i) for increases in annual base salary or wage rates for employees who are below the level of senior vice president in the ordinary and usual course of business consistent with past practice that do not exceed eight percent individually or four and a half percent in the aggregate, (ii) to the extent required by the terms of an existing benefit plan as in effect as of the date of the merger agreement or (iii) for other changes that are required by applicable law;



•

grant or approve the grant of any new equity-based awards;

Hiring

•

hire any person as an employee of El Dorado or any of its subsidiaries or engage any independent contractor or promote any employee, other than (i) any person hired or promoted to fill any vacancies below the level of senior vice president arising on or after the date of the merger agreement in the ordinary course of business on ordinary course terms and conditions; (ii) any person hired as an employee or any employee promoted to a position with an annual base salary or wage rate and target cash bonus opportunity of no more than $100,000 in the aggregate; and (iii) any person engaged as an independent contractor (who is a natural person) with consulting fees of no more than $50,000 per annum;



•

neither El Dorado nor any of its subsidiaries may terminate the employment of any executive officer other than for cause;

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Benefit Plans

•

enter into, terminate, establish, adopt or amend any benefit plan, any arrangement that would have been a benefit plan had it been entered into prior to the date of the merger agreement or any other employee benefit or compensation plan, program, policy or arrangement for the benefit or welfare of any current or former director, officer, employee or consultant of El Dorado or any of its subsidiaries;



•

take any action to accelerate the vesting or lapsing of restrictions under any benefit plan, other than actions required pursuant to the merger agreement;



•

fund or in any other way secure the payment of any cash benefits, in each case, except to the extent required by applicable law or the terms of an existing benefit plan as in effect as of the date of the merger agreement;

Dispositions

•

sell, transfer, lease, license, guarantee, mortgage, pledge, encumber or otherwise create any lien on, dispose of or discontinue any of its assets, deposits, business or properties (other than sales of loans and loan participations) except in the ordinary and usual course of business consistent with past practice and in a transaction that, together with all other such transactions, is not material to El Dorado and its subsidiaries, taken as a whole;

Acquisitions

•

acquire (other than by way of foreclosures or acquisitions of control in a bona fide fiduciary capacity or in satisfaction of debts previously contracted in good faith, in each case in the ordinary and usual course of business consistent with past practice) all or any portion of the assets, business, equity interests, deposits or properties of any other person (other than purchases of loans and loan participations as permitted by the terms of the merger agreement);

Mergers

•

merge or consolidate El Dorado or any of its subsidiaries with any other person, except for any such transaction among its wholly owned subsidiaries, or restructure, reorganize or completely or partially liquidate or otherwise enter into any agreements or arrangements imposing material changes or restrictions on its assets, operations or businesses;

Capital Expenditures

•

make any capital expenditures other than maintenance capital expenditures made in the ordinary course of business;

Governing Documents

•

amend either the El Dorado charter or bylaws, or the organizational documents of any of its subsidiaries;

Accounting Methods

•

implement or adopt any change in El Dorado's book or tax accounting principles, practices or methods, other than as may be required by GAAP, and as concurred by El Dorado's independent public accountants, or as required by the merger agreement;



•

except as may be required by GAAP, and in the ordinary course of business consistent with past practice, revalue in any material respect any of its assets;

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Contracts

•

except with respect to contracts relating to loans or loan participations made in the ordinary and usual course of business consistent with past practice, enter into, renew or allow to renew automatically, modify, amend or terminate, make any payment not then required under or waive, release or assign any material right or claim under, any material contract (as defined in the merger agreement) or any contract which would be a material contract if it were in existence on the date of the merger agreement in each case which is not terminable at will or with 30 calendar days or less notice without payment of any amount other than for products delivered or services performed through the date of termination;

Claims

•

enter into any settlement, compromise or similar agreement with respect to any action, suit, proceeding, order or investigation to which El Dorado or any of its subsidiaries is or becomes a party after the date of the merger agreement, involving a payment by El Dorado or any subsidiary of an amount that exceeds $75,000 individually or $250,000 in the aggregate or would impose any material restriction on the business of the surviving bank or create adverse precedent for claims that are reasonably likely to be material to El Dorado and its subsidiaries, taken as a whole;

Adverse Actions

•

take any action or omit to take any action that is intended to or would reasonably be likely to result in: (i) any of El Dorado's representations or warranties set forth in the merger agreement being or becoming untrue in any material respect at any time at or prior to the effective time; (ii) a condition to the merger not being satisfied; (iii) the merger being prevented or impeded from qualifying as a reorganization within the meaning of Section 368 of the Internal Revenue Code; or (iv) a material violation of any provision of the merger agreement, except as may be required by applicable law;

Risk Management

•

except as required by law or regulation or by the OCC: (i) implement or adopt any material change in its interest rate or other risk management policies, procedures or practices; (ii) fail to follow in all material respects El Dorado's or its applicable subsidiary's existing policies or practices with respect to managing its exposure to interest rate and other risk; or (iii) fail to use commercially reasonable efforts to avoid any material increase in El Dorado's aggregate exposure to interest rate risk;

Indebtedness

•

incur or modify any indebtedness for borrowed money or other liability (other than deposits, federal funds borrowings and borrowings from the Federal Home Loan Bank of San Francisco) or assume, guarantee, endorse or otherwise as an accommodation become responsible for the obligations of any other person;

Loans

•

forgive any loans to directors, officers or employees or make any loan that is not made in conformity with the Company's ordinary course lending policies and guidelines in effect as of the date of the merger agreement;

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•

make any loan or loan commitment to any person which would, when aggregated with all outstanding loans or loan commitments or any renewals or extensions thereof made to such person and to El Dorado's knowledge, such person's affiliates and immediate family members, exceed $1,000,000;



•

purchase or sell any loan or loan participation in excess of $1,000,000;



•

without, in the case of the second and third bullets above, first submitting a copy of the loan write up containing the information customarily submitted to the loan committee of El Dorado, to the chief credit officer of PacWest two business days prior to taking such action; provided that, if PacWest objects in writing to such action within two business days after receiving such loan write up, El Dorado will obtain the approval of a majority of the members of the loan committee of El Dorado prior to making such loan or loan commitment or such purchase or sale;

Deposits

•

increase interest rates payable or offered on any deposits in a manner that would cause the cumulative increase in such interest rates to exceed an amount equal to the sum of (i) (A) 0.10%, in the case of any deposits other than time deposits, 0.20%, in the case of time deposits with a term of less than 24 months, 0.80%, in the case of time deposits with a term equal to or greater than 24 months (provided that rates on time deposits with a term in excess of 24 months may be offered at a rate equal to the highest calculated rate for a shorter term), and (B) in each case under clause (A), the difference between the federal funds rate as of the date of the merger agreement (which was 1.92%) and the then effective federal funds rate multiplied by (ii) 35%;



•

book any "brokered deposits" or any listing service certificates of deposit;

Investments

•

other than the purchases of direct obligations of the United States of America or obligations of United States government agencies which are entitled to the full faith and credit of the United States of America in accordance with the investment policies of El Dorado or any of its subsidiaries in effect on the date of the merger agreement with a remaining maturity at the time of purchase of 24 months or less, make any investment either by contributions to capital, property transfers or purchase of any property or assets of any person or purchase or acquire securities of any type;



•

except that in the case of investment securities, El Dorado may purchase investment securities if, within two business days after El Dorado requests in writing (which request shall describe in detail the investment securities to be purchased and the price thereof) that PacWest consent to making of any such purchase, PacWest has approved such request in writing or has not responded in writing to such request;

Taxes

•

commence or settle any litigation or proceeding with respect to any liability for taxes, or take any action which is reasonably likely to have a material adverse impact on the tax position of El Dorado, or, after the merger, which is reasonably likely to have a material adverse impact on the tax position of the surviving bank;



•

except in the ordinary course of business consistent with past practice, make or change any express or deemed tax election or file any tax return;

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•

file any amended tax return;



•

change any of its methods of reporting income or deductions for tax purposes;



•

change the entity classification of El Dorado or any of its subsidiaries;



•

consent to any extension or waiver of the limitation period applicable to any material tax claim or assessment; or



•

take any other action with respect to taxes that is outside the ordinary and usual course of business or inconsistent with past practice;



•

in each case referred to in the bullet points above, except to the extent that the action is taken in response to changes enacted by the Tax Cuts and Jobs Act and the action is reasonably determined to be in the best interests of El Dorado or any of its subsidiaries;

Branches

•

apply for the opening, relocation or closing of any, or open, relocate or close any, branch office, loan production office or other significant office or operations facility of El Dorado or any of its subsidiaries;

New Business

•

enter into any new line of business or change in any material respect El Dorado's lending, investment, underwriting, risk and asset liability management and other banking and operating, securitization and servicing policies, as applicable, except as required by applicable law or policies imposed by any governmental authority;

Lending Practices

•

other than in the ordinary course of business consistent with past practice, make any material changes in El Dorado's policies and practices with respect to (i) underwriting, pricing, originating, acquiring, selling, servicing, or buying or selling rights to service loans or (ii) its hedging practices and policies, in each case except as required by law or requested by a governmental authority; or

Commitments

•

agree or commit to do any of the foregoing.

PacWest Forbearance

        PacWest has agreed as to itself and its subsidiaries that, prior to the effective time (unless El Dorado shall otherwise approve in writing, and except as otherwise expressly contemplated by the merger agreement and except as required by applicable law), it will not and will cause each of its subsidiaries not to:

Adverse Actions

•

take any action or omit to take any action that is intended to or would reasonably be likely to result in (i) any of PacWest's representations and warranties set forth in the merger agreement being or becoming untrue in any material respect at any time at or prior to the effective time; (ii) any of the conditions to the merger not being satisfied; or (iii) a material violation of any provision of the merger agreement, except as may be required by applicable law;

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Governing Documents

•

amend PacWest's certificate of incorporation or bylaws, or the organizational documents of any of its subsidiaries, in each case in a manner that would adversely affect the holders of shares of El Dorado common stock relative to and disproportionately to all other holders of PacWest common stock; or

Commitments

•

enter into any contract with respect to, or otherwise agree or commit to do, any of the foregoing.

Regulatory Matters

        PacWest and El Dorado have agreed to prepare and file this document, and PacWest has agreed to prepare and file with the SEC the registration statement on Form S-4 in connection with the issuance of shares of PacWest common stock in the merger, as promptly as practicable, of which this document is a part. Each party has agreed to use its reasonable best efforts to have the S-4 registration statement declared effective under the Securities Act as promptly as practicable after such filing.

        PacWest and El Dorado have agreed to cooperate and use their respective reasonable best efforts to prepare and file, or in the case of PacWest cause to be filed, all documentation to effect all necessary notices, reports and other filings and to obtain all permits, consents, approvals and authorizations necessary or advisable to be obtained from any third parties and/or governmental authorities in order to consummate the merger or any of the other transactions contemplated by the merger agreement.

        Nothing contained in the merger agreement will be deemed to require PacWest to take any action, or commit to take any action, or agree to any condition or restriction, in connection with obtaining the foregoing permits, consents, approvals and authorizations of governmental authorities that would reasonably be likely to be a materially burdensome regulatory condition.

Shareholder Approval

        El Dorado has agreed to convene a meeting of its shareholders as soon as practicable after the S-4 registration statement is declared effective, and will in any event use reasonable best efforts to convene such meeting no later than 50 calendar days after the S-4 registration statement is declared effective, to consider and vote upon the approval of the merger. Subject to certain limited exceptions, the El Dorado board of directors will recommend to El Dorado shareholders that they approve the merger. Unless the merger agreement is terminated in accordance with its terms, El Dorado will convene such meeting regardless of whether or not (i) the El Dorado board of directors has changed its recommendation that El Dorado shareholders approve the merger or (ii) an acquisition proposal from a third party has been made (discussed in more detail below).

Employee Matters

        For a period of one year following the effective time, PacWest will provide, or cause to be provided, to each of the employees of El Dorado and its subsidiaries as of immediately prior to the effective time who continue employment with PacWest or any of its subsidiaries following the effective time with a base salary or base wage, short-term cash bonus opportunities and pension and welfare opportunities that are substantially comparable in the aggregate to those that are generally made available to similarly situated employees of PacWest and its subsidiaries.

        PacWest has agreed to use commercially reasonable efforts to give El Dorado employees full credit for their service with El Dorado for purposes of eligibility, vesting, benefit accrual and determination of

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the level of benefits under any employee benefit plans that such employees may be eligible to participate in after the closing to the same extent recognized by El Dorado immediately prior to the closing, except to the extent it would result in the duplication of benefits for the same period of service and other than (i) for benefit accrual purposes under any defined benefit pension plan of PacWest or its subsidiaries and (ii) for purposes of qualifying for subsidized early retirement benefits.

        PacWest has agreed to use commercially reasonable efforts to (i) waive all limitations as to preexisting conditions and exclusions (to the extent such conditions were covered or satisfied under the applicable plans of El Dorado) with respect to participation and coverage requirements applicable to the El Dorado employees under any life, disability, medical, dental, vision or health plans that such employees may be eligible to participate in after the closing; (ii) provide each El Dorado employee with full credit under medical, dental and health plans for any co-payments, deductibles and out-of-pocket expenses incurred by such employees (and their beneficiaries) under analogous plans of El Dorado or any of its subsidiaries during the portion of the applicable plan year prior to such employee's participation in any medical, dental or health plans of PacWest after the closing; and (iii) waive any waiting period limitations or actively-at-work requirements previously satisfied by an El Dorado employee (or their beneficiaries, as applicable), under an analogous plan of El Dorado prior to the closing.

Indemnification and Directors' and Officers' Insurance

        Pursuant to the terms of the merger agreement, following the effective time, PacWest has agreed to, or will cause the surviving bank to, indemnify present and former directors, officers and, to the extent required by El Dorado's charter and bylaws (in each case, as in effect as of the date of the merger agreement), each employee of El Dorado (determined as of the effective time) in connection with any claim arising out of actions or omissions occurring at or prior to the effective time to the fullest extent permitted under law and under El Dorado's charter and bylaws (in each case, as in effect as of the date of the merger agreement).

        For a period of six years from the effective time, PacWest has agreed to, or cause the surviving bank to, provide, the portion of directors' and officers' liability insurance that serves to reimburse the present and former directors and officers of El Dorado on terms and conditions no less advantageous to such officers and directors than those provided by El Dorado; provided, however, that PacWest and the surviving bank are not required to spend more than 250% of the current annual amount spent by El Dorado to procure such insurance coverage. In lieu thereof, PacWest may, or may cause the surviving bank to, purchase a six-year tail policy subject to the limitation on cost described in the preceding sentence.

Acquisition Proposals

        Under the terms of the merger agreement, El Dorado has agreed that neither it nor its subsidiaries nor any of their respective officers, directors, employees and affiliates will, and that El Dorado will direct and use its reasonable best efforts to cause its and its subsidiaries' agents and representatives not to, directly or indirectly:

•

initiate, solicit, encourage or otherwise facilitate any inquiries or the making of any proposal or offer that constitutes, or would reasonably be expected to lead to an acquisition proposal; or



•

engage in any negotiations concerning, or provide any confidential information or data to, or have any discussions with any person relating to an acquisition proposal or any inquiry, offer or proposal that would reasonably be expected to lead to an acquisition proposal or otherwise facilitate any effort or attempt to make or implement an acquisition proposal.

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        For purposes of the merger agreement, "acquisition proposal" means:

•

any proposal, offer or inquiry with respect to a merger, joint venture, partnership, consolidation, dissolution, liquidation, tender offer, recapitalization, reorganization, share exchange, business combination or similar transaction involving El Dorado or any of its subsidiaries that if consummated would result in any person (or such person's shareholders) owning 15% or more of the total voting power of El Dorado or the surviving entity in a merger involving El Dorado or the resulting parent company; and



•

any proposal or offer to acquire in any manner, directly or indirectly, 15% or more of the total voting power of any class of equity securities of El Dorado or those of any of its subsidiaries or 15% or more of El Dorado's consolidated total assets.

        However, the above restriction would not prevent El Dorado or its board of directors from:

•

at any time before, but not after the El Dorado shareholder approval is obtained, providing information in response to a request therefor by a person who has made an unsolicited bona fide written acquisition proposal if El Dorado receives from the person so requesting such information, an executed confidentiality agreement on terms not less restrictive to the other party than those contained in the confidentiality agreement between PacWest and El Dorado; or



•

engaging in any negotiations or discussions with any person who has made an unsolicited bona fide written acquisition proposal;

only if, however, in each case referred to in the bullet points above, the El Dorado board of directors determines in good faith (after consultation with outside legal counsel) that (i) based on the information then available (and after consultation with its financial advisor) such acquisition proposal constitutes a superior proposal (as defined below) or would reasonably be expected to result in a superior proposal and (ii) the failure to take such action would reasonably be expected to violate the directors' fiduciary duties under applicable law.

        Further, the merger agreement provides that the El Dorado board of directors and each committee thereof will not:

•

except as expressly permitted by the merger agreement, withhold, withdraw, qualify or modify (or publicly propose or resolve to withhold, withdraw, qualify or modify), in a manner adverse to PacWest, the recommendation of its board of directors that its shareholders approve the merger; or



•

cause or permit El Dorado to enter into any letter of intent, memorandum of understanding, agreement in principle, acquisition agreement, merger agreement or other agreement (other than a confidentiality agreement enter into in compliance with the merger agreement) relating to any acquisition proposal.

        Notwithstanding the above, prior to the time the El Dorado shareholder approval is obtained, the El Dorado board of directors may withhold, withdraw or adversely modify the recommendation of its board of directors or approve, recommend or otherwise declare advisable any superior proposal (as defined below) made to El Dorado after the date of the merger agreement that was not solicited, initiated, encouraged or facilitated in breach of the merger agreement, if (i) an unsolicited bona fide written offer is made to El Dorado and is not withdrawn and the El Dorado board of directors determines in good faith (after consultation with its financial advisor) that such acquisition proposal is a superior proposal, and (ii) the El Dorado board of directors determines in good faith, after consultation with outside counsel, that the failure to take such action would result in a violation of the directors' fiduciary duties under applicable law; provided, however, that no such change of recommendation may be made until after (a) at least five business days following PacWest's receipt of notice from El Dorado advising that the El Dorado board of directors intends to take such action and

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the basis therefor and (b) El Dorado has negotiated in good faith to permit PacWest to modify the merger agreement during such five business day period. In determining whether to make a change of recommendation, the El Dorado board of directors will take into account any changes to the terms of the merger agreement proposed by PacWest and any other information provided by PacWest in response to such notice.

        As used in the merger agreement, "superior proposal" means an unsolicited bona fide acquisition proposal (provided that for purposes of the definition of "superior proposal" the references to "15%" in the definition of "acquisition proposal" will instead refer to "50%") that the El Dorado board of directors has determined in its good faith judgment is reasonably likely to be consummated in accordance with its terms, taking into account all legal, financial and regulatory aspects of the proposal and the person making the proposal, and if consummated, would result in a transaction more favorable to El Dorado shareholders from a financial point of view than the transaction contemplated by the merger agreement (after taking into account any revisions to the terms of the merger and the time likely to be required to consummate such acquisition proposal).

Conditions to Consummation of the Merger

        The respective obligation of each party to effect the merger is subject to the satisfaction or written waiver at or prior to the closing of each of the following conditions:

•

El Dorado having obtained the El Dorado shareholder approval;



•

no governmental authority of competent jurisdiction having enacted, issued, promulgated, enforced or entered any law (whether temporary, preliminary or permanent) that is in effect and restrains, enjoins or otherwise prohibits consummation of the merger or the other transactions contemplated by the merger agreement; and



•

the S-4 registration statement having become effective under the Securities Act, no stop order suspending the effectiveness of the S-4 registration statement, of which this document is a part, having been issued and remaining in effect, and no proceedings for that purpose having commenced or been threatened in writing by the SEC and remaining in effect.

        El Dorado's obligation to effect the merger is also subject to the fulfillment or waiver of the following conditions:

•

the accuracy of the representations and warranties of PacWest set forth in the merger agreement, subject to the materiality standards set forth in the merger agreement, as of the date of the merger agreement and as of the closing date of the merger as though made at and as of the closing date (except that representations and warranties that by their terms speak as of the date of the merger agreement or some other date need only be true and correct as of such date), and El Dorado's receipt of a certificate signed on behalf of PacWest by an executive officer of PacWest, dated as of the closing date, to such effect;



•

performance by PacWest in all material respects of all obligations required to be performed by it under the merger agreement at or prior to the closing, and receipt by El Dorado of a certificate signed by an executive officer of PacWest, dated as of the closing date, to such effect;



•

all consents, registrations, approvals, permits and authorizations required to be obtained prior to the effective time by either party or any of its respective subsidiaries from the FDIC and the CDBO which are necessary to consummate the merger, and any other consents, registrations, approvals, permits and authorizations from or with any governmental authority the failure of which to be obtained is reasonably likely to have, individually or in the aggregate, a material adverse effect on El Dorado or PacWest (measured on a scale relative to El Dorado), having

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been made or obtained (as the case may be) and remaining in full force and effect and all statutory waiting periods in respect thereof having expired;

•

since September 11, 2018, no event having occurred or circumstance arisen that, individually or taken together with all other facts, circumstances or events, has had or is reasonably likely to have a material adverse effect with respect to PacWest;



•

all filings required to be made with NASDAQ in respect of the issuance of PacWest common stock in the merger having been completed and made in compliance with applicable NASDAQ rules; and



•

receipt by El Dorado of an opinion of its counsel, in form and substance reasonably satisfactory to El Dorado, dated as of the date of the merger, to the effect that, on the basis of certain facts, representations and assumptions described or referred to in such opinion, for U.S. federal income tax purposes, the merger will qualify as a "reorganization" within the meaning of Section 368(a) of the Internal Revenue Code.

        PacWest's obligation to complete the merger is also subject to the satisfaction or waiver of the following conditions:

•

the accuracy of the representations and warranties of El Dorado set forth in the merger agreement, subject to the materiality standards set forth in the merger agreement, as of the date of the merger agreement and as of the closing date of the merger as though made at and as of the closing date (except that representations and warranties that by their terms speak as of the date of the merger agreement or some other date need only be true and correct as of such date), and PacWest's receipt of a certificate signed on behalf of El Dorado by an executive officer of El Dorado, dated as of the closing date, to such effect;



•

performance by El Dorado in all material respects of all obligations required to be performed by it under the merger agreement at or prior to the closing, and receipt by PacWest of a certificate signed by an executive officer of El Dorado, dated as of the closing date, to such effect;



•

all consents, registrations, approvals, permits and authorizations required to be obtained prior to the effective time by either party or any of its respective subsidiaries from the FDIC and the CDBO which are necessary to consummate the merger, and any other consents, registrations, approvals, permits and authorizations from or with any governmental authority the failure of which to be obtained is reasonably likely to have, individually or in the aggregate, a material adverse effect on El Dorado or PacWest (measured on a scale relative to El Dorado), having been made or obtained (as the case may be) and remaining in full force and effect and all statutory waiting periods in respect thereof having expired, and none of such consents, registrations, approvals, permits and authorizations containing any materially burdensome regulatory condition;



•

as of the last day of the month immediately preceding the month in which the closing date occurs, which is referred to as the measurement date (except if the closing date occurs within the first 10 days of any month, the measurement date will be the last day of the second month immediately preceding the month in which the closing date occurs), the sum of the adjusted El Dorado shareholders' equity (defined below) and allowance for loan losses not being less than $235,100,000, in each case determined in accordance with generally accepted accounting principles in the United States, referred to as GAAP; "adjusted El Dorado shareholders' equity" means the consolidated equity of El Dorado as set forth in the closing financial statements, minus any unrealized gains or plus any unrealized losses (as the case may be in accordance with GAAP) in El Dorado's securities portfolio due to mark-to-market adjustments as of the measurement date, and adding the sum of (i) the amount of any real property adjustment, (ii) all amounts paid or accrued in connection with certain actions taken to conform certain

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policies and practices to those of PacWest to the extent that such actions were not necessary to bring El Dorado into conformity with GAAP or any applicable law of any governmental authority, (iii) all fees and expenses of all attorneys, accountants, investment bankers and other advisors and agents, including the title company and environmental consultant engaged in connection with the title and environmental reviews described under "The Merger Agreement—Merger Consideration," for El Dorado for services rendered solely in connection with the transactions contemplated by the merger agreement paid by El Dorado prior to the effective time and which do not exceed in the aggregate $9,000,000 (exclusive of reasonable costs incurred or advanced by such advisors), (iv) any costs incurred in connection with complying with the requirements in the merger agreement with respect to environmental assessments and (v) any costs associated with the termination of employee benefit plans or programs (inclusive of any severance compensation paid or to be paid as provided in the merger agreement) or any retention bonuses paid in accordance with the merger agreement or otherwise approved by PacWest, and any costs incurred in connection with the termination of El Dorado's contracts pursuant to the merger agreement;

•

El Dorado's average total deposits for the calendar month immediately preceding the closing date not being less than $1.956 billion;



•

since September 11, 2018, no event having occurred or circumstance arisen that, individually or taken together with all other facts, has had or is reasonably likely to have a material adverse effect with respect to El Dorado;



•

receipt by PacWest of the opinion of its counsel, in form and substance reasonably satisfactory to PacWest, dated as of the date of the merger, to the effect that, on the basis of facts, representations and assumptions set forth or referred to in such opinion, the merger will qualify for U.S. federal income tax purposes as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code;



•

holders of not more than 10% of outstanding shares of El Dorado common stock having duly exercised their dissenters' rights under 12 C.F.R. § 5.33(g)(7)(iii) and 12 U.S.C. § 214a; and



•

all applicable time periods set forth in the merger agreement relating to the determination of the costs associated with any title defects or environmental conditions for each of El Dorado's owned real properties having expired.

Termination of the Merger Agreement

        The merger agreement may be terminated and the merger may be abandoned:

•

at any time prior to the effective time, whether before or after the El Dorado shareholder approval, by action of the board of directors of PacWest and El Dorado, in the event that both parties mutually consent in writing to terminate the merger agreement;



•

at any time prior to the effective time, whether before or after the El Dorado shareholder approval, by action of the board of directors of either party, in the event that the merger is not consummated by June 30, 2019, which date is referred to as the end date, except to the extent that the failure of the merger to be consummated results from the knowing action or inaction of the party seeking to terminate, which action or inaction is in violation of its obligations under the merger agreement;



•

at any time prior to the effective time, whether before or after the El Dorado shareholder approval, by action of the board of directors of either party if: (i) the approval of any governmental authority required for consummation of the merger or the other transactions contemplated by the merger agreement has been denied by final and nonappealable action of

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such governmental authority, or an application therefor has been permanently withdrawn by mutual agreement of the parties at the request or suggestion of a governmental authority or (ii) the El Dorado shareholder approval is not obtained at the duly convened special meeting or any adjournment or postponement thereof taken in accordance with the merger agreement;

•

at any time prior to the effective time, whether before or after the El Dorado shareholder approval, by action of the board of directors of either party if there has been a breach of any representation, warranty, covenant or agreement made by the other party, such that if continuing on the closing date of the merger, the condition as to the accuracy of the representations and warranties or the compliance with covenants by the other party would not be satisfied and such breach or condition is not curable or, if curable, is not cured within 30 calendar days after written notice thereof is given by the terminating party (or such shorter period as remaining prior to the end date); provided, that the terminating party is not then in material breach of any representation, warranty, covenant or agreement;



•

by action of PacWest's board of directors at any time prior to the El Dorado shareholder approval, in the event: (i) El Dorado has breached in any material respect the prohibitions in the merger agreement relating to acquisition proposals; (ii) the El Dorado board of directors has effected a change of recommendation; or (iii) at any time following receipt of a public acquisition proposal (other than a tender offer or exchange offer), the El Dorado board of directors has failed to reaffirm its recommendation that the El Dorado shareholders approve the merger as promptly as practicable (but in any event within five business days) after receipt of any written request to do so by PacWest (or, if earlier, by the close of business on the business day immediately preceding the special meeting);



•

at any time prior to the effective time, whether before or after the El Dorado shareholder approval, (i) by action of El Dorado's board of directors if the real property adjustment amount exceeds $15,000,000 (unless PacWest agrees that the real property adjustment amount will be $15,000,000), or (ii) by action of PacWest's board of directors if the real property adjustment amount exceeds $25,000,000; or



•

by action of El Dorado's board of directors, by written notice to PacWest on the business day immediately following the price determination date, effective as of three business days following the date of such written notice, in the event that: (i) the PacWest average closing price is less than $42.80 per share (with a proportionate adjustment for any stock dividend, reclassification, recapitalization, split-up, combination, exchange of shares or similar transaction between the date of the merger agreement and the price determination date) and (ii) the PacWest average closing price underperforms the average price of the KBW Index during the determination period by more than 15%.

If El Dorado elects to terminate the merger agreement and provides written notice thereof to PacWest, then within two business days following PacWest's receipt of such notice, PacWest may elect to reinstate the merger and related transactions, and adjust the exchange ratio to equal the lesser of (i) the quotient of $2,491.71 divided by the PacWest average closing price and (ii) the quotient of $2,491.71 divided by the PacWest average closing price, multiplied by the index ratio. Alternatively, PacWest may elect not to adjust the exchange ratio, and, in lieu thereof, may increase the cash consideration per share of El Dorado common stock such that the value of the total consideration received for each share is the same as if the exchange ratio had been adjusted as described above.

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Termination Fee

        El Dorado must pay PacWest a termination fee of $18,669,000 in the following circumstances:

•

PacWest terminates the merger agreement because (i) El Dorado has breached in any material respect the prohibitions in the merger agreement relating to acquisition proposals; (ii) the El Dorado board of directors has effected a change of recommendation; or (iii) at any time following receipt of a public acquisition proposal (other than a tender offer or exchange offer), the El Dorado board of directors has failed to reaffirm its recommendation that the El Dorado shareholders approve the merger as promptly as practicable (but in any event within five business days) after receipt of any written request to do so by PacWest (or, if earlier, by the close of business on the business day immediately preceding the special meeting); or



•

(i) (a) an acquisition proposal has been made to El Dorado or its shareholders generally or (b) any person has publicly announced an intention to make an acquisition proposal with respect to El Dorado; (ii) thereafter the merger agreement is terminated by either party because (A) the merger was not consummated on or before the end date and the El Dorado shareholder approval has not been obtained or (B) the El Dorado shareholder approval was not obtained at the special meeting and (iii) within 12 months after the termination of the merger agreement, El Dorado enters into a definitive agreement with respect to or consummates an acquisition proposal (except that for purposes of the foregoing, references to "15%" in the definition of the term "acquisition proposal" will instead refer to "50%").

Waiver and Amendment of the Merger Agreement

        Prior to the effective time, any provision of the merger agreement may be: (i) waived in whole or in part in writing by the party benefited by the provision or by both parties; or (ii) amended or modified at any time, by an agreement in writing between the parties thereto executed in the same manner as the merger agreement, except that after the El Dorado shareholder approval is obtained, the merger agreement may not be amended if it would reduce the aggregate value of the consideration to be received by El Dorado shareholders in the merger without any subsequent approval by such shareholders or be in violation of applicable law. No failure or delay by and party in exercising any right, power or privilege under the merger agreement or under applicable law shall operate as a waiver of such rights and, except as otherwise expressly provided in the merger agreement, no single or partial exercise thereof shall preclude any other or further exercise thereof or the exercise of any other right, power or privilege.

Expenses

        Except as otherwise provided in the merger agreement, all costs and expenses incurred in connection with the merger agreement, the merger and the other transactions contemplated by the merger agreement will be paid by the party incurring such expense.

Voting Agreements

        Each of the directors of El Dorado, in his capacity as a holder of any shares of common stock of El Dorado, has entered into a voting agreement with PacWest in which each such director has agreed to vote all shares of El Dorado common stock that he beneficially owns and has the power to vote in favor of the merger proposal and any other matter that is required to be approved by the shareholders of El Dorado to facilitate the transactions contemplated by the merger agreement. The directors also agreed to vote against any proposal made in opposition to the approval of the merger or in competition with the merger agreement and against any acquisition proposal. As of the close of business on the record date, El Dorado's directors beneficially owned, in the aggregate, [            ] shares

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of El Dorado common stock, allowing them to exercise approximately [            ]% of the voting power of shares of El Dorado common stock.

        In addition, each shareholder who executed a voting agreement agreed not to (i) offer for sale, sell, transfer, tender, pledge, encumber, assign or otherwise dispose of, or enter into any contract, option or other arrangement or understanding with respect to, or consent to the offer for sale, sale, transfer, tender, pledge, encumbrance, assignment or other disposition of any shares of El Dorado common stock or (ii) enter into any voting arrangement, whether by proxy, voting agreement, voting trust or otherwise, with respect to any of their shares of El Dorado common stock, and not commit or agree to take any of the foregoing actions, subject in each case to certain limited exceptions.

        The voting agreements terminate in certain circumstances, including in the event that the merger agreement is terminated in accordance with its terms.

        The foregoing description of the voting agreements is only a summary, and shareholders are urged to read the form of voting agreement attached as Appendix B to this document, which is incorporated herein by reference.

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MATERIAL U.S. FEDERAL INCOME TAX
CONSEQUENCES OF THE MERGER

        This section describes the material United States federal income tax consequences of the merger to U.S. holders (as defined below) of shares of El Dorado common stock.

        For purposes of this discussion, a U.S. holder is a beneficial owner of shares of El Dorado common stock who for United States federal income tax purposes is:

•

a citizen or resident of the United States;



•

a corporation (or an entity treated as a corporation for U.S. federal income tax purposes), created or organized in or under the laws of the United States or any state or political subdivision thereof;



•

a trust that (1) is subject to (A) the primary supervision of a court within the United States and (B) the authority of one or more United States persons to control all substantial decisions of the trust or (2) has a valid election in effect under applicable U.S. Treasury Regulations to be treated as a United States person; or



•

an estate that is subject to U.S. federal income tax on its income regardless of its source.

        If a partnership (including for this purpose any entity treated as a partnership for U.S. federal income tax purposes) holds shares of El Dorado common stock, the tax treatment of a partner in such partnership generally will depend on the status of the partner and the activities of the partnership. If you are a partner of a partnership holding shares of El Dorado common stock, you should consult your tax advisor about the tax consequences of the merger to you.

        This discussion applies only to those El Dorado shareholders who hold their shares of El Dorado common stock as a capital asset within the meaning of Section 1221 of the Internal Revenue Code, and does not address all the U.S. federal income tax consequences that may be relevant to particular U.S. holders in light of their individual circumstances or to El Dorado shareholders that are subject to special rules, such as:

•

financial institutions;



•

investors in pass-through entities;



•

insurance companies;



•

tax-exempt organizations;



•

dealers in securities or currencies;



•

traders in securities that elect to use a mark to market method of accounting;



•

persons that hold shares of El Dorado common stock as part of a straddle, hedge, constructive sale or conversion transaction;



•

regulated investment companies;



•

real estate investment trusts;



•

certain expatriates or persons that have a functional currency other than the U.S. dollar;



•

persons who are not U.S. holders; and



•

shareholders who exercise dissenters' rights.

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        In addition, the discussion does not address any alternative minimum tax or any state, local or foreign tax consequences of the merger, nor does it address any tax consequences arising under the Medicare contribution tax on net investment income or the alternative minimum tax.

        The following discussion is based on the Internal Revenue Code, its legislative history, existing and proposed regulations thereunder and published rulings and decisions, all as currently in effect as of the date hereof, and all of which are subject to change, possibly with retroactive effect. Any such change could affect the continuing validity of this discussion.

        PacWest and El Dorado have structured the merger to qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code. The obligation of PacWest to complete the merger is conditioned upon the receipt of an opinion from Sullivan & Cromwell LLP, counsel to PacWest, to the effect that the merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code. The obligation of El Dorado to complete the merger is conditioned upon the receipt of an opinion from Manatt, Phelps & Phillips, LLP, counsel to El Dorado, to the effect that the merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code. These opinions will be based on assumptions, representations, warranties and covenants, including those contained in the merger agreement and in tax representation letters provided by PacWest and El Dorado. The accuracy of such assumptions, representations and warranties, and compliance with such covenants, could affect the conclusions set forth in such opinions. None of these opinions is binding on the Internal Revenue Service or the courts. PacWest and El Dorado have not requested and do not intend to request any ruling from the Internal Revenue Service as to the U.S. federal income tax consequences of the merger. Accordingly, each El Dorado shareholder should consult its tax advisor with respect to the particular tax consequences of the merger to such holder.

Tax Consequences of the Merger Generally to Holders of Shares of El Dorado Common Stock

        The merger is intended to qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code. In such case:

•

An El Dorado holder who receives PacWest common stock and cash (other than cash received in lieu of a fractional share of PacWest common stock) in exchange for shares of El Dorado common stock pursuant to the merger, will generally recognize gain (but not loss) in an amount equal to the lesser of (1) the amount of gain realized (i.e., the excess of the sum of the amount of cash and the fair market value of the PacWest common stock received pursuant to the merger over such holder's adjusted tax basis in the shares of El Dorado common stock surrendered in the exchange) and (2) the amount of cash received pursuant to the merger (excluding any cash received in lieu of a fractional share of PacWest common stock);



•

The aggregate tax basis in the PacWest common stock received by a holder of shares of El Dorado common stock in the merger, including any fractional share interests deemed received and redeemed (as described below), will equal such holder's aggregate adjusted tax basis in the shares of El Dorado common stock surrendered in the exchange, reduced by the amount of cash received (excluding any cash received in lieu of a fractional share) and increased by the amount of gain, if any, recognized by such holder (excluding any gain recognized with respect to cash received in lieu of a fractional share) on the exchange; and



•

the holding period of PacWest common stock received in exchange for shares of El Dorado common stock will include the holding period of the shares of El Dorado common stock for which it is exchanged.

        If U.S. holders of shares of El Dorado common stock acquired different blocks of shares of El Dorado common stock at different times or at different prices, such holders' basis and holding period

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may be determined with reference to each block of shares of El Dorado common stock. Any such holders should consult their tax advisors regarding the manner in which PacWest common stock received in the exchange should be allocated among different blocks of shares of El Dorado common stock and with respect to identifying the bases or holding periods of the particular shares of PacWest common stock received in the merger.

Cash Received In Lieu of a Fractional Share of PacWest Common Stock

        An El Dorado shareholder who receives cash in lieu of a fractional share of PacWest common stock will be treated as having received the fractional share pursuant to the merger and then as having exchanged the fractional share for cash in a redemption by PacWest. As a result, an El Dorado shareholder will generally recognize gain or loss equal to the difference between the amount of cash received and the basis in his or her fractional share interest as set forth above. This gain or loss will generally be capital gain or loss, and will be long-term capital gain or loss if, as of the effective date of the merger, the holding period for such shares is greater than one year. The deductibility of capital losses is subject to limitations.

        The preceding discussion is intended only as a summary of material United States federal income tax consequences of the merger. It is not a complete analysis or discussion of all potential tax effects that may be important to you. Thus, you are strongly encouraged to consult your tax advisor as to the specific tax consequences resulting from the merger, including tax return reporting requirements, the applicability and effect of federal, state, local, and other tax laws and the effect of any proposed changes in the tax laws.

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COMPARISON OF SHAREHOLDERS' RIGHTS

General

        El Dorado is a federal savings association chartered under the laws of the United States, and the rights of El Dorado shareholders are governed by federal law, El Dorado's charter and El Dorado's bylaws. As a result of the merger, El Dorado shareholders will receive shares of PacWest common stock and will become PacWest stockholders. PacWest is incorporated under the laws of the State of Delaware, and the rights of PacWest stockholders are governed by the laws of the State of Delaware, PacWest's certificate of incorporation and PacWest's bylaws. Thus, following the merger, the rights of El Dorado shareholders who become PacWest stockholders in the merger will no longer be governed by federal law and El Dorado's charter and bylaws and instead will be governed by the laws of the State of Delaware and PacWest's certificate of incorporation and bylaws.

Comparison of Shareholders' Rights

        Set forth below is a summary comparison of material differences between the rights of El Dorado shareholders under federal law and El Dorado's charter and bylaws (left column) and the rights of PacWest stockholders under Delaware law and PacWest's certificate of incorporation and bylaws (right column). While the parties believe that the summary table includes the material differences between the rights of El Dorado's shareholders and those of PacWest's stockholders, this summary does not include a complete description of all the differences between the rights of the stockholders. Copies of the full text of PacWest's certificate of incorporation and bylaws currently in effect are available, without charge, by following the instructions in the section entitled "Where You Can Find More Information."

 

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