UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 3)*
REPLIGEN CORPORATION
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(Name of Issuer)
COMMON STOCK, $0.01 PAR VALUE PER SHARE
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(Title of Class of Securities)
759916109
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(CUSIP Number)
December 31, 2007
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(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule
13G is filed:
[ ] Rule 13d-1(b)
[X] Rule 13d-1(c)
[ ] Rule 13d-1(d)
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).
CUSIP No. 759916109
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(1) Names of Reporting Persons. I.R.S. Identification Nos. of Above Persons
(entities only):
Xmark Opportunity Partners, LLC
20-2052197
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(2) Check the Appropriate Box if a Member of a Group (See Instructions)
(a)
(b)
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(3) SEC Use Only
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(4) Citizenship or Place of Organization: Delaware, United States
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Number of Shares Beneficially Owned
by Each Reporting Person With (5) Sole Voting Power: 0**
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(6) Shared Voting Power: 0**
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(7) Sole Dispositive Power: 0**
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(8) Shared Dispositive Power: 0**
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(9) Aggregate Amount Beneficially Owned by Each Reporting Person:
0**
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(10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
Instructions):
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(11) Percent of Class Represented by Amount in Row (9): 0%**
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(12) Type of Reporting Person (See Instructions): IA
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** Xmark Opportunity Partners, LLC ("Opportunity Partners") is the sole member
of the investment manager of Xmark Opportunity Fund, L.P., a Delaware limited
partnership ("Opportunity LP"), and Xmark Opportunity Fund, Ltd., a Cayman
Islands exempted company ("Opportunity Ltd"), and, as such, possessed sole power
to vote and direct the disposition of all securities of Repligen Corporation, a
Delaware corporation (the "Company"), held by Opportunity LP and Opportunity
Ltd. Opportunity Partners is the investment manager of Xmark JV Investment
Partners, LLC, a Delaware limited liability company ("JV Partners"), and, as
such, possessed sole power to vote and direct the disposition of all securities
of the Company held by JV Partners. David C. Cavalier and Mitchell D. Kaye, the
Chief Operating Officer and Chief Executive Officer, respectively, of Xmark
Capital Partners, LLC, the Managing Member of Opportunity Partners, share voting
and investment power with respect to all securities beneficially owned by
Opportunity Partners. As of December 31, 2007, for purposes of Reg. Section
240.13d-3, Opportunity LP, Opportunity Ltd and JV Partners held no securities of
the Company.
Item 1(a). Name Of Issuer: Repligen Corporation
Item 1(b). Address of Issuer's Principal Executive Offices:
41 Seyon Street, Building #1, Suite 100
Waltham, MA 02453
Item 2(a). Name of Person Filing:
Xmark Opportunity Partners, LLC
Item 2(b). Address of Principal Business Office or, if None, Residence:
90 Grove Street, Suite 201
Ridgefield, CT 06877
Item 2(c). Citizenship:
Xmark Opportunity Partners, LLC is a Delaware limited liability
company.
Item 2(d). Title of Class of Securities: Common Stock, $0.01 par value
per share
Item 2(e). CUSIP No.: 759916109
Item 3. If This Statement Is Filed Pursuant to Sections 240.13d-1(b) or
240.13d-2(b) or (c), check whether the Person Filing is a:
Not Applicable.
Item 4. Ownership
(a) Amount Beneficially Owned:
0**
(b) Percent of Class:
0%**
(c) Number of Shares as to which the person has:
(i) sole power to vote or to direct the vote 0**
(ii) shared power to vote or to direct the vote 0**
(iii) sole power to dispose or to direct the
disposition of 0**
(iv) shared power to dispose or to direct the
disposition of 0**
Item 5. Ownership of Five Percent or Less of a Class
If this statement is being filed to report the fact that as of the
date hereof the reporting person has ceased to be the owner of more than five
percent of the class of securities, check the following: [X]
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** Xmark Opportunity Partners, LLC ("Opportunity Partners") is the sole member
of the investment manager of Xmark Opportunity Fund, L.P., a Delaware limited
partnership ("Opportunity LP"), and Xmark Opportunity Fund, Ltd., a Cayman
Islands exempted company ("Opportunity Ltd"), and, as such, possessed sole power
to vote and direct the disposition of all securities of Repligen Corporation, a
Delaware corporation (the "Company"), held by Opportunity LP and Opportunity
Ltd. Opportunity Partners is the investment manager of Xmark JV Investment
Partners, LLC, a Delaware limited liability company ("JV Partners"), and, as
such, possessed sole power to vote and direct the disposition of all securities
of the Company held by JV Partners. David C. Cavalier and Mitchell D. Kaye, the
Chief Operating Officer and Chief Executive Officer, respectively, of Xmark
Capital Partners, LLC, the Managing Member of Opportunity Partners, share voting
and investment power with respect to all securities beneficially owned by
Opportunity Partners. As of December 31, 2007, for purposes of Reg. Section
240.13d-3, Opportunity LP, Opportunity Ltd and JV Partners held no securities of
the Company.
Item 6. Ownership of More Than Five Percent on Behalf of Another Person
Not Applicable.
Item 7. Identification and Classification of the Subsidiary Which Acquired
the Security Being Reported on by the Parent Holding Company or Control
Person
Not Applicable.
Item 8. Identification and Classification of Members of the Group
Not Applicable.
Item 9. Notice of Dissolution of Group
Not Applicable.
Item 10. Certification
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were not acquired and are not held for
the purpose of or with the effect of changing or influencing the control of the
issuer of the securities and were not acquired and are not held in connection
with or as a participant in any transaction having that purpose or effect.
SIGNATURE
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After reasonable inquiry and to the best of my knowledge and belief,
I certify that the information set forth in this statement is true, complete and
correct.
February 13, 2008
XMARK OPPORTUNITY PARTNERS, LLC
By: XMARK CAPITAL PARTNERS, LLC,
its Managing Member
By: /s/ Mitchell D. Kaye
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Name: Mitchell D. Kaye
Title: Chief Executive Officer
Attention: Intentional misstatements or omissions of fact constitute
Federal criminal violations (See 18 U.S.C. 1001)