Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
MCCAUGHAN JAMES P
  2. Issuer Name and Ticker or Trading Symbol
PRINCIPAL FINANCIAL GROUP INC [PFG]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President - Global Asset Mgmt.
(Last)
(First)
(Middle)
711 HIGH STREET
3. Date of Earliest Transaction (Month/Day/Year)
09/05/2017
(Street)

DES MOINES, IA 50392
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 09/05/2017   M(1)   15,146 A $ 60.1 210,965 (2) D  
Common Stock 09/05/2017   S(1)   15,146 D $ 62.1 (3) 195,819 (2) D  
Common Stock 09/05/2017   M(1)   3,888 A $ 11.07 199,707 (2) D  
Common Stock 09/05/2017   S(1)   3,888 D $ 62.1 (3) 195,819 (2) D  
Common Stock 09/05/2017   M(1)   9,841 A $ 22.21 205,660 (2) D  
Common Stock 09/05/2017   S(1)   9,841 D $ 62.1 (3) 195,819 (2) D  
Common Stock 09/05/2017   M(1)   12,589 A $ 34.26 208,407 (2) D  
Common Stock 09/05/2017   S(1)   12,589 D $ 62.1 (3) 195,819 (2) D  
Common Stock 09/05/2017   M(1)   19,350 A $ 27.46 215,169 (2) D  
Common Stock 09/05/2017   S(1)   19,350 D $ 62.1 (3) 195,819 (2) D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (Right to Buy) $ 60.1 09/05/2017   M(1)     15,146 02/26/2011 02/26/2018 Common Stock 15,146 $ 0 0 D  
Employee Stock Option (Right to Buy) $ 11.07 09/05/2017   M(1)     3,888 02/24/2012 02/24/2019 Common Stock 3,888 $ 0 0 D  
Employee Stock Option (Right to Buy) $ 22.21 09/05/2017   M(1)     9,841 02/23/2013 02/23/2020 Common Stock 9,841 $ 0 0 D  
Employee Stock Option (Right to Buy) $ 34.26 09/05/2017   M(1)     12,589 02/28/2014 02/28/2021 Common Stock 12,589 $ 0 0 D  
Employee Stock Option (Right to Buy) $ 27.46 09/05/2017   M(1)     19,350 02/27/2015 02/27/2022 Common Stock 19,350 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MCCAUGHAN JAMES P
711 HIGH STREET
DES MOINES, IA 50392
      President - Global Asset Mgmt.  

Signatures

 Patrick A. Kirchner, by Power of Attorney   09/06/2017
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 5, 2017.
(2) Includes 10,273 shares acquired pursuant to the Principal Financial Group, Inc. Employee Stock Purchase Plan.
(3) The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $61.58 - $62.89, inclusive. The reporting person undertakes to provide to Principal Financial Group, Inc., any security holder of Principal Financial Group, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.

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