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 *
Nathenson Michael
  2. Issuer Name and Ticker or Trading Symbol
Blue Buffalo Pet Products, Inc. [BUFF]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
EVP, CFO and Treasurer
(Last)
(First)
(Middle)
C/O BLUE BUFFALO PET PRODUCTS, INC., 11 RIVER ROAD
3. Date of Earliest Transaction (Month/Day/Year)
04/24/2018
(Street)

WILTON, CT 06897
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 04/24/2018   D(1)   53,571 D (2) 0 D  

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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
Restricted Stock Units (3) 04/24/2018   D(1)     5,467   (4)   (4) Common Stock 5,467 (5) 0 D  
Restricted Stock Units (3) 04/24/2018   D(1)     4,994   (6)   (6) Common Stock 4,994 (5) 0 D  
Stock Option (Right to Buy) $ 25.57 04/24/2018   D(1)     36,207   (7) 04/01/2026 Common Stock 36,207 (8) 0 D  
Stock Option (Right to Buy) $ 23 04/24/2018   D(1)     33,318   (9) 03/31/2027 Common Stock 33,318 (8) 0 D  
Stock Option (Right to Buy) $ 5.6 04/24/2018   D(1)     436,191   (10) 12/18/2022 Common Stock 436,191 (8) 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Nathenson Michael
C/O BLUE BUFFALO PET PRODUCTS, INC.
11 RIVER ROAD
WILTON, CT 06897
      EVP, CFO and Treasurer  

Signatures

 /s/ Karen M. McCarthy, as Attorney-in-Fact   04/24/2018
**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) On April 24, 2018, General Mills, Inc., a Delaware corporation ("Buyer"), acquired the Issuer pursuant to that certain Agreement and Plan of Merger entered into by and among the Issuer, Buyer and Bravo Merger Corp., a Delaware corporation and wholly-owned subsidiary of Buyer ("Merger Sub"), dated as of February 22, 2018 (the "Merger Agreement"). In accordance with the Merger Agreement, Merger Sub merged with and into the Issuer, with the Issuer surviving such merger as a wholly-owned subsidiary of Buyer (the "Merger").
(2) At the effective time of the Merger (the "Effective Time"), each outstanding share of the Issuer's common stock (other than certain excluded shares) automatically converted into the right to receive $40.00 in cash, without interest and after giving effect to any required withholding taxes (the "Merger Consideration").
(3) Each restricted stock unit ("RSU") represents a contingent right to receive one share of Issuer common stock.
(4) These RSUs were to vest on April 1, 2019.
(5) Each RSU, whether vested or unvested, outstanding immediately prior to the Effective Time was cancelled and entitled the holder of such RSU to receive, without interest, an amount in cash equal to the product of (i) the total number of shares of Issuer common stock subject to the RSU multiplied by (ii) the Merger Consideration, less applicable tax withholding.
(6) These RSUs were to vest on March 31, 2020.
(7) These options were to vest on April 1, 2019.
(8) At the Effective Time, each stock option, whether vested or unvested, outstanding immediately before the Effective Time was cancelled and entitled the holder of such option to receive, without interest, an amount in cash equal to the product of (i) the total number of shares of Issuer common stock subject to the stock option multiplied by (ii) the excess, if any, of the Merger Consideration over the exercise price of such stock option, less applicable tax withholding.
(9) These options were to vest on March 31, 2020.
(10) Reflects an initial option grant with respect to 803,300 shares vested in five equal annual installments beginning on December 18, 2013.

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