Sec Form 4 Filing - ACON Refining Partners, L.L.C. @ Northern Tier Energy LP - 2013-02-08

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 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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1. Name and Address of Reporting Person ACON Refining Partners, L.L.C. 2. Issuer Name and Ticker or Trading Symbol Northern Tier Energy LP [ NTI] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director X __ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 1133 CONNECTICUT AVE., NW, STE 700, 3. Date of Earliest Transaction (MM/DD/YY) 02/08/2013 (Street) WASHINGTON, DC20036 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) _____ Form filed by One Reporting Person __ X __ 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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 Units 02/08/2013 S 1,605,000 D $ 23.4205 ( 1 ) 60,922,500 I See footnote ( 2 )

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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 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

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other ACON Refining Partners, L.L.C. 1133 CONNECTICUT AVE., NW, STE 700 WASHINGTON, DC20036 X X ACON Funds Management, L.L.C. 1133 CONNECTICUT AVE., NW, STE 700 WASHINGTON, DC20036 X X AIP V GenPar, L.L.C. C/O ACON FUNDS MANAGEMENT, L.L.C. 1133 CONNECTICUT AVE., NW, STE 700 WASHINGTON, DC20036 X X Signatures /s/ Barry E. Johnson ACON Funds Management, L.L.C., By: Barry E. Johnson, Title: Authorized Signatory 02/08/2013 Signature of Reporting Person Date /s/ Barry E. Johnson ACON Refining Partners, L.L.C., By: Barry E. Johnson, Title: Authorized Signatory 02/08/2013 Signature of Reporting Person Date /s/ Barry E. Johnson AIP V GenPar, L.L.C., By: Barry E. Johnson, Title: Authorized Signatory 02/08/2013 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The price represents the public offering price of $24.46 per common unit ("Common Unit") of Northern Tier Energy LP (the "Issuer") less the underwriters' discount of $1.03955 per Common Unit. ( 2 )The securities reported in this statement are held by Northern Tier Holdings LLC ("Holdings"). Northern Tier Investors, LLC ("Investors LLC") is the sole owner of the common interests in Holdings. The sole member of Investors LLC is Northern Tier Investors LP ("Investors LP"). The general partner of Investors LP is NTI GenPar LLC. ACON Refining Partners, L.L.C. ("Refining") owns 48.75% of the Class A common units in Investors LP and 50% of the limited liability company interests in NTI GenPar LLC. AIP V GenPar, L.L.C. ("GenPar") is the managing member of Refining. ACON Funds Management, L.L.C. ("Management") is the managing member of GenPar.

Remarks: Remarks:The Reporting Persons are jointly filing this Form 4 pursuant to Rule 16a-3(j) under the Exchange Act.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* 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).

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