SEC Form 3
FORM 3 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
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.

(Last) (First) (Middle)
1133 CONNECTICUT AVE., NW, STE 700

(Street)
WASHINGTON DC 20036

(City) (State) (Zip)
2. Date of Event Requiring Statement (Month/Day/Year)
07/25/2012
3. Issuer Name and Ticker or Trading Symbol
Northern Tier Energy LP [ NTI ]
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
X Director X 10% Owner
Officer (give title below) Other (specify below)
5. If Amendment, Date of Original Filed (Month/Day/Year)
07/25/2012
6. Individual or Joint/Group Filing (Check Applicable Line)
Form filed by One Reporting Person
X Form filed by More than One Reporting Person
Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Units 54,844,500 (1) I See footnote (2)
Table II - Derivative Securities Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4) 2. Date Exercisable and Expiration Date (Month/Day/Year) 3. Title and Amount of Securities Underlying Derivative Security (Instr. 4) 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 6. Nature of Indirect Beneficial Ownership (Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
1. Name and Address of Reporting Person*
ACON Refining Partners, L.L.C.

(Last) (First) (Middle)
1133 CONNECTICUT AVE., NW, STE 700

(Street)
WASHINGTON DC 20036

(City) (State) (Zip)
1. Name and Address of Reporting Person*
AIP V GenPar, L.L.C.

(Last) (First) (Middle)
C/O ACON FUNDS MANAGEMENT, L.L.C.
1133 CONNECTICUT AVE., NW, STE 700

(Street)
WASHINGTON DC 20036

(City) (State) (Zip)
1. Name and Address of Reporting Person*
ACON Funds Management, L.L.C.

(Last) (First) (Middle)
1133 CONNECTICUT AVE., NW, STE 700

(Street)
WASHINGTON DC 20036

(City) (State) (Zip)
Explanation of Responses:
1. This amendment is filed to correct the number of Common Units reported in Table I, which in the original Form 3 inadvertently included the 2,437,500 Common Units Right which also were reported in Table II.
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:
ACON Funds Management, L.L.C, By: Barry E. Johnson, Title: Authorized Signatory 08/02/2012
ACON Refining Partners, L.L.C., By: Barry E. Johnson, Title: Authorized Signatory 08/02/2012
AIP V GenPar, L.L.C., By: Barry E. Johnson, Title: Authorized Signatory 08/02/2012
** Signature of Reporting Person Date
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 5 (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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