SEC Form 4

FORM 4		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 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Marathon Petroleum Corp (Last) (First) (Middle) 539 S. MAIN STREET (Street) FINDLAY OH 45840 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol MPLX LP [ MPLX ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 02/01/2018
	4. If Amendment, Date of Original Filed (Month/Day/Year)	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 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 Units (Limited Partner Interests)	02/01/2018		A		386,611,111(1)(2)(3)	A	(2)(3)	504,701,934	I	See Footnotes(1)(2)(3)

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 Securities Underlying Derivative Security (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: 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

1. Name and Address of Reporting Person* Marathon Petroleum Corp (Last) (First) (Middle) 539 S. MAIN STREET (Street) FINDLAY OH 45840 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* MPC Investment LLC (Last) (First) (Middle) 539 S. MAIN STREET (Street) FINDLAY OH 45840 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* MPLX GP LLC (Last) (First) (Middle) 200 E. HARDIN STREET (Street) FINDLAY OH 45840 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* MPLX Logistics Holdings LLC (Last) (First) (Middle) 200 E. HARDIN STREET (Street) FINDLAY OH 45840 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* MPLX Holdings Inc. (Last) (First) (Middle) 539 S. MAIN ST. (Street) FINDLAY OH 45840 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. This Form 4 is filed jointly by Marathon Petroleum Corporation ("MPC"), MPC Investment LLC ("MPCI"), MPLX GP LLC (the "GP"), MPLX Logistics Holdings LLC ("Logistics") and MPLX Holdings Inc. ("Holdings"). MPCI, a direct wholly owned subsidiary of MPC, owns all of the membership interests in both the GP and Logistics and all the shares of stock of Holdings. Accordingly, the GP, Logistics and Holdings are all indirect wholly owned subsidiaries of MPC.

2. Pursuant to the Membership Interests Contribution Agreement dated November 13, 2017 among the Issuer, Logistics, Holdings, the GP and MPCI, on 2/1/2018, MPCI contributed: the membership interests in MPLX Refining Logistics LLC, which owns all of the membership interests in each of Canton Refining Logistics LLC, Catlettsburg Refining Logistics LLC, Detroit Refining Logistics LLC, Galveston Bay Refining Logistics LLC, Garyville Refining Logistics LLC and Robinson Refining Logistics LLC; and all of the membership interests in MPLX Fuels Distribution LLC, to the Issuer for $4.1 billion in cash consideration and equity consideration, consisting of (i) 85,610,278 common units issued to the GP, (ii) 18,176,666 common units issued to Logistics, (iii) 7,824,167 common units issued to Holdings and (iv) 2,277,778 general partner units issued to the GP.

3. Pursuant to the Partnership Interests Restructuring Agreement dated December 15, 2017, between the Issuer and the GP, on 2/1/2018, the GP converted its 10,586,691 general partner units, representing its 2% general partner interest in the Issuer, into a non-economic general partner interest in the Issuer and the GP's general partner units and incentive distribution rights were cancelled and redeemed, in exchange for 275,000,000 newly issued common units issued to the GP.

Remarks:

	/s/ Molly R. Benson, Vice President, Corporate Secretary and Chief Compliance Officer, Marathon Petroleum Corporation	02/05/2018
	/s/ Molly R. Benson, Vice President, Corporate Secretary and Chief Compliance Officer, MPC Investment LLC	02/05/2018
	/s/ Molly R. Benson, Vice President, Corporate Secretary and Chief Compliance Officer, MPLX GP LLC	02/05/2018
	/s/ Molly R. Benson, Assistant Secretary, MPLX Logistics Holdings LLC	02/05/2018
	/s/ Molly R. Benson, Director and Secretary, MPLX Holdings Inc.	02/05/2018
	** Signature of Reporting Person	Date
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