[Form 4] MPLX LP Insider Trading Activity

Rhea-AI Filing Summary

John P. Surma, reported as a director of MPLX GP LLC (the general partner of MPLX LP), executed a transaction on 08/15/2025 acquiring 1,475.301 common units (limited partner interests). The form reports a price of $0 for the transaction and shows 86,095.058 common units beneficially owned following the reported transaction. The filing was signed by an attorney-in-fact, Molly R. Benson, on 08/19/2025.

Positive

• Acquisition recorded: Director John P. Surma acquired 1,475.301 common units on 08/15/2025.
• Updated ownership disclosed: Beneficial ownership increased to 86,095.058 common units following the transaction.
• Relationship clarified: Reporting person identified as a director of MPLX GP LLC, the general partner that manages the issuer.

Negative

• None.

Insights

Financial Analyst

TL;DR: Insider acquired 1,475.301 MPLX common units, modestly increasing reported beneficial ownership to 86,095.058 units.

This Form 4 documents a non-derivative acquisition by a company director on 08/15/2025. The reported price is listed as $0 and the filing shows the director's total reported beneficial ownership after the trade. As a standalone disclosure, the filing provides a clear record of the insider's transaction and resulting holdings but contains no revenue, earnings, or valuation metrics.

Corporate Governance Expert

TL;DR: Routine insider reporting by a director; shows ownership change and confirms governance linkage to the general partner.

The report identifies the reporting person as a director of MPLX GP LLC, the general partner that manages the issuer. The filing clarifies the reporting person's relationship to the issuer and records the acquisition and updated beneficial ownership. The disclosure fulfills Section 16 reporting requirements and contains no additional governance actions or changes in role.

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
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

SURMA JOHN P

(Last) (First) (Middle)

C/O MPLX LP

200 E. HARDIN 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		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
08/15/2025

4. If Amendment, Date of 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

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)	08/15/2025		A		1,475.301	A	$0	86,095.058	D

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

Explanation of Responses:

Remarks:

The Reporting Person is a Director of MPLX GP LLC, the general partner of the Issuer. The Issuer is managed by the directors and executive officers of MPLX GP LLC.

	/s/ Molly R. Benson, Attorney-in-Fact for John P. Surma	08/19/2025
	** 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 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What transaction did John P. Surma report on Form 4 for MPLX?

The Form 4 reports an acquisition of 1,475.301 common units on 08/15/2025.

How many MPLX units did John P. Surma beneficially own after the reported transaction?

The filing shows 86,095.058 common units beneficially owned following the transaction.

What price was reported for the units acquired by John P. Surma?

The transaction is reported with a price of $0 on the Form 4.

What is John P. Surma’s relationship to MPLX as stated in the filing?

He is reported as a director of MPLX GP LLC, the general partner of the issuer.

When was the Form 4 signed and by whom?

The filing was signed by Molly R. Benson, Attorney-in-Fact on 08/19/2025.