[Form 4] MPLX LP Insider Trading Activity

Rhea-AI Filing Summary

Insider acquisition recorded: On 08/25/2025 Ray N. Walker Jr., a director of MPLX GP LLC (the general partner of MPLX LP), was reported acquiring 1,677.632 common units of MPLX at a stated price of $0. Following the transaction, he beneficially owns 1,677.632 units. The filing is signed by an attorney-in-fact on behalf of Mr. Walker.

Positive

• Director acquisition disclosed — Ray N. Walker Jr. acquired 1,677.632 common units, aligning management interests with unitholders

Negative

• None.

Insights

Financial Analyst

TL;DR: Director received a grant of 1,677.632 MPLX units at no cash cost, a small insider acquisition that is informational but not materially market-moving.

The filing shows a non-derivative acquisition coded A for 1,677.632 common units at a price of $0, suggesting a grant or distribution rather than an open-market purchase. The absolute size is small relative to typical LP public float, so immediate valuation or liquidity impact is negligible. Disclosure clarifies the reporting person is a director of the general partner, aligning governance and unit ownership.

Corporate Governance Expert

TL;DR: Director ownership alignment indicated by unit grant; routine governance disclosure with limited investor impact.

The report identifies Ray N. Walker Jr. as a director of MPLX GP LLC and reports a direct beneficial holding of 1,677.632 units acquired on 08/25/2025 at a stated price of $0. This appears to be standard director compensation or internal allocation. The filing is complete with signature via attorney-in-fact, and no derivative positions or dispositions are reported. Materiality for investors is low.

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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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).

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^*

Walker Ray N JR

(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)
08/25/2025

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)	08/25/2025		A		1,677.632	A	$0	1,677.632	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 Ray N. Walker Jr.	08/27/2025
	** 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 did Ray N. Walker Jr. report on the MPLX (MPLX) Form 4?

The Form 4 reports an acquisition on 08/25/2025 of 1,677.632 common units at a stated price of $0, leaving total beneficial ownership at 1,677.632 units.

Does the Form 4 show any dispositions or derivative transactions for MPLX?

No. The filing lists only a non-derivative acquisition and shows no derivative securities or dispositions.

What is the reporting person's relationship to MPLX in this filing?

The reporting person, Ray N. Walker Jr., is listed as a Director of MPLX GP LLC, the general partner that manages the issuer.

Was the Form 4 signed and when was it filed?

The form includes a signature by an attorney-in-fact, Molly R. Benson, dated 08/27/2025.

Does the $0 price indicate an open-market purchase?

The filing states a price of $0, which is consistent with a grant or internal allocation; the document does not describe an open-market purchase.