Mannen Maryann T. - 01 Mar 2026 Form 4 Insider Report for MPLX LP (MPLX)

Reporting relationship: Chairman, President & CEO, Director
Issuer ticker: MPLX
Reported as of: 01 Mar 2026
Net transaction value: -$782,888
SEC form: 4
Accepted by SEC: 03 Mar 2026, 19:34:47 UTC
Prior SEC filing: 03 Mar 2026
Next SEC filing: 13 Apr 2026
Source filing: View source filing
Reporting owner signature: /s/ Molly R. Benson, Attorney-in-Fact for Maryann T. Mannen

Key filing fact

Mannen Maryann T. filed Form 4 for MPLX LP (MPLX) on 03 Mar 2026.

Key facts

This page summarizes Mannen Maryann T.'s Form 4 filing for MPLX LP (MPLX).
4 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 03 Mar 2026, 19:34.

Change

Previous filing in this sequence was filed on 03 Mar 2026.
Current net transaction value: -$782,888.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001408964 Primary reporting owner

Mannen Maryann T.

Relationship: Chairman, President & CEO, Director
Address: C/O MPLX LP, 200 E. HARDIN STREET, FINDLAY
Signature: /s/ Molly R. Benson, Attorney-in-Fact for Maryann T. Mannen
Signature date: 03 Mar 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

MPLX transaction

Common Units (Limited Partner Interests)

Award

Transaction value: $0
Shares: +52,817
Change %: +42%
Price: $0.000000
Shares after: 178,679
Date: 01 Mar 2026
Ownership: Direct

MPLX transaction

Common Units (Limited Partner Interests)

Tax liability

Transaction value: $201,763
Shares: -3,407
Change %: -1.9%
Price: $59.22
Shares after: 175,272
Date: 02 Mar 2026
Ownership: Direct

MPLX transaction

Common Units (Limited Partner Interests)

Tax liability

Transaction value: $201,585
Shares: -3,404
Change %: -1.9%
Price: $59.22
Shares after: 171,868
Date: 02 Mar 2026
Ownership: Direct

MPLX transaction

Common Units (Limited Partner Interests)

Tax liability

Transaction value: $379,541
Shares: -6,409
Change %: -3.7%
Price: $59.22
Shares after: 165,459
Date: 02 Mar 2026
Ownership: Direct

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

SEC remarks

The Reporting Person is a Chairman of the Board, President and Chief Executive Officer of MPLX GP LLC, the general partner of the Issuer. The Issuer is managed by the directors and executive officers of MPLX GP LLC.