Marathon Petroleum Corp

4. Master Limited Partnership

We own the general partner and a majority limited partner interest in MPLX, which owns and operates crude oil and light product transportation and logistics infrastructure as well as gathering, processing and fractionation assets. We control MPLX through our ownership of the general partner interest and, as of December 31, 2025, we owned approximately 64 percent of the outstanding MPLX common units.

Unit Repurchase Program

On August 5, 2025, MPLX announced its board of directors approved a $1.0 billion unit repurchase authorization in addition to the $1.0 billion unit repurchase authorization announced on August 2, 2022. These unit repurchase authorizations have no expiration date. MPLX may utilize various methods to effect the repurchases, which could include open market repurchases, negotiated block transactions, accelerated unit repurchases, tender offers or open market solicitations for units, some of which may be effected through Rule 10b5-1 plans. The timing and amount of future repurchases, if any, will depend upon several factors, including market and business conditions, and such repurchases may be suspended, discontinued or restarted at any time.

Total unit repurchases were as follows for the respective periods:

As of December 31, 2025, MPLX had approximately $1.12 billion remaining under its unit repurchase authorizations.

Series A Preferred Units

The Series A preferred units are considered redeemable securities under GAAP due to the existence of redemption provisions upon a deemed liquidation event, which is outside MPLX’s control. Therefore, they are presented as temporary equity in the mezzanine section of our consolidated balance sheets.

During the years ended December 31, 2024 and December 31, 2023, certain Series A preferred unitholders exercised their rights to convert their Series A preferred units into 21 million common units and 2 million common units, respectively. Approximately 6 million Series A preferred units were outstanding as of December 31, 2024. On February 11, 2025, MPLX exercised its right to convert the remaining outstanding Series A preferred units into common units.

For a summary of changes in the redeemable preferred balance, see the accompanying consolidated statements of equity and redeemable noncontrollable interest.

Redemption of the Series B Preferred Units

On February 15, 2023, MPLX exercised its right to redeem all of its 600,000 outstanding preferred units (the “Series B preferred units”). MPLX paid unitholders the Series B preferred unit redemption price of $1,000 per unit. The final semi-annual distribution on the Series B preferred units was paid on February 15, 2023 in the usual manner.

The excess of the total redemption price of $600 million paid to Series B preferred unitholders over the carrying value of the Series B preferred units on the redemption date resulted in a $2 million net reduction to retained earnings.

Agreements

We have various long-term, fee-based commercial agreements with MPLX. Under these agreements, MPLX provides transportation, storage, distribution and marketing services to us. With certain exceptions, these agreements generally contain minimum volume commitments. These transactions are eliminated in consolidation but are reflected as intersegment transactions among our Refining & Marketing, Renewable Diesel and Midstream segments. We also have agreements with MPLX that establish fees for operational and management services provided between us and MPLX and for executive management services and certain general and administrative services provided by us to MPLX. These transactions are eliminated in consolidation but are reflected as intersegment transactions between corporate and our Midstream segment.

Noncontrolling Interest

As a result of equity transactions of MPLX, we are required to adjust non-controlling interest and additional paid-in capital. Changes in MPC’s additional paid-in capital resulting from changes in its ownership interest in MPLX were as follows: