Marathon Petroleum Corp. Elects Maryann T. Mannen as Chairman of the Board

Rhea-AI Summary

Marathon Petroleum (NYSE:MPC) announced that its board elected Maryann T. Mannen as chairman of the board, effective Jan. 1, 2026. Mannen will retain her current responsibilities as president and chief executive officer while serving as chairman.

She succeeds Michael J. Hennigan, who will retire as executive chairman and as a board member effective Jan. 1, 2026. John Surma will continue as independent lead director. The release summarizes Mannen’s internal progression: CEO since Aug. 2024, president since Jan. 2024, and EVP & CFO from Jan. 2021 to Jan. 2024.

Positive

• Internal succession: Mannen promoted to chairman effective Jan. 1, 2026
• Leadership continuity: Mannen has been CEO since Aug. 2024
• Independent oversight maintained: John Surma to remain independent lead director

Negative

• Role consolidation: Mannen will hold both CEO and chairman roles starting Jan. 1, 2026
• Loss of outgoing chairman: Hennigan will retire as executive chairman and board member on Jan. 1, 2026

News Market Reaction – MPC

-6.13%

24 alerts

-6.13% News Effect

-4.4% Trough in 3 hr 46 min

-$3.89B Valuation Impact

$59.52B Market Cap

0.8x Rel. Volume

On the day this news was published, MPC declined 6.13%, reflecting a notable negative market reaction. Argus tracked a trough of -4.4% from its starting point during tracking. Our momentum scanner triggered 24 alerts that day, indicating elevated trading interest and price volatility. This price movement removed approximately $3.89B from the company's valuation, bringing the market cap to $59.52B at that time.

Data tracked by StockTitan Argus on the day of publication.

FINDLAY, Ohio, Nov. 4, 2025 /PRNewswire/ -- Marathon Petroleum Corp. (NYSE: MPC) today announced that the board of directors of MPC has elected Maryann T. Mannen, president and chief executive officer and member of the board of directors, as chairman of the board, effective Jan. 1, 2026. Mannen will assume the role of chairman of the board in addition to her current responsibilities. Mannen will succeed Michael J. Hennigan, who has elected to retire as executive chairman and as a member of the board of directors, also effective Jan. 1, 2026. John Surma will continue to serve as independent lead director of the board.

"We congratulate Maryann as our new chairman of the board," said Mr. Surma. "We are confident in Maryann's leadership and enthusiastic about our company's direction. We thank Mike for his exemplary service during a period of significant value creation."

"Mike's continued leadership and remarkable achievements have been pivotal for MPC's positive trajectory," said Ms. Mannen. "It's an honor to succeed Mike as chairman of the board and to have the opportunity to build on that legacy of leadership and success, taking our performance to the next level. I appreciate the trust our board has placed in me as we look ahead to MPC's future."

Mr. Hennigan led MPC as CEO beginning in March 2020 and transitioned from CEO to executive chairman in August 2024. Ms. Mannen has served as CEO since August 2024, after previously serving as president from January 2024, and as executive vice president and chief financial officer between January 2021 and January 2024.

About Marathon Petroleum Corporation

MPC is a leading, integrated, downstream and midstream energy company headquartered in Findlay, Ohio. The company operates the nation's largest refining system. MPC's marketing system includes branded locations across the United States, including Marathon brand retail outlets. MPC also owns the general partner and majority limited partner interest in MPLX LP, a midstream company that owns and operates gathering, processing, and fractionation assets, as well as crude oil and light product transportation and logistics infrastructure. More information is available at www.marathonpetroleum.com.

Investor Relations Contacts: (419) 421-2071
Kristina Kazarian, Vice President Finance and Investor Relations
Brian Worthington, Senior Director, Investor Relations
Alyx Teschel, Director, Investor Relations

Media Contact: (419) 421-3577
Jamal Kheiry, Communications Manager

 

View original content:https://www.prnewswire.com/news-releases/marathon-petroleum-corp-elects-maryann-t-mannen-as-chairman-of-the-board-302603750.html

SOURCE Marathon Petroleum Corporation

FAQ

Who was elected chairman of Marathon Petroleum (MPC) and when does the change take effect?

Maryann T. Mannen was elected chairman and the change is effective Jan. 1, 2026.

Will Maryann Mannen keep her CEO role after becoming chairman of MPC (NYSE:MPC)?

Yes. Mannen will assume the chairman role in addition to her current CEO responsibilities.

What happens to Michael J. Hennigan at Marathon Petroleum (MPC)?

Michael J. Hennigan will retire as executive chairman and as a board member effective Jan. 1, 2026.

Who will serve as independent lead director on Marathon Petroleum’s board after the change?

John Surma will continue to serve as independent lead director.

What is Maryann Mannen’s track record at Marathon Petroleum prior to becoming chairman?

Mannen has served as CEO since Aug. 2024, president since Jan. 2024, and EVP & CFO from Jan. 2021 to Jan. 2024.