Summary
MPLX LP (MPLX) has announced a significant leadership transition effective January 1, 2026. Maryann T. Mannen, currently President and Chief Executive Officer, will assume the additional role of Chairman of the Board. This transition follows the decision of Michael J. Hennigan to retire as Executive Chairman and depart the board of directors as of the same date. Ms. Mannen's dual role as CEO and Chairman signals a continuation of leadership strategy. The board of directors for MPLX GP LLC will be reduced to 10 members following Mr. Hennigan's retirement. The company issued a press release on November 4, 2025, to formally announce these changes.
Key Highlights
- 1Maryann T. Mannen appointed as Chairman of the Board, effective January 1, 2026.
- 2Ms. Mannen will retain her current roles as President and Chief Executive Officer.
- 3Michael J. Hennigan to retire as Executive Chairman and step down from the board on January 1, 2026.
- 4The retirement of Mr. Hennigan will result in a reduction of the MPLX GP board size to 10 directors.
- 5Leadership transition is effective at the start of the new year (January 1, 2026).
- 6The company formally announced these changes via a press release on November 4, 2025.