---
schema_version: "secwatch.filing_event.v1"
accession: "0001510295-25-000065"
form_type: "8-K"
ticker: "MPC"
cik: "0001510295"
company_name: "Marathon Petroleum Corp"
filed_at: "2025-11-04T23:59:59+00:00"
generated_at: "2026-05-17T00:36:31.200526+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.55
calibrated_materiality_score: 0.55
confidence: "high"
source: SEC EDGAR
---

# MPC CEO Maryann Mannen elected Chairman; Michael Hennigan retires as Executive Chairman

## Summary
- Maryann T. Mannen (president and CEO) elected Chairman of the Board effective Jan 1, 2026, retaining CEO role.
- Michael J. Hennigan retires as Executive Chairman and from the Board, effective Jan 1, 2026.
- John Surma continues as independent lead director; Board size reduces to 11 directors.
- Hennigan served as CEO from March 2020 to August 2024, then Executive Chairman.

## SEC filing metadata
- accession: 0001510295-25-000065
- form_type: 8-K
- ticker: MPC
- cik: 0001510295
- company_name: Marathon Petroleum Corp
- filed_at: 2025-11-04T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.55
- calibrated_materiality_score: 0.55
- confidence: high
- sec_items: 5.02, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1510295/000151029525000065/0001510295-25-000065-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1510295/000151029525000065/mpc-20251029.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001510295-25-000065
- JSON: https://secwatch.observer/filing/0001510295-25-000065.json
- Plain text: https://secwatch.observer/filing/0001510295-25-000065.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.