Marathon Petroleum Corp
Ownership
Ownership Structure
Who owns Marathon Petroleum Corp (MPC)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 99.7% of the shares are freely tradable; institutional investors hold 78.5%.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| BlackRock Inc | 8.69 | 24,394,842 | +8.8 | 03/31/2026 |
| Vanguard Capital Management, LLC | 6.83 | 19,170,094 | +0.0 | 03/31/2026 |
| State Street Corp | 6.77 | 19,025,020 | +6.1 | 03/31/2026 |
| Vanguard Portfolio Management, LLC | 5.58 | 15,672,113 | +0.0 | 03/31/2026 |
| Geode Capital Management, LLC | 2.79 | 7,821,524 | +0.7 | 03/31/2026 |
| Morgan Stanley - Brokerage Accounts | 2.16 | 6,073,543 | -0.2 | 03/31/2026 |
Funds
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| Cushing Midstream Strategy | 5.09 | 14,296,191 | +2.3 | 06/30/2026 |
| Vanguard MStar Total Stk Mkt Idx Invest | 3.31 | 9,295,714 | +0.3 | 07/31/2026 |
| Vanguard 500 Index Investor | 2.73 | 7,662,942 | +1.1 | 07/31/2026 |
| Vanguard MStar Mid Cap Index Instl | 2.25 | 6,318,108 | -0.1 | 07/31/2026 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Insider holdings
| Person | Role | Shares | Value | As of | Type |
|---|---|---|---|---|---|
| Mannen Maryann T. | Chairman, President & CEO | 110,939 | 47,137,981 $ | Aug 3, 2026 | direct |
| Benson Molly R | Chief Legal Ofc & Corp Sec | 30,334 | 12,889,058 $ | Aug 17, 2026 | direct |
| Lyon Shawn M | SVP Log & Storage, MPLX GP LLC | 11,194 | 4,756,331 $ | Aug 31, 2026 | direct |
| Henschen Michael A II | Ex VP, Refining | 10,889 | 4,626,736 $ | Aug 12, 2026 | direct |
| Brzezinski Erin M | VP and Controller | 1,576 | 669,642 $ | Aug 27, 2026 | direct |
Holdings as of each person's most recent SEC Form 4 filing — excluding options and RSUs, which are not shares yet. Holdings may have changed between two filings.
Insiders
Insider Transactions
| Date | Person | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Aug 31, 2026 | Lyon Shawn M | SVP Log & Storage, MPLX GP LLC | Sell | 1,000 | 375.75 | 375,750 |
| Aug 28, 2026 | Lyon Shawn M | SVP Log & Storage, MPLX GP LLC | Sell | 425 | 368.51 | 156,617 |
| Aug 27, 2026 | Brzezinski Erin M | VP and Controller | Sell | 570 | 362.79 | 206,790 |
| Aug 17, 2026 | Benson Molly R | Chief Legal Ofc & Corp Sec | Sell | 5,000 | 358.57 | 1,792,850 |
| Aug 17, 2026 | Benson Molly R | Chief Legal Ofc & Corp Sec | Other | 5,000 | 47.73 | 238,650 |
| Aug 17, 2026 | Benson Molly R | Chief Legal Ofc & Corp Sec | Sell | 7,196 | 358.57 | 2,580,270 |
| Aug 17, 2026 | Benson Molly R | Chief Legal Ofc & Corp Sec | Other | 7,196 | 47.73 | 343,465 |
| Aug 13, 2026 | Lyon Shawn M | SVP Log & Storage, MPLX GP LLC | Sell | 2,500 | 350.00 | 875,000 |
| Aug 12, 2026 | Henschen Michael A II | Ex VP, Refining | Sell | 6,011 | 341.56 | 2,053,099 |
| Aug 3, 2026 | Mannen Maryann T. | Chairman, President & CEO | Other | 908 | 311.78 | 283,096 |
Reportable transactions by officers and major shareholders from SEC Form 4 filings. "Other" includes things like stock grants and option exercises without a buy/sell character. View all insider transactions →
Data as of: September 18, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.