Marathon Petroleum Corporation
MX ˙ BMV ˙ US56585A1025
SecurityMX:MPC / Marathon Petroleum Corporation
InstitutionBrown Brothers Harriman & Co
Latest Disclosed Ownership7,650 shares
Latest Disclosed Value $ 1,867,977
Brown Brothers Harriman & Co reports 46.22% increase in ownership of MPC / Marathon Petroleum Corporation

On May 14, 2026 - Brown Brothers Harriman & Co filed a 13F-HR form disclosing ownership of 7,650 shares of Marathon Petroleum Corporation (MX:MPC) valued at $1,867,977 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 5,232 shares of Marathon Petroleum Corporation. This represents a change in shares of 46.22% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-14 2026-03-31 13F MARATHON PETROLEUM Common Stock 56585A102 7,650 2,418 46.22 1,868 119.65 0.0100
2026-02-12 2025-12-31 13F MARATHON PETROLEUM Common Stock 56585A102 5,232 121 2.37 851 -13.71 0.0046
2025-11-13 2025-09-30 13F MARATHON PETROLEUM Common Stock 56585A102 5,111 514 11.18 985 29.10 0.0060
2025-08-11 2025-06-30 13F MARATHON PETROLEUM Common Stock 56585A102 4,597 146 3.28 764 17.75 0.0049
2025-05-14 2025-03-31 13F MARATHON PETROLEUM Common Stock 56585A102 4,451 58 1.32 648 5.88 0.0045
2025-02-12 2024-12-31 13F MARATHON PETROLEUM Common Stock 56585A102 4,393 -942 -17.66 613 -29.57 0.0043
2024-11-13 2024-09-30 13F MARATHON PETROLEUM Common Stock 56585A102 5,335 1,997 59.83 869 50.09 0.0059
2024-08-09 2024-06-30 13F MARATHON PETROLEUM Common Stock 56585A102 3,338 2,641 378.91 579 313.57 0.0044
2024-05-10 2024-03-31 13F MARATHON PETROLEUM Common Stock 56585A102 697 0 0.00 140 35.92 0.0011
2024-02-12 2023-12-31 13F MARATHON PETROLEUM Common Stock 56585A102 697 -1 -0.14 103 -1.90 0.0009
2023-11-13 2023-09-30 13F MARATHON PETROLEUM Common Stock 56585A102 698 -186 -21.04 106 1.94 0.0009
2023-08-07 2023-06-30 13F MARATHON PETROLEUM Common Stock 56585A102 884 -72 -7.53 103 -19.53 0.0008
2023-05-11 2023-03-31 13F MARATHON PETROLEUM Common Stock 56585A102 956 -982 -50.67 129 -43.11 0.0011
2023-02-09 2022-12-31 13F MARATHON PETROLEUM Common Stock 56585A102 1,938 -186 -8.76 226 6.64 0.0020
2022-11-14 2022-09-30 13F MARATHON PETROLEUM Common Stock 56585A102 2,124 283 15.37 211 39.74 0.0020
2022-08-11 2022-06-30 13F MARATHON PETROLEUM Common Stock 56585A102 1,841 238 14.85 151 10.22 0.0013
2022-05-13 2022-03-31 13F MARATHON PETROLEUM Common Stock 56585A102 1,603 1,371 590.95 137 813.33 0.0010
2022-02-14 2021-12-31 13F MARATHON PETROLEUM Common Stock 56585A102 232 0 0.00 15 7.14 0.0001
2021-11-15 2021-09-30 13F MARATHON PETROLEUM Common Stock 56585A102 232 0 0.00 14 0.00 0.0001
2021-08-13 2021-06-30 13F MARATHON PETROLEUM Common Stock 56585A102 232 20 9.43 14 27.27 0.0001
2021-05-13 2021-03-31 13F MARATHON PETROLEUM Common Stock 56585A102 212 -936 -81.53 11 -76.60 0.0001
2021-02-16 2020-12-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,148 84 7.89 47 51.61 0.0003
2020-11-16 2020-09-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,064 -253 -19.21 31 -36.73 0.0002
2020-08-13 2020-06-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,317 1,273 2,893.18 49 4,800.00 0.0004
2020-05-15 2020-03-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 44 -2,937 -98.52 1 -99.44 0.0000
2020-02-14 2019-12-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 2,981 1,329 80.45 180 80.00 0.0012
2019-11-14 2019-09-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,652 -160 -8.83 100 -0.99 0.0007
2019-08-14 2019-06-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,812 94 5.47 101 -1.94 0.0007
2019-05-15 2019-03-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,718 -232 -11.90 103 -10.43 0.0007
2019-02-14 2018-12-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,950 255 15.04 115 -15.44 0.0009
2018-11-14 2018-09-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,695 123 7.82 136 23.64 0.0009
2018-08-14 2018-06-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,572 0 0.00 110 -4.35 0.0007
2018-05-14 2018-03-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,572 -268 -14.57 115 -4.96 0.0007
2018-02-14 2017-12-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,840 135 7.92 121 26.04 0.0007
2017-11-14 2017-09-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,705 0 0.00 96 7.87 0.0005
2017-08-14 2017-06-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,705 -2,141 -55.67 89 -54.12 0.0005
2017-05-12 2017-03-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 3,846 274 7.67 194 7.78 0.0011
2017-02-14 2016-12-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 3,572 0 0.00 180 24.14 0.0010
2016-11-14 2016-09-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 3,572 0 0.00 145 6.62 0.0008
2016-08-15 2016-06-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 3,572 0 0.00 136 2.26 0.0007
2016-05-13 2016-03-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 3,572 -94 -2.56 133 -30.00 0.0007
2016-02-12 2015-12-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 3,666 -100 -2.66 190 9.20 0.0010
2015-11-13 2015-09-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 3,766 266 7.60 174 -4.92 0.0009
2015-08-14 2015-06-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 3,500 3,452 7,191.67 183 3,560.00 0.0009
2015-05-15 2015-03-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 48 -20 -29.41 5 -16.67 0.0000
2015-02-13 2014-12-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 68 -365 -84.30 6 -83.78 0.0000
2014-11-14 2014-09-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 433 152 54.09 37 68.18 0.0001
2014-08-15 2014-06-30 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 281 -1,044 -78.79 22 -80.87 0.0001
2014-05-15 2014-03-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 1,325 818 161.34 115 144.68 0.0005
2014-05-13 2013-12-31 13F/A-2 MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 507 507 -27.57 47 -6.00 0.0002
2014-02-12 2013-12-31 13F MARATHON PETROLEUM CORP COM STK Common Stock 56585A102 507 47
2013-11-14 2013-09-30 13F MARATHON PETROLEUM Common 56585A102 0 -700 -100.00 0 -100.00
2013-08-12 2013-06-30 13F MARATHON PETROLEUM Common 56585A102 700 -1,290 -64.82 50 -71.91 0.0002
2013-05-23 2013-03-31 13F/A-1 MARATHON PETROLEUM Common 56585A102 1,990 1,990 178 0.0009
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.