Marathon Petroleum Corporation
MX ˙ BMV ˙ US56585A1025
SecurityMX:MPC / Marathon Petroleum Corporation
InstitutionGWM Advisors LLC
Latest Disclosed Ownership60,998 shares
Latest Disclosed Value $ 4,966,924
GWM Advisors LLC reports 31.64% decrease in ownership of MPC / Marathon Petroleum Corporation

On May 15, 2026 - GWM Advisors LLC filed a 13F-HR form disclosing ownership of 60,998 shares of Marathon Petroleum Corporation (MX:MPC) valued at $4,966,924 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 18, 2026 disclosing 89,228 shares of Marathon Petroleum Corporation. This represents a change in shares of -31.64% 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)
2026-05-15 2026-03-31 13F MARATHON PETE COM 56585A102 60,998 -28,230 -31.64 4,967 -65.78 0.2300
2026-02-18 2025-12-31 13F MARATHON PETE COM 56585A102 89,228 5,872 7.04 14,511 -9.67 0.0527
2025-11-17 2025-09-30 13F MARATHON PETROLEUM Common Stock 56585A102 83,356 -4,726 -5.37 16,066 9.80 0.0730
2025-08-14 2025-06-30 13F MARATHON PETE COM 56585A102 88,082 2,282 2.66 14,631 17.05 0.0754
2025-05-15 2025-03-31 13F MARATHON PETROLEUM Common Stock 56585A102 85,800 -1,311 -1.50 12,500 2.86 0.0743
2025-02-13 2024-12-31 13F MARATHON PETE COM 56585A102 87,111 -10,389 -10.66 12,152 -23.49 0.0730
2024-11-14 2024-09-30 13F MARATHON PETE COM 56585A102 97,500 -4,373 -4.29 15,884 -10.12 0.1030
2024-08-16 2024-06-30 13F MARATHON PETE COM 56585A102 101,873 7,704 8.18 17,673 -6.87 0.1287
2024-05-14 2024-03-31 13F MARATHON PETE COM 56585A102 94,169 13,061 16.10 18,975 54.23 0.1655
2024-02-13 2023-12-31 13F MARATHON PETE COM 56585A102 81,108 -2,039 -2.45 12,304 -2.23 0.1168
2023-11-14 2023-09-30 13F MARATHON PETE COM 56585A102 83,147 1,095 1.33 12,583 31.53 0.1383
2023-08-14 2023-06-30 13F MARATHON PETE COM 56585A102 82,052 -5,024 -5.77 9,567 -17.56 0.1081
2023-05-12 2023-03-31 13F MARATHON PETE COM 56585A102 87,076 11,208 14.77 11,605 127.73 0.1451
2023-02-14 2022-12-31 13F MARATHON PETE COM 56585A102 75,868 4,753 6.68 5,097 -27.86 0.1375
2022-11-14 2022-09-30 13F MARATHON PETROLEUM COM 56585A102 71,115 -10,726 -13.11 7,064 4.99 0.1161
2022-08-09 2022-06-30 13F MARATHON PETE COM 56585A102 81,841 19,799 31.91 6,728 26.85 0.1115
2022-05-13 2022-03-31 13F MARATHON PETE COM 56585A102 62,042 -4,600 -6.90 5,304 24.39 0.0853
2022-02-17 2021-12-31 13F MARATHON PETE COM 56585A102 66,642 31,111 87.56 4,264 94.17 0.0643
2021-10-29 2021-09-30 13F MARATHON PETROLEUM Common Stock 56585A102 35,531 -11,345 -24.20 2,196 -22.48 0.0543
2021-07-22 2021-06-30 13F MARATHON PETROLEUM Common Stock 56585A102 46,876 10,801 29.94 2,833 46.79 0.0754
2021-04-26 2021-03-31 13F MARATHON PETROLEUM Common Stock 56585A102 36,075 2,438 7.25 1,930 38.75 0.0575
2021-01-27 2020-12-31 13F MARATHON PETROLEUM Common Stock 56585A102 33,637 -5,170 -13.32 1,391 22.12 0.0456
2020-11-03 2020-09-30 13F MARATHON PETROLEUM Common Stock 56585A102 38,807 21,198 120.38 1,139 73.10 0.0396
2020-07-29 2020-06-30 13F MARATHON PETROLEUM Common Stock 56585A102 17,609 -2,954 -14.37 658 35.39 0.0257
2020-05-04 2020-03-31 13F MARATHON PETROLEUM COM 56585A102 20,563 6,485 46.06 486 -42.69 0.0234
2020-01-31 2019-12-31 13F MARATHON PETROLEUM Common Stock 56585A102 14,078 3,744 36.23 848 33.97 0.0337
2019-11-06 2019-09-30 13F MARATHON PETE COM 56585A102 10,334 973 10.39 633 21.03 0.0281
2019-08-05 2019-06-30 13F MARATHON PETE COM 56585A102 9,361 3,092 49.32 523 39.47 0.0320
2019-05-14 2019-03-31 13F/A-1 MARATHON PETE COM 56585A102 6,269 -5,348 -46.04 375 -45.34 0.0242
2019-05-09 2019-03-31 13F MARATHON PETE COM 56585A102 13,312 1,695 11
2019-01-28 2018-12-31 13F MARATHON PETE COM 56585A102 11,617 6,343 120.27 686 62.56 0.0442
2018-10-29 2018-09-30 13F MARATHON PETE COM 56585A102 5,274 757 16.76 422 33.12 0.0324
2018-07-19 2018-06-30 13F MARATHON PETE COM 56585A102 4,517 1,115 32.77 317 29.92 0.0290
2018-05-11 2018-03-31 13F MARATHON PETE COM 56585A102 3,402 27 0.80 244 4.27 0.0279
2018-02-08 2017-12-31 13F MARATHON PETE COM 56585A102 3,375 3,375 234 0.0316
2017-11-13 2017-09-30 13F ABBVIE Common Stock 56585A102 0 -3,375 -100.00 0 -100.00
2017-08-17 2017-06-30 13F/A-1 MARATHON PETROLEUM Common Stock 56585A102 3,375 3,375 183 0.0314
2017-08-16 2017-06-30 13F ABBVIE Common Stock 56585A102 3,375 183
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.