Marathon Petroleum Corporation
MX ˙ BMV ˙ US56585A1025
SecurityMX:MPC / Marathon Petroleum Corporation
InstitutionCSM Advisors, LLC
Latest Disclosed Ownership18,620 shares
Latest Disclosed Value $ 4,547
CSM Advisors, LLC reports 3.83% decrease in ownership of MPC / Marathon Petroleum Corporation

On May 15, 2026 - CSM Advisors, LLC filed a 13F-HR form disclosing ownership of 18,620 shares of Marathon Petroleum Corporation (MX:MPC) valued at $4,547 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 19,362 shares of Marathon Petroleum Corporation. This represents a change in shares of -3.83% 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 PETROLEUM COMMON 56585A102 18,620 -742 -3.83 5 33.33 0.1117
2026-02-11 2025-12-31 13F MARATHON PETROLEUM COMMON 56585A102 19,362 -22,005 -53.19 3 -57.14 0.0855
2025-11-14 2025-09-30 13F MARATHON PETROLEUM COMMON 56585A102 41,367 -85,128 -67.30 8 -66.67 0.2229
2025-08-07 2025-06-30 13F MARATHON PETROLEUM COMMON 56585A102 126,495 1,288 1.03 21 16.67 0.6129
2025-05-14 2025-03-31 13F MARATHON PETROLEUM COMMON 56585A102 125,207 -2,415 -1.89 18 5.88 0.9951
2025-02-14 2024-12-31 13F/A-1 MARATHON PETROLEUM COMMON 56585A102 127,622 -4,185 -3.18 18 -19.05 0.8326
2025-02-14 2024-12-31 13F MARATHON PETROLEUM COMMON 56585A102 127,622 -4,185 18 1.1796
2024-11-14 2024-09-30 13F MARATHON PETROLEUM COMMON 56585A102 131,807 -4,785 -3.50 21 -8.70 1.3994
2024-08-14 2024-06-30 13F MARATHON PETROLEUM COMMON 56585A102 136,592 -10,204 -6.95 24 -20.69 1.6706
2024-05-15 2024-03-31 13F MARATHON PETROLEUM COMMON 56585A102 146,796 1,875 1.29 30 38.10 1.9418
2024-02-14 2023-12-31 13F MARATHON PETROLEUM COMMON 56585A102 144,921 -1,803 -1.23 22 -4.55 1.5481
2023-11-13 2023-09-30 13F MARATHON PETROLEUM COMMON 56585A102 146,724 -2,090 -1.40 22 29.41 1.9331
2023-08-14 2023-06-30 13F MARATHON PETROLEUM COMMON 56585A102 148,814 -6,020 -3.89 17 -15.00 1.3104
2023-05-15 2023-03-31 13F MARATHON PETROLEUM COMMON 56585A102 154,834 13,240 9.35 21 25.00 1.8025
2023-02-14 2022-12-31 13F MARATHON PETROLEUM COMMON 56585A102 141,594 930 0.66 16 -99.89 1.5687
2022-11-14 2022-09-30 13F MARATHON PETROLEUM COMMON 56585A102 140,664 -25,475 -15.33 13,976 2.34 1.5275
2022-08-11 2022-06-30 13F MARATHON PETROLEUM COMMON 56585A102 166,139 1,200 0.73 13,657 -3.17 1.2479
2022-05-16 2022-03-31 13F MARATHON PETROLEUM COMMON 56585A102 164,939 -19,435 -10.54 14,104 19.55 0.9653
2022-02-09 2021-12-31 13F MARATHON PETROLEUM COMMON 56585A102 184,374 -4,340 -2.30 11,798 1.11 0.7807
2021-11-15 2021-09-30 13F MARATHON PETROLEUM COMMON 56585A102 188,714 1,500 0.80 11,668 3.15 0.8614
2021-08-16 2021-06-30 13F MARATHON PETROLEUM COMMON 56585A102 187,214 -8,130 -4.16 11,312 8.26 0.7472
2021-05-21 2021-03-31 13F MARATHON PETRO COMMON 56585A102 195,344 195,344 10,449 1.4697
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.