Marathon Petroleum Corporation
MX ˙ BMV ˙ US56585A1025
SecurityMX:MPC / Marathon Petroleum Corporation
InstitutionAffinity Investment Advisors, Llc
Latest Disclosed Ownership2,406 shares
Latest Disclosed Value $ 587,497
Affinity Investment Advisors, Llc reports 15.62% increase in ownership of MPC / Marathon Petroleum Corporation

On May 14, 2026 - Affinity Investment Advisors, Llc filed a 13F-HR form disclosing ownership of 2,406 shares of Marathon Petroleum Corporation (MX:MPC) valued at $587,497 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 2,081 shares of Marathon Petroleum Corporation. This represents a change in shares of 15.62% 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 PETE COM 56585A102 2,406 325 15.62 587 73.67 0.3675
2026-02-12 2025-12-31 13F MARATHON PETE COM 56585A102 2,081 2,081 338 0.2248
2025-02-11 2024-12-31 13F MARATHON PETE COM 56585A102 0 -1,367 -100.00 0 -100.00
2024-10-28 2024-09-30 13F MARATHON PETE COM 56585A102 1,367 -5,413 -79.84 223 -81.12 0.1528
2024-08-13 2024-06-30 13F MARATHON PETE COM 56585A102 6,780 -1,050 -13.41 1,176 -25.43 0.8835
2024-05-03 2024-03-31 13F MARATHON PETE COM 56585A102 7,830 -130 -1.63 1,578 33.64 1.1516
2024-02-09 2023-12-31 13F MARATHON PETE COM 56585A102 7,960 -415 -4.96 1,181 -6.87 0.8033
2023-10-26 2023-09-30 13F MARATHON PETE COM 56585A102 8,375 -728 -8.00 1,267 19.42 0.8180
2023-08-10 2023-06-30 13F MARATHON PETE COM 56585A102 9,103 870 10.57 1,061 -4.41 0.6145
2023-05-05 2023-03-31 13F MARATHON PETE COM 56585A102 8,233 5,593 211.86 1,110 261.56 0.5934
2023-02-08 2022-12-31 13F MARATHON PETE COM 56585A102 2,640 -2,240 -45.90 307 -36.70 0.1413
2022-11-08 2022-09-30 13F MARATHON PETE COM 56585A102 4,880 0 0.00 485 20.95 0.2517
2022-07-27 2022-06-30 13F MARATHON PETE COM 56585A102 4,880 1,500 44.38 401 38.75 0.1957
2022-05-05 2022-03-31 13F MARATHON PETE COM 56585A102 3,380 3,380 289 0.1184
2020-11-13 2020-09-30 13F MARATHON PETROLEUM COM 56585A102 0 -50,765 -100.00 0 -100.00
2020-08-13 2020-06-30 13F MARATHON PETROLEUM COM 56585A102 50,765 -16,901 -24.98 1,898 18.77 0.9017
2020-05-15 2020-03-31 13F MARATHON PETROLEUM COM 56585A102 67,666 6,013 9.75 1,598 -56.99 0.8142
2020-02-13 2019-12-31 13F MARATHON PETROLEUM COM 56585A102 61,653 -19,055 -23.61 3,715 -24.23 1.3474
2019-11-12 2019-09-30 13F MARATHON PETROLEUM COM 56585A102 80,708 -10,380 -11.40 4,903 -3.67 1.5386
2019-08-08 2019-06-30 13F MARATHON PETE COM 56585A102 91,088 -7,633 -7.73 5,090 -13.85 1.4597
2019-05-07 2019-03-31 13F MARATHON PETROLEUM COM 56585A102 98,721 -39,805 -28.73 5,908 -27.72 1.2110
2019-02-05 2018-12-31 13F MARATHON PETROLEUM COM 56585A102 138,526 -4,173 -2.92 8,174 -28.37 1.4290
2018-11-09 2018-09-30 13F MARATHON PETROLEUM COM 56585A102 142,699 -13,827 -8.83 11,412 3.92 1.5039
2018-08-06 2018-06-30 13F MARATHON PETROLEUM COM 56585A102 156,526 -34,443 -18.04 10,982 -21.34 1.5517
2018-05-08 2018-03-31 13F MARATHON PETROLEUM COM 56585A102 190,969 10,638 5.90 13,962 17.35 1.6310
2018-02-07 2017-12-31 13F MARATHON PETROLEUM COM 56585A102 180,331 -19,021 -9.54 11,898 6.42 1.3502
2017-10-31 2017-09-30 13F MARATHON PETROLEUM COM 56585A102 199,352 -2,041 -1.01 11,180 6.08 1.2960
2017-07-25 2017-06-30 13F MARATHON PETROLEUM COM 56585A102 201,393 -54,225 -21.21 10,539 -18.42 1.2575
2017-05-04 2017-03-31 13F MARATHON PETROLEUM COM 56585A102 255,618 255,618 12,919 1.1692
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.