Marathon Petroleum Corporation
US ˙ NYSE ˙ US56585A1025

SecurityMPC / Marathon Petroleum Corporation
InstitutionColdstream Capital Management Inc
Latest Disclosed Ownership18,478 shares
Latest Disclosed Value $ 4,511,947
Coldstream Capital Management Inc reports 132.63% increase in ownership of MPC / Marathon Petroleum Corporation

On May 8, 2026 - Coldstream Capital Management Inc filed a 13F-HR form disclosing ownership of 18,478 shares of Marathon Petroleum Corporation (US:MPC) valued at $4,511,958 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 9, 2026 disclosing 7,943 shares of Marathon Petroleum Corporation. This represents a change in shares of 132.63% during the quarter. The current value of the position is $4,937,506 USD.

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)
2026-05-08 2026-03-31 13F MARATHON PETE COM 56585A102 18,478 10,535 132.63 4,512 249.42 0.0484
2026-02-09 2025-12-31 13F MARATHON PETE COM 56585A102 7,943 1,024 14.80 1,292 -3.15 0.0167
2025-11-19 2025-09-30 13F MARATHON PETE COM 56585A102 6,919 -10,945 -61.27 1,334 -55.07 0.0180
2025-08-12 2025-06-30 13F MARATHON PETE COM 56585A102 17,864 -2,198 -10.96 2,967 1.54 0.0485
2025-05-13 2025-03-31 13F MARATHON PETE COM 56585A102 20,062 -75 -0.37 2,923 4.02 0.0622
2025-02-14 2024-12-31 13F MARATHON PETE COM 56585A102 20,137 183 0.92 2,809 -13.52 0.0599
2024-11-18 2024-09-30 13F/A-1 MARATHON PETE COM 56585A102 19,954 280 1.42 3,249 -4.83 0.0702
2024-11-18 2024-09-30 13F MARATHON PETE COM 56585A102 19,954 3,249
2024-08-07 2024-06-30 13F MARATHON PETE COM 56585A102 19,674 3,116 18.82 3,413 2.31 0.0832
2024-05-14 2024-03-31 13F MARATHON PETE COM 56585A102 16,558 -37 -0.22 3,336 35.50 0.0847
2024-02-09 2023-12-31 13F MARATHON PETE COM 56585A102 16,595 -217 -1.29 2,462 -3.22 0.0689
2023-11-02 2023-09-30 13F MARATHON PETE COM 56585A102 16,812 -192 -1.13 2,544 28.36 0.0831
2023-08-03 2023-06-30 13F MARATHON PETE COM 56585A102 17,004 -708 -4.00 1,983 -17.00 0.0628
2023-05-15 2023-03-31 13F MARATHON PETE COM 56585A102 17,712 -64 -0.36 2,388 15.47 0.0802
2023-01-10 2022-12-31 13F MARATHON PETE COM 56585A102 17,776 791 4.66 2,069 48.03 0.0757
2022-08-08 2022-06-30 13F/A-1 MARATHON PETE COM 56585A102 16,985 -1,439 -7.81 1,397 -11.30 0.0544
2022-08-08 2022-06-30 13F MARATHON PETE COM 56585A102 13,886 -4,538 1,142 0.0486
2022-05-11 2022-03-31 13F MARATHON PETE COM 56585A102 18,424 -2,661 -12.62 1,575 16.75 0.0543
2022-02-11 2021-12-31 13F MARATHON PETE COM 56585A102 21,085 -68,809 -76.54 1,349 -48.84 0.0424
2021-11-12 2021-09-30 13F MARATHON PETE COM 56585A102 89,894 72,142 406.39 2,637 145.76 0.1278
2021-08-16 2021-06-30 13F MARATHON PETE COM 56585A102 17,752 -15,266 -46.24 1,073 -39.24 0.0432
2021-06-16 2021-03-31 13F MARATHON PETE COM 56585A102 33,018 -3,826 -10.38 1,766 15.88 0.1034
2021-02-16 2020-12-31 13F MARATHON PETE COM 56585A102 36,844 -51,382 -58.24 1,524 -41.11 0.0919
2020-11-16 2020-09-30 13F MARATHON PETE COM 56585A102 88,226 51,202 138.29 2,588 86.99 0.2154
2020-08-12 2020-06-30 13F MARATHON PETE COM 56585A102 37,024 692 1.90 1,384 61.31 0.1243
2020-05-27 2020-03-31 13F MARATHON PETE COM 56585A102 36,332 -1,291 -3.43 858 -62.14 0.0938
2020-02-13 2019-12-31 13F MARATHON PETE COM 56585A102 37,623 207 0.55 2,266 -0.31 0.1858
2019-11-15 2019-09-30 13F MARATHON PETE COM 56585A102 37,416 -216 -0.57 2,273 8.08 0.1914
2019-08-15 2019-06-30 13F MARATHON PETE COM 56585A102 37,632 725 1.96 2,103 -4.80 0.1750
2019-05-10 2019-03-31 13F MARATHON PETE COM 56585A102 36,907 -122 -0.33 2,209 1.10 0.1932
2019-02-26 2018-12-31 13F MARATHON PETE COM 56585A102 37,029 37,029 2,185 0.2121
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.