Marathon Petroleum Corporation
MX ˙ BMV ˙ US56585A1025
SecurityMX:MPC / Marathon Petroleum Corporation
InstitutionOMERS ADMINISTRATION Corp
Latest Disclosed Ownership29,191 shares
Latest Disclosed Value $ 7,127,858
OMERS ADMINISTRATION Corp reports 20.81% increase in ownership of MPC / Marathon Petroleum Corporation

On May 15, 2026 - OMERS ADMINISTRATION Corp filed a 13F-HR form disclosing ownership of 29,191 shares of Marathon Petroleum Corporation (MX:MPC) valued at $7,127,858 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 24,162 shares of Marathon Petroleum Corporation. This represents a change in shares of 20.81% 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 29,191 5,029 20.81 7,128 81.39 0.0458
2026-02-13 2025-12-31 13F MARATHON PETE COM 56585A102 24,162 10,723 79.79 3,929 51.70 0.0280
2025-11-14 2025-09-30 13F MARATHON PETE COM 56585A102 13,439 -3,054 -18.52 2,590 -5.44 0.0186
2025-08-13 2025-06-30 13F MARATHON PETE COM 56585A102 16,493 -9,110 -35.58 2,740 -26.57 0.0215
2025-05-14 2025-03-31 13F MARATHON PETE COM 56585A102 25,603 9,886 62.90 3,730 70.16 0.0326
2025-02-14 2024-12-31 13F MARATHON PETE COM 56585A102 15,717 2,522 19.11 2,193 2.00 0.0192
2024-11-13 2024-09-30 13F MARATHON PETE COM 56585A102 13,195 -9,100 -40.82 2,150 -44.43 0.0198
2024-08-13 2024-06-30 13F MARATHON PETE COM 56585A102 22,295 22,295 3,868 0.0372
2024-05-14 2024-03-31 13F MARATHON PETE COM 56585A102 0 -21,300 -100.00 0 -100.00
2024-02-13 2023-12-31 13F MARATHON PETE COM 56585A102 21,300 4,600 27.54 3,160 25.05 0.0399
2023-11-13 2023-09-30 13F MARATHON PETE COM 56585A102 16,700 16,700 2,527 0.0381
2020-02-14 2019-12-31 13F MARATHON PETE COM 56585A102 0 -17,100 -100.00 0 -100.00
2019-11-12 2019-09-30 13F MARATHON PETE COM 56585A102 17,100 17,100 1,039 0.0104
2019-02-14 2018-12-31 13F MARATHON PETE COM 56585A102 0 -81,000 -100.00 0 -100.00
2018-11-14 2018-09-30 13F MARATHON PETE COM 56585A102 81,000 -22,000 -21.36 6,478 -10.35 0.0620
2018-08-09 2018-06-30 13F MARATHON PETE COM 56585A102 103,000 103,000 7,226 0.0667
2017-11-13 2017-09-30 13F MARATHON PETE COM 56585A102 0 -53,000 -100.00 0 -100.00
2017-08-08 2017-06-30 13F MARATHON PETE COM 56585A102 53,000 41,000 341.67 2,773 357.59 0.0350
2017-05-10 2017-03-31 13F MARATHON PETE COM 56585A102 12,000 0 0.00 606 0.33 0.0081
2017-02-09 2016-12-31 13F MARATHON PETE COM 56585A102 12,000 0 0.00 604 24.02 0.0112
2016-11-14 2016-09-30 13F MARATHON PETE COM 56585A102 12,000 -138,600 -92.03 487 -91.48 0.0087
2016-08-11 2016-06-30 13F MARATHON PETE COM 56585A102 150,600 -400 -0.26 5,717 1.83 0.1177
2016-05-12 2016-03-31 13F MARATHON PETE COM 56585A102 151,000 70,900 88.51 5,614 35.21 0.1245
2016-02-11 2015-12-31 13F MARATHON PETE COM 56585A102 80,100 -58,800 -42.33 4,152 -35.48 0.1073
2015-11-12 2015-09-30 13F MARATHON PETE COM 56585A102 138,900 15,300 12.38 6,435 -0.48 0.1876
2015-08-11 2015-06-30 13F MARATHON PETE COM 56585A102 123,600 74,000 149.19 6,466 27.31 0.2568
2015-05-12 2015-03-31 13F MARATHON PETE COM 56585A102 49,600 20,600 71.03 5,079 94.00 0.1905
2015-02-11 2014-12-31 13F MARATHON PETE COM 56585A102 29,000 -1,600 -5.23 2,618 1.04 0.0792
2014-11-10 2014-09-30 13F MARATHON PETE COM 56585A102 30,600 24,500 401.64 2,591 387.95 0.0772
2014-05-08 2014-03-31 13F MARATHON PETE COM 56585A102 6,100 -37,800 -86.10 531 -86.81 0.0172
2014-02-13 2013-12-31 13F MARATHON PETE COM 56585A102 43,900 -31,700 -41.93 4,027 -17.19 0.1479
2013-11-14 2013-09-30 13F MARATHON PETE COM 56585A102 75,600 7,600 11.18 4,863 0.64 0.4597
2013-08-13 2013-06-30 13F MARATHON PETE COM 56585A102 68,000 68,000 4,832 0.4510
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.