Marathon Petroleum Corporation
MX ˙ BMV ˙ US56585A1025
SecurityMX:MPC / Marathon Petroleum Corporation
InstitutionNorth Star Asset Management Inc
Latest Disclosed Ownership1,508 shares
Latest Disclosed Value $ 368,223
North Star Asset Management Inc reports 3.21% decrease in ownership of MPC / Marathon Petroleum Corporation

On May 6, 2026 - North Star Asset Management Inc filed a 13F-HR form disclosing ownership of 1,508 shares of Marathon Petroleum Corporation (MX:MPC) valued at $368,223 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 9, 2026 disclosing 1,558 shares of Marathon Petroleum Corporation. This represents a change in shares of -3.21% 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)
2026-05-06 2026-03-31 13F MARATHON PETROLEUM COM 56585A102 1,508 -50 -3.21 368 45.45 0.0096
2026-02-09 2025-12-31 13F MARATHON PETROLEUM COM 56585A102 1,558 0 0.00 253 -15.67 0.0102
2025-11-10 2025-09-30 13F MARATHON PETROLEUM COM 56585A102 1,558 -50 -3.11 300 12.36 0.0122
2025-08-12 2025-06-30 13F MARATHON PETROLEUM COM 56585A102 1,608 0 0.00 267 14.10 0.0113
2025-05-08 2025-03-31 13F MARATHON PETROLEUM COM 56585A102 1,608 1,608 234 0.0107
2025-02-19 2024-12-31 13F MARATHON PETROLEUM COM 56585A102 0 -1,777 -100.00 0 -100.00
2024-11-14 2024-09-30 13F MARATHON PETROLEUM COM 56585A102 1,777 146 8.95 289 2.48 0.0130
2024-08-05 2024-06-30 13F MARATHON PETROLEUM COM 56585A102 1,631 116 7.66 283 -7.54 0.0134
2024-05-08 2024-03-31 13F MARATHON PETROLEUM COM 56585A102 1,515 -824 -35.23 305 -12.10 0.0144
2024-02-01 2023-12-31 13F MARATHON PETROLEUM COM 56585A102 2,339 -2,660 -53.21 347 -54.10 0.0178
2023-10-26 2023-09-30 13F MARATHON PETROLEUM COM 56585A102 4,999 -90 -1.77 757 27.49 0.0434
2023-08-09 2023-06-30 13F MARATHON PETROLEUM COM 56585A102 5,089 0 0.00 593 -13.56 0.0327
2023-05-10 2023-03-31 13F MARATHON PETROLEUM COM 56585A102 5,089 -179 -3.40 686 11.91 0.0403
2023-03-06 2022-12-31 13F MARATHON PETROLEUM COM 56585A102 5,268 5,268 613 0.0381
2020-04-24 2020-03-31 13F MARATHON PETROLEUM COM 56585A102 0 -4,817 -100.00 0 -100.00
2020-02-06 2019-12-31 13F MARATHON PETROLEUM COM 56585A102 4,817 0 0.00 290 -1.02 0.0208
2019-10-25 2019-09-30 13F MARATHON PETROLEUM COM 56585A102 4,817 0 0.00 293 8.92 0.0230
2019-08-12 2019-06-30 13F MARATHON PETROLEUM COM 56585A102 4,817 579 13.66 269 5.91 0.0210
2019-04-26 2019-03-31 13F MARATHON PETROLEUM COM 56585A102 4,238 0 0.00 254 1.60 0.0206
2019-01-29 2018-12-31 13F MARATHON PETROLEUM COM 56585A102 4,238 466 12.35 250 -17.22 0.0237
2018-10-29 2018-09-30 13F MARATHON PETROLEUM COM 56585A102 3,772 -1,000 -20.96 302 -9.85 0.0242
2018-08-10 2018-06-30 13F MARATHON PETROLEUM COM 56585A102 4,772 0 0.00 335 -4.01 0.0287
2018-04-27 2018-03-31 13F MARATHON PETROLEUM COM 56585A102 4,772 0 0.00 349 10.79 0.0314
2018-02-01 2017-12-31 13F MARATHON PETROLEUM COM 56585A102 4,772 0 0.00 315 17.54 0.0283
2017-10-25 2017-09-30 13F/A-1 MARATHON PETROLEUM COM 56585A102 4,772 0 0.00 268 7.20 0.0266
2017-10-25 2017-09-30 13F MARATHON PETROLEUM COM 56585A102 4,972 200 251
2017-08-16 2017-06-30 13F MARATHON PETROLEUM COM 56585A102 4,772 -200 -4.02 250 -0.40 0.0254
2017-05-18 2017-03-31 13F MARATHON PETROLEUM COM 56585A102 4,972 4,972 251 0.0265
2016-05-05 2016-03-31 13F MARATHON PETROLEUM COM 56585A102 0 -4,012 -100.00 0 -100.00
2016-01-28 2015-12-31 13F MARATHON PETROLEUM COM 56585A102 4,012 4,012 0.00 208 0.0250
2015-10-28 2015-09-30 13F MARATHON PETROLEUM COM 56585A102 0 -4,112 -100.00 0 -100.00
2015-07-30 2015-06-30 13F MARATHON PETROLEUM COM 56585A102 4,112 2,056 100.00 215 1.90 0.0244
2015-05-15 2015-03-31 13F MARATHON PETROLEUM COM 56585A102 2,056 -311 -13.14 211 -2.76 0.0239
2014-02-07 2013-12-31 13F MARATHON PETROLEUM COM 56585A102 2,367 -475 -16.71 217 7.43 0.0263
2013-08-06 2013-06-30 13F MARATHON PETROLEUM COM 56585A102 2,842 2,842 202 0.0282
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.