Marathon Petroleum Corporation
MX ˙ BMV ˙ US56585A1025
SecurityMX:MPC / Marathon Petroleum Corporation
InstitutionHartford Financial Management Inc.
Latest Disclosed Ownership8,239 shares
Latest Disclosed Value $ 2,011,696
Hartford Financial Management Inc. reports 6.07% decrease in ownership of MPC / Marathon Petroleum Corporation

On April 15, 2026 - Hartford Financial Management Inc. filed a 13F-HR form disclosing ownership of 8,239 shares of Marathon Petroleum Corporation (MX:MPC) valued at $2,011,696 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 21, 2026 disclosing 8,771 shares of Marathon Petroleum Corporation. This represents a change in shares of -6.07% 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)
2026-04-15 2026-03-31 13F MARATHON PETE COM 56585A102 8,239 -532 -6.07 2,012 41.02 0.5126
2026-01-21 2025-12-31 13F MARATHON PETE COM 56585A102 8,771 -30 -0.34 1,426 -15.92 0.3706
2025-10-28 2025-09-30 13F MARATHON PETE COM 56585A102 8,801 3 0.03 1,696 16.08 0.4492
2025-07-31 2025-06-30 13F MARATHON PETE COM 56585A102 8,798 3 0.03 1,461 14.05 0.3996
2025-04-21 2025-03-31 13F MARATHON PETE COM 56585A102 8,795 3 0.03 1,281 4.49 0.2645
2025-01-23 2024-12-31 13F MARATHON PETE COM 56585A102 8,792 -175 -1.95 1,226 -16.03 0.2512
2024-10-28 2024-09-30 13F MARATHON PETE COM 56585A102 8,967 -47 -0.52 1,461 -6.59 0.2986
2024-08-09 2024-06-30 13F MARATHON PETE COM 56585A102 9,014 2 0.02 1,564 -13.88 0.3354
2024-04-24 2024-03-31 13F MARATHON PETE COM 56585A102 9,012 2 0.02 1,816 35.85 0.3834
2024-01-29 2023-12-31 13F MARATHON PETE COM 56585A102 9,010 -1 -0.01 1,337 -1.98 0.3028
2023-10-24 2023-09-30 13F MARATHON PETE COM 56585A102 9,011 2 0.02 1,364 29.81 0.3482
2023-07-27 2023-06-30 13F MARATHON PETE COM 56585A102 9,009 3 0.03 1,050 -13.51 0.2596
2023-04-25 2023-03-31 13F MARATHON PETE COM 56585A102 9,006 -50 -0.55 1,214 15.29 0.3140
2023-02-01 2022-12-31 13F MARATHON PETE COM 56585A102 9,056 -347 -3.69 1,054 12.74 0.2787
2022-10-25 2022-09-30 13F MARATHON PETE COM 56585A102 9,403 -10 -0.11 934 20.67 0.2745
2022-07-21 2022-06-30 13F MARATHON PETE COM 56585A102 9,413 3 0.03 774 -3.85 0.2146
2022-05-05 2022-03-31 13F MARATHON PETE COM 56585A102 9,410 3 0.03 805 33.72 0.1942
2022-01-27 2021-12-31 13F MARATHON PETE COM 56585A102 9,407 -95 -1.00 602 2.56 0.1400
2021-10-29 2021-09-30 13F MARATHON PETE COM 56585A102 9,502 4 0.04 587 2.26 0.1494
2021-07-27 2021-06-30 13F MARATHON PETE COM 56585A102 9,498 4 0.04 574 12.99 0.1425
2021-04-14 2021-03-31 13F MARATHON PETE COM 56585A102 9,494 348 3.80 508 34.39 0.1260
2021-02-03 2020-12-31 13F MARATHON PETE COM 56585A102 9,146 -317 -3.35 378 35.97 0.1002
2020-10-16 2020-09-30 13F MARATHON PETE COM 56585A102 9,463 105 1.12 278 -20.57 0.0824
2020-07-23 2020-06-30 13F MARATHON PETE COM 56585A102 9,358 -24,139 -72.06 350 -55.75 0.1118
2020-05-01 2020-03-31 13F MARATHON PETE COM 56585A102 33,497 -476 -1.40 791 -61.36 0.3162
2020-01-28 2019-12-31 13F MARATHON PETE COM 56585A102 33,973 -3,084 -8.32 2,047 -9.06 0.6396
2019-10-28 2019-09-30 13F MARATHON PETE COM 56585A102 37,057 397 1.08 2,251 9.86 0.7509
2019-08-01 2019-06-30 13F MARATHON PETE COM 56585A102 36,660 -736 -1.97 2,049 -8.45 0.6839
2019-05-08 2019-03-31 13F MARATHON PETE COM 56585A102 37,396 478 1.29 2,238 2.71 0.7647
2019-02-04 2018-12-31 13F MARATHON PETE COM 56585A102 36,918 293 0.80 2,179 -25.61 0.8324
2018-11-01 2018-09-30 13F MARATHON PETE COM 56585A102 36,625 -798 -2.13 2,929 11.54 0.9919
2018-08-10 2018-06-30 13F MARATHON PETE COM 56585A102 37,423 -991 -2.58 2,626 -6.48 0.9352
2018-04-10 2018-03-31 13F Marathon Petroleum COM 56585A102 38,414 -513 -1.32 2,808 9.35 1.4217
2018-01-16 2017-12-31 13F Marathon Petroleum COM 56585A102 38,927 1 0.00 2,568 17.69 1.2602
2017-10-16 2017-09-30 13F Marathon Petroleum COM 56585A102 38,926 -100 -0.26 2,182 6.86 1.1071
2017-07-28 2017-06-30 13F Marathon Petroleum COM 56585A102 39,026 200 0.52 2,042 4.08 0.9175
2017-04-19 2017-03-31 13F Marathon Petroleum COM 56585A102 38,826 0 0.00 1,962 0.36 1.1824
2017-02-13 2016-12-31 13F Marathon Petroleum COM 56585A102 38,826 -48 -0.12 1,955 23.97 1.1588
2016-10-25 2016-09-30 13F Marathon Petroleum COM 56585A102 38,874 0 0.00 1,577 6.92 0.9579
2016-07-14 2016-06-30 13F/A-1 Marathon Petroleum COM 56585A102 38,874 2,625 7.24 1,475 9.50 0.8876
2016-07-14 2016-06-30 13F Marathon Petroleum COM 56585A102 38,874 1,475
2016-04-20 2016-03-31 13F Marathon Petroleum COM 56585A102 36,249 6,395 21.42 1,347 -12.93 0.8377
2016-01-28 2015-12-31 13F Marathon Petroleum COM 56585A102 29,854 1,600 5.66 1,547 18.18 0.9659
2015-10-28 2015-09-30 13F Marathon Petroleum COM 56585A102 28,254 -300 -1.05 1,309 -12.32 0.8745
2015-07-07 2015-06-30 13F Marathon Petroleum COM 56585A102 28,554 14,277 100.00 1,493 2.19 0.8723
2015-04-13 2015-03-31 13F Marathon Petroleum COM 56585A102 14,277 0 0.00 1,461 13.43 0.8978
2015-02-09 2014-12-31 13F Marathon Petroleum COM 56585A102 14,277 -70 -0.49 1,288 6.10 0.7936
2014-10-29 2014-09-30 13F Marathon Petroleum COM 56585A102 14,347 0 0.00 1,214 8.39 0.7275
2014-08-05 2014-06-30 13F Marathon Petroleum COM 56585A102 14,347 0 0.00 1,120 -10.26 0.6787
2014-05-07 2014-03-31 13F Marathon Petroleum COM 56585A102 14,347 0 0.00 1,248 -5.17 0.8162
2014-01-31 2013-12-31 13F Marathon Petroleum COM 56585A102 14,347 0 0.00 1,316 42.73 0.8539
2013-10-30 2013-09-30 13F Marathon Petroleum COM 56585A102 14,347 0 0.00 922 -9.52 0.6361
2013-08-15 2013-06-30 13F Marathon Petroleum COM 56585A102 14,347 14,347 1,019 0.7049
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.