MPLX LP - Limited Partnership
US ˙ NYSE ˙ US55336V1008

SecurityMPLX / MPLX LP - Limited Partnership
InstitutionIng Groep Nv
Latest Disclosed Ownership1,768,200 shares
Latest Disclosed Value $ 100,911,174
Ing Groep Nv reports 39.11% decrease in ownership of MPLX / MPLX LP - Limited Partnership

On May 11, 2026 - Ing Groep Nv filed a 13F-HR form disclosing ownership of 1,768,200 shares of MPLX LP - Limited Partnership (US:MPLX) valued at $100,911,174 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 2,903,800 shares of MPLX LP - Limited Partnership. This represents a change in shares of -39.11% during the quarter. The current value of the position is $97,710,732 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)
2026-05-11 2026-03-31 13F MPLX COM UNIT REP LTD 55336V100 1,768,200 -1,135,600 -39.11 100,911 -34.89 0.6171
2026-02-11 2025-12-31 13F MPLX COM UNIT REP LTD 55336V100 2,903,800 -1,400,500 -32.54 154,976 -27.92 0.9347
2025-11-06 2025-09-30 13F MPLX COM UNIT REP LTD 55336V100 4,304,300 -258,200 -5.66 215,000 -8.52 1.1631
2025-08-06 2025-06-30 13F MPLX COM UNIT REP LTD 55336V100 4,562,500 15,000 0.33 235,014 -3.44 1.4299
2025-05-09 2025-03-31 13F MPLX COM UNIT REP LTD 55336V100 4,547,500 -78,100 -1.69 243,382 9.94 1.6877
2025-02-03 2024-12-31 13F MPLX COM UNIT REP LTD 55336V100 4,625,600 -2,002,800 -30.22 221,381 -24.88 1.4918
2024-11-06 2024-09-30 13F MPLX COM UNIT REP LTD 55336V100 6,628,400 2,725,000 69.81 294,699 77.27 1.7128
2024-08-13 2024-06-30 13F MPLX COM UNIT REP LTD 55336V100 3,903,400 735,000 23.20 166,246 26.25 0.9861
2024-05-10 2024-03-31 13F MPLX COM UNIT REP LTD 55336V100 3,168,400 427,900 15.61 131,679 30.85 0.9027
2024-02-08 2023-12-31 13F MPLX COM UNIT REP LTD 55336V100 2,740,500 480,000 21.23 100,631 25.16 0.8083
2023-10-27 2023-09-30 13F MPLX COM UNIT REP LTD 55336V100 2,260,500 0 0.00 80,406 4.80 0.7094
2023-08-07 2023-06-30 13F MPLX COM UNIT REP LTD 55336V100 2,260,500 0 0.00 76,721 -1.48 0.5818
2023-05-09 2023-03-31 13F MPLX COM UNIT REP LTD 55336V100 2,260,500 0 0.00 77,874 4.90 0.7560
2023-02-13 2022-12-31 13F MPLX COM UNIT REP LTD 55336V100 2,260,500 0 0.00 74,235 9.43 0.7451
2022-11-14 2022-09-30 13F MPLX COM UNIT REP LTD 55336V100 2,260,500 0 0.00 67,838 2.95 1.1353
2022-08-08 2022-06-30 13F MPLX COM UNIT REP LTD 55336V100 2,260,500 -1,401,000 -38.26 65,894 -45.76 0.7619
2022-05-13 2022-03-31 13F MPLX COM UNIT REP LTD 55336V100 3,661,500 929,000 34.00 121,489 50.26 1.2248
2022-02-11 2021-12-31 13F MPLX COM UNIT REP LTD 55336V100 2,732,500 -351,500 -11.40 80,855 -7.91 0.7232
2021-11-02 2021-09-30 13F MPLX COM UNIT REP LTD 55336V100 3,084,000 261,000 9.25 87,801 5.04 1.1271
2021-08-13 2021-06-30 13F MPLX COM UNIT REP LTD 55336V100 2,823,000 137,000 5.10 83,589 21.42 1.3322
2021-05-12 2021-03-31 13F MPLX COM UNIT REP LTD 55336V100 2,686,000 -1,547,751 -36.56 68,842 -24.89 1.4263
2021-02-11 2020-12-31 13F MPLX COM UNIT REP LTD 55336V100 4,233,751 -366,949 -7.98 91,661 26.58 2.0458
2020-11-12 2020-09-30 13F MPLX COM UNIT REP LTD 55336V100 4,600,700 1,321,000 40.28 72,415 27.78 2.9832
2020-08-13 2020-06-30 13F MPLX COM UNIT REP LTD 55336V100 3,279,700 2,070,000 171.12 56,673 303.17 2.4409
2020-05-06 2020-03-31 13F MPLX COM UNIT REP LTD 55336V100 1,209,700 1,000,000 476.87 14,057 163.29 0.6013
2020-02-10 2019-12-31 13F MPLX COM UNIT REP LTD 55336V100 209,700 -304,705 -59.23 5,339 -62.94 0.1625
2019-11-08 2019-09-30 13F MPLX COM UNIT REP LTD 55336V100 514,405 -83,373 -13.95 14,408 -25.12 0.3659
2019-08-12 2019-06-30 13F MPLX COM UNIT REP LTD 55336V100 597,778 -331,700 -35.69 19,242 -37.06 0.3353
2019-05-13 2019-03-31 13F MPLX COM UNIT REP LTD 55336V100 929,478 669,778 257.90 30,571 288.50 0.6616
2019-02-13 2018-12-31 13F MPLX COM UNIT REP LTD 55336V100 259,700 259,700 7,869 0.1704
2018-05-07 2018-03-31 13F MPLX COM UNIT REP LTD 55336V100 0 -340,000 -100.00 0 -100.00
2018-02-06 2017-12-31 13F MPLX COM UNIT REP LTD 55336V100 340,000 -2,784,100 -89.12 12,060 -88.97 0.2011
2017-11-08 2017-09-30 13F MPLX COM UNIT REP LTD 55336V100 3,124,100 749,100 31.54 109,375 37.88 2.1073
2017-07-25 2017-06-30 13F MPLX COM UNIT REP LTD 55336V100 2,375,000 49,300 2.12 79,325 -5.47 1.5195
2017-05-01 2017-03-31 13F MPLX COM UNIT REP LTD 55336V100 2,325,700 -30,600 -1.30 83,911 4.65 1.5214
2017-02-06 2016-12-31 13F MPLX COM UNIT REP LTD 55336V100 2,356,300 -3,538,821 -60.03 80,185 -58.53 1.5047
2016-11-14 2016-09-30 13F MPLX COM UNIT REP LTD 55336V100 5,895,121 656,439 12.53 193,360 9.85 2.3314
2016-07-27 2016-06-30 13F MPLX COM UNIT REP LTD 55336V100 5,238,682 1,375,800 35.62 176,020 53.48 2.3666
2016-05-12 2016-03-31 13F MPLX COM UNIT REP LTD 55336V100 3,862,882 1,587,053 69.74 114,689 28.13 1.4297
2016-02-12 2015-12-31 13F MPLX COM UNIT REP LTD 55336V100 2,275,829 2,205,829 3,151.18 89,508 3,241.10 0.5385
2015-12-09 2015-09-30 13F/A-1 MPLX COM UNIT REP LTD 55336V100 70,000 -196,670 -73.75 2,679 -85.98 0.0185
2015-11-10 2015-09-30 13F MPLX COM UNIT REP LTD 55336V100 70,000 2,679
2015-08-10 2015-06-30 13F MPLX COM UNIT REP LTD 55336V100 266,670 11,000 4.30 19,112 2.15 0.1035
2015-05-14 2015-03-31 13F MPLX COM UNIT REP LTD 55336V100 255,670 255,670 18,710 0.0940
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.