MPLX LP - Limited Partnership
US ˙ NYSE ˙ US55336V1008

SecurityMPLX / MPLX LP - Limited Partnership
InstitutionD.a. Davidson & Co.
Latest Disclosed Ownership28,501 shares
Latest Disclosed Value $ 1,626,574
D.a. Davidson & Co. reports 2.35% increase in ownership of MPLX / MPLX LP - Limited Partnership

On May 5, 2026 - D.a. Davidson & Co. filed a 13F-HR form disclosing ownership of 28,501 shares of MPLX LP - Limited Partnership (US:MPLX) valued at $1,626,552 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 29, 2026 disclosing 27,847 shares of MPLX LP - Limited Partnership. This represents a change in shares of 2.35% during the quarter. The current value of the position is $1,609,451 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)
2026-05-05 2026-03-31 13F MPLX COM UNIT REP LTD 55336V100 28,501 654 2.35 1,627 9.42 0.0099
2026-01-29 2025-12-31 13F MPLX COM UNIT REP LTD 55336V100 27,847 -655 -2.30 1,486 4.43 0.0091
2025-10-22 2025-09-30 13F MPLX COM UNIT REP LTD 55336V100 28,502 -398 -1.38 1,424 -4.37 0.0091
2025-07-30 2025-06-30 13F MPLX COM UNIT REP LTD 55336V100 28,900 1,743 6.42 1,489 2.41 0.0105
2025-04-28 2025-03-31 13F MPLX COM UNIT REP LTD 55336V100 27,157 -705 -2.53 1,453 9.00 0.0117
2025-01-31 2024-12-31 13F MPLX COM UNIT REP LTD 55336V100 27,862 2,462 9.69 1,333 18.07 0.0109
2024-11-13 2024-09-30 13F MPLX COM UNIT REP LTD 55336V100 25,400 862 3.51 1,129 8.04 0.0093
2024-08-01 2024-06-30 13F MPLX COM UNIT REP LTD 55336V100 24,538 3,231 15.16 1,045 18.08 0.0093
2024-05-13 2024-03-31 13F MPLX COM UNIT REP LTD 55336V100 21,307 2,297 12.08 886 26.79 0.0080
2024-02-09 2023-12-31 13F MPLX COM UNIT REP LTD 55336V100 19,010 -51 -0.27 698 2.95 0.0068
2023-11-08 2023-09-30 13F MPLX COM UNIT REP LTD 55336V100 19,061 415 2.23 678 7.28 0.0074
2023-08-11 2023-06-30 13F MPLX COM UNIT REP LTD 55336V100 18,646 -12,351 -39.85 633 -40.77 0.0067
2023-04-25 2023-03-31 13F MPLX COM UNIT REP LTD 55336V100 30,997 10,362 50.22 1,068 57.61 0.0120
2023-02-03 2022-12-31 13F MPLX COM UNIT REP LTD 55336V100 20,635 37 0.18 678 9.55 0.0080
2022-11-07 2022-09-30 13F MPLX COM UNIT REP LTD 55336V100 20,598 388 1.92 618 4.92 0.0081
2022-07-28 2022-06-30 13F MPLX COM UNIT REP LTD 55336V100 20,210 5,527 37.64 589 20.94 0.0074
2022-05-12 2022-03-31 13F MPLX COM UNIT REP LTD 55336V100 14,683 2,662 22.14 487 36.80 0.0053
2022-01-31 2021-12-31 13F MPLX COM UNIT REP LTD 55336V100 12,021 599 5.24 356 9.54 0.0038
2021-11-15 2021-09-30 13F MPLX COM UNIT REP LTD 55336V100 11,422 11,422 325 0.0038
2017-11-08 2017-09-30 13F MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 0 -5,230 -100.00 0 -100.00
2017-08-11 2017-06-30 13F MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 5,230 0 0.00 174 -7.45 0.0039
2017-05-12 2017-03-31 13F MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 5,230 265 5.34 188 9.94 0.0046
2017-02-15 2016-12-31 13F MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 4,965 305 6.55 171 8.92 0.0039
2016-11-18 2016-09-30 13F/A-1 MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 4,660 300 6.88 157 7.53 0.0039
2016-11-14 2016-09-30 13F MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 4,660 157
2016-08-13 2016-06-30 13F MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 4,360 0 0.00 146 13.18 0.0043
2016-05-13 2016-03-31 13F MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 4,360 -763 -14.89 129 -35.82 0.0040
2016-02-12 2015-12-31 13F MPLX LTD PRTNESHIP REPSTG LTD PARTNER INT PRTNRSP 55336V100 5,123 5,123 201 0.0065
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.