MPLX LP - 有限合夥企業
US ˙ NYSE ˙ US55336V1008

SecurityMPLX / MPLX LP - Limited Partnership
InstitutionUBS Group AG
Latest Disclosed Ownership5,233,512 shares
Latest Disclosed Value $ 298,676,529
UBS Group AG ownership in MPLX / MPLX LP - Limited Partnership

On May 5, 2026 - UBS Group AG filed a 13F-HR form disclosing ownership of 5,233,512 shares of MPLX LP - Limited Partnership (US:MPLX) valued at $298,676,530 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 29, 2026 disclosing 5,304,746 shares of MPLX LP - Limited Partnership. This represents a change in shares of -1.34% during the quarter. The current value of the position is $295,536,423 USD.

UBS Group AG has a history of taking positions in derivatives of the underlying security (MPLX) in the form of stock options. The firm currently holds call options representing 0 of underlying shares valued at $0 USD and put options representing 0 of underlying shares valued at $0 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MPLX / MPLX LP - Limited Partnership Historical Put/Call Ratio
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 5,233,512 -71,234 -1.34 298,677 5.50 0.0084
2026-01-29 2025-12-31 13F MPLX COM UNIT REP LTD 55336V100 5,304,746 38,283 0.73 283,114 7.62 0.0082
2025-11-13 2025-09-30 13F MPLX COM UNIT REP LTD 55336V100 5,266,463 -1,542,786 -22.66 263,060 -25.00 0.0412
2025-08-14 2025-06-30 13F MPLX COM UNIT REP LTD 55336V100 6,809,249 869,016 14.63 350,744 10.32 0.0607
2025-05-13 2025-03-31 13F MPLX COM UNIT REP LTD 55336V100 5,940,233 215,906 3.77 317,921 16.04 0.0584
2025-02-14 2024-12-31 13F MPLX COM UNIT REP LTD 55336V100 5,724,327 104,335 1.86 273,966 9.65 0.0506
2024-11-14 2024-09-30 13F MPLX COM UNIT REP LTD 55336V100 5,619,992 -120,304 -2.10 249,865 2.20 0.0544
2024-08-14 2024-06-30 13F MPLX COM UNIT REP LTD 55336V100 5,740,296 -649,693 -10.17 244,479 -7.94 0.0604
2024-05-13 2024-03-31 13F MPLX COM UNIT REP LTD 55336V100 6,389,989 648,977 11.30 265,568 25.98 0.0661
2024-02-09 2023-12-31 13F MPLX COM UNIT REP LTD 55336V100 5,741,012 -128,424 -2.19 210,810 0.97 0.0631
2023-11-09 2023-09-30 13F MPLX COM UNIT REP LTD 55336V100 5,869,436 639,199 12.22 208,776 17.61 0.0720
2023-08-11 2023-06-30 13F MPLX COM UNIT REP LTD 55336V100 5,230,237 -402,537 -7.15 177,514 -8.52 0.0599
2023-05-12 2023-03-31 13F MPLX COM UNIT REP LTD 55336V100 5,632,774 347,268 6.57 194,049 11.79 0.0709
2023-02-08 2022-12-31 13F MPLX COM UNIT REP LTD 55336V100 5,285,506 -938,460 -15.08 173,576 -7.07 0.0648
2022-11-10 2022-09-30 13F MPLX COM UNIT REP LTD 55336V100 6,223,966 425,425 7.34 186,781 10.50 0.0819
2022-08-10 2022-06-30 13F MPLX COM UNIT REP LTD 55336V100 5,798,541 529,595 10.05 169,027 -3.32 0.0694
2022-05-16 2022-03-31 13F MPLX COM UNIT REP LTD 55336V100 5,268,946 430,063 8.89 174,824 22.10 0.0583
2022-02-14 2021-12-31 13F MPLX COM UNIT REP LTD 55336V100 4,838,883 -13,213 -0.27 143,183 3.65 0.0410
2021-11-15 2021-09-30 13F MPLX COM UNIT REP LTD 55336V100 4,852,096 -241,654 -4.74 138,139 -8.41 0.0435
2021-08-13 2021-06-30 13F MPLX COM UNIT REP LTD 55336V100 5,093,750 -702,210 -12.12 150,826 1.53 0.0486
2021-05-12 2021-03-31 13F MPLX COM UNIT REP LTD 55336V100 5,795,960 -1,782,838 -23.52 148,550 -9.47 0.0493
2021-02-11 2020-12-31 13F MPLX COM UNIT REP LTD 55336V100 7,578,798 -1,189,740 -13.57 164,081 18.88 0.0555
2020-11-12 2020-09-30 13F MPLX COM UNIT REP LTD 55336V100 8,768,538 -1,755,449 -16.68 138,017 -24.11 0.0520
2020-07-31 2020-06-30 13F MPLX COM UNIT REP LTD 55336V100 10,523,987 -824,859 -7.27 181,855 37.90 0.0768
2020-05-01 2020-03-31 13F MPLX COM UNIT REP LTD 55336V100 11,348,846 2,130,708 23.11 131,873 -43.81 0.0621
2020-02-14 2019-12-31 13F MPLX COM UNIT REP LTD 55336V100 9,218,138 -3,227,083 -25.93 234,694 -32.67 0.0817
2019-11-14 2019-09-30 13F MPLX COM UNIT REP LTD 55336V100 12,445,221 1,895,408 17.97 348,591 2.65 0.1342
2019-08-14 2019-06-30 13F MPLX COM UNIT REP LTD 55336V100 10,549,813 78,614 0.75 339,599 -1.39 0.1308
2019-05-14 2019-03-31 13F MPLX COM UNIT REP LTD 55336V100 10,471,199 827,547 8.58 344,398 17.86 0.1423
2019-02-14 2018-12-31 13F MPLX COM UNIT REP LTD 55336V100 9,643,652 1,733,287 21.91 292,203 6.51 0.1325
2018-11-14 2018-09-30 13F MPLX COM UNIT REP LTD 55336V100 7,910,365 2,061,815 35.25 274,331 37.39 0.1087
2018-08-14 2018-06-30 13F MPLX COM UNIT REP LTD 55336V100 5,848,550 -1,779,370 -23.33 199,670 -20.77 0.0865
2018-05-15 2018-03-31 13F MPLX COM UNIT REP LTD 55336V100 7,627,920 3,141,784 70.03 252,027 58.39 0.1088
2018-02-14 2017-12-31 13F MPLX COM UNIT REP LTD 55336V100 4,486,136 -641 -0.01 159,123 1.30 0.0654
2017-11-14 2017-09-30 13F MPLX COM UNIT REP LTD 55336V100 4,486,777 -904,027 -16.77 157,082 -12.76 0.0727
2017-11-14 2017-06-30 13F/A-1 MPLX COM UNIT REP LTD 55336V100 5,390,804 -1,349,002 -20.02 180,053 -25.96 0.0932
2017-08-14 2017-06-30 13F MPLX COM UNIT REP LTD 55336V100 5,390,804 -1,349,002 180,053
2017-11-14 2017-03-31 13F/A-1 MPLX COM UNIT REP LTD 55336V100 6,739,806 -338,784 -4.79 243,173 -0.77 0.1327
2017-05-12 2017-03-31 13F MPLX COM UNIT REP LTD 55336V100 6,739,806 -338,784 243,173
2017-02-14 2016-12-31 13F MPLX COM UNIT REP LTD 55336V100 7,078,590 2,948,111 71.37 245,061 75.22 0.1353
2016-11-14 2016-09-30 13F MPLX COM UNIT REP LTD 55336V100 4,130,479 1,313,635 46.63 139,858 47.64 0.0834
2016-08-12 2016-06-30 13F MPLX COM UNIT REP LTD 55336V100 2,816,844 -89,633 -3.08 94,731 9.78 0.0595
2016-05-12 2016-03-31 13F MPLX COM UNIT REP LTD 55336V100 2,906,477 -9,346,190 -76.28 86,293 -82.09 0.0578
2016-02-16 2015-12-31 13F MPLX COM UNIT REP LTD 55336V100 12,252,667 11,954,698 4,012.06 481,898 4,132.74 0.3128
2015-11-13 2015-09-30 13F MPLX COM UNIT REP LTD 55336V100 297,969 -779 -0.26 11,385 -46.61 0.0081
2015-08-14 2015-06-30 13F MPLX COM UNIT REP LTD 55336V100 298,748 -50,307 -14.41 21,324 -16.61 0.0142
2015-05-14 2015-03-31 13F MPLX COM UNIT REP LTD 55336V100 349,055 61,869 21.54 25,572 21.17 0.0177
2015-02-17 2014-12-31 13F MPLX COM UNIT REP LTD 55336V100 287,186 287,186 21,105 0.0148
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2025-08-14 2025-06-30 13F MPLX COM UNIT REP LTD Call 0 -100.00 0 -100.00 n/a n/a n/a
2025-05-13 2025-03-31 13F MPLX COM UNIT REP LTD Call 258,300 -32.72 13,824 -24.76 n/a n/a n/a
2025-02-14 2024-12-31 13F MPLX COM UNIT REP LTD Call 383,900 18,373 n/a n/a n/a
2023-05-12 2023-03-31 13F MPLX COM UNIT REP LTD Call 0 -100.00 0 -100.00 n/a n/a n/a
2023-02-08 2022-12-31 13F MPLX COM UNIT REP LTD Call 2,500 82 n/a n/a n/a
2021-08-13 2021-06-30 13F MPLX COM UNIT REP LTD Call 0 -100.00 0 -100.00 n/a n/a n/a
2021-05-12 2021-03-31 13F MPLX COM UNIT REP LTD Call 350,000 8,971 n/a n/a n/a
2019-11-14 2019-09-30 13F MPLX COM UNIT REP LTD Call 0 -100.00 0 -100.00 n/a n/a n/a
2019-08-14 2019-06-30 13F MPLX COM UNIT REP LTD Call 330,000 0.00 10,623 -2.13 n/a n/a n/a
2019-05-14 2019-03-31 13F MPLX COM UNIT REP LTD Call 330,000 10,854 n/a n/a n/a
2017-11-14 2017-03-31 13F/A MPLX COM UNIT REP LTD Call 0 -100.00 0 -100.00 n/a n/a n/a
2017-02-14 2016-12-31 13F MPLX COM UNIT REP LTD Call 16,000 554 n/a n/a n/a
2015-08-14 2015-06-30 13F MPLX COM UNIT REP LTD Call 0 -100.00 0 -100.00 n/a n/a n/a
2015-05-14 2015-03-31 13F MPLX COM UNIT REP LTD Call 15,000 1,099 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2020-07-31 2020-06-30 13F MPLX COM UNIT REP LTD Put 0 -100.00 0 -100.00 n/a n/a n/a
2020-05-01 2020-03-31 13F MPLX COM UNIT REP LTD Put 10,000 33.33 116 -39.27 n/a n/a n/a
2020-02-14 2019-12-31 13F MPLX COM UNIT REP LTD Put 7,500 -69.88 191 -72.60 n/a n/a n/a
2019-11-14 2019-09-30 13F MPLX COM UNIT REP LTD Put 24,900 -92.62 697 -93.58 n/a n/a n/a
2019-08-14 2019-06-30 13F MPLX COM UNIT REP LTD Put 337,500 -0.94 10,864 -3.05 n/a n/a n/a
2019-05-14 2019-03-31 13F MPLX COM UNIT REP LTD Put 340,700 1,824.86 11,206 1,990.67 n/a n/a n/a
2019-02-14 2018-12-31 13F MPLX COM UNIT REP LTD Put 17,700 536 n/a n/a n/a
2018-05-15 2018-03-31 13F MPLX COM UNIT REP LTD Put 0 -100.00 0 -100.00 n/a n/a n/a
2018-02-14 2017-12-31 13F MPLX COM UNIT REP LTD Put 117,300 -80.92 4,161 -80.67 n/a n/a n/a
2017-11-14 2017-09-30 13F MPLX COM UNIT REP LTD Put 614,800 -48.80 21,524 -46.33 n/a n/a n/a
2017-11-14 2017-06-30 13F/A MPLX COM UNIT REP LTD Put 1,200,700 29.23 40,103 19.63 n/a n/a n/a
2017-08-14 2017-06-30 13F MPLX COM UNIT REP LTD Put 1,200,700 40,103 n/a n/a n/a
2017-11-14 2017-03-31 13F/A MPLX COM UNIT REP LTD Put 929,100 28.70 33,522 34.13 n/a n/a n/a
2017-05-12 2017-03-31 13F MPLX COM UNIT REP LTD Put 929,100 33,522 n/a n/a n/a
2017-02-14 2016-12-31 13F MPLX COM UNIT REP LTD Put 721,900 890.26 24,992 912.64 n/a n/a n/a
2016-11-14 2016-09-30 13F MPLX COM UNIT REP LTD Put 72,900 2,468 n/a n/a n/a
2016-05-12 2016-03-31 13F MPLX COM UNIT REP LTD Put 0 -100.00 0 -100.00 n/a n/a n/a
2016-02-16 2015-12-31 13F MPLX COM UNIT REP LTD Put 113,000 4,444 n/a n/a n/a
2015-08-14 2015-06-30 13F MPLX COM UNIT REP LTD Put 0 -100.00 0 -100.00 n/a n/a n/a
2015-05-14 2015-03-31 13F MPLX COM UNIT REP LTD Put 68,900 5,048 n/a n/a n/a
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.