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Public ownership evidence

MPLX LP (MPLX) Ownership Disclosures

Read MPLX insider transactions, institutional 13F filings and Congressional disclosures with report dates, public availability and original receipts.

As of 2026-11-07T14:03:26.246Z

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2026-11-032026-11-01Niemeyer Bruce LA1,276.71Not reported

First displayed source row from Recent Form 4 activity. The full bounded history and coverage notes remain below.

The displayed observation date is 2026-11-01 and its public availability date is 2026-11-03. Subtracting those calendar dates gives 2 days of disclosure lag. Historical public research can use the record from the availability date, rather than backdating knowledge to the observation date. The calendar-day difference does not assert an intraday publication time.

This row is code A: a award. An award is an acquisition but is not an open-market purchase. A purchase-following rule must not count it as code P.

Open the linked original receipts to verify the row, then inspect a second record before drawing a pattern. This public filing observation supplies source evidence, not a completed copy-trading return.

SEC 0001193125-26-445408 ↗SEC 0001193125-26-445394 ↗SEC 0001193125-26-355727 ↗

Recent Form 4 activity

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2026-11-032026-11-01Niemeyer Bruce LA1,276.71Not reported
2026-11-032026-11-01Dunn Micheal G.A1,276.71Not reported
2026-08-192026-08-14Peiffer Garry L.A1,232.17Not reported
2026-08-192026-08-14Walker Ray N JRA81.94Not reported
2026-08-192026-08-14SURMA JOHN PA1,563.43Not reported
2026-08-192026-08-14STICE J MICHAELA982.72Not reported
2026-08-192026-08-14SEMPLE FRANK MA1,072.72Not reported
2026-08-192026-08-14HELMS CHRISTOPHER AA1,336.96Not reported
2026-08-192026-08-14Breves Christine SA218.82Not reported

90-day public availability window, up to 50 records.

Recent institutional filing receipts

Inspect all 50 displayed rows: Recent institutional filing receipts

These are raw ticker-matched positions in recent 13F receipts, including amendments. They are not deduplicated current ownership totals. Open the manager profile to inspect its effective filing book.

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B. Riley Wealth Advisors, Inc.2025-03-312026-08-2921,555$1,153,610None
Advisors Asset Management, Inc.2021-12-312026-08-2892,207$2,728,405None
Advisors Asset Management, Inc.2022-12-312026-08-2884,333$2,769,496None
Advisors Asset Management, Inc.2020-06-302026-08-2853$916None
Advisors Asset Management, Inc.2020-06-302026-08-28111,808$1,932,042None
Advisors Asset Management, Inc.2022-06-302026-08-2888,350$2,575,000None
Advisors Asset Management, Inc.2021-09-302026-08-28102,894$2,929,000None
Corient Private Wealth LP2026-06-302026-08-28348,098$19,608,390None
VELA Investment Management, LLC2026-06-302026-08-2818,164$1,023,178None
VELA Investment Management, LLC2026-03-312026-08-2816,513$942,397None
VELA Investment Management, LLC2025-12-312026-08-2819,100$1,019,367Put
VELA Investment Management, LLC2025-12-312026-08-2835,346$1,886,416None
Wellington Grp LLC2026-06-302026-08-2715,589$878,128None
Advisors Asset Management, Inc.2024-03-312026-08-2760,485$2,513,757None
Advisors Asset Management, Inc.2025-03-312026-08-27111,882$5,987,925None
Advisors Asset Management, Inc.2022-09-302026-08-2782,246$2,468,000None
Advisors Asset Management, Inc.2020-12-312026-08-27109,452$2,370,000None
Advisors Asset Management, Inc.2022-03-312026-08-2787,582$2,905,971None
Advisors Asset Management, Inc.2023-06-302026-08-2778,226$2,654,990None
Advisors Asset Management, Inc.2023-09-302026-08-2766,993$2,382,941None
Advisors Asset Management, Inc.2023-03-312026-08-2776,526$2,636,321None
Advisors Asset Management, Inc.2021-03-312026-08-27106,751$2,736,028None
Advisors Asset Management, Inc.2021-06-302026-08-27107,151$3,173,000None
Advisors Asset Management, Inc.2020-09-302026-08-27111,060$1,748,084None
Advisors Asset Management, Inc.2025-09-302026-08-27149,367$7,460,882None
Advisors Asset Management, Inc.2023-12-312026-08-2768,191$2,503,974None
WILLIAM JOHN SEMPOLINSKI2026-03-312026-08-275,539$316,111None
WILLIAM JOHN SEMPOLINSKI2025-12-312026-08-274,839$258,257None
Advus Financial Partners, LLC2026-06-302026-08-266,191$348,739None
Advus Financial Partners, LLC2026-03-312026-08-266,000$342,420None
Advus Financial Partners, LLC2025-12-312026-08-266,000$320,220None
Advus Financial Partners, LLC2025-09-302026-08-266,000$299,700None
Advus Financial Partners, LLC2025-06-302026-08-266,000$309,060None
Advus Financial Partners, LLC2025-03-312026-08-266,000$321,120None
Advus Financial Partners, LLC2024-12-312026-08-266,000$287,160None
Advus Financial Partners, LLC2024-09-302026-08-266,000$266,760None
Advus Financial Partners, LLC2024-06-302026-08-265,481$233,436None
Advus Financial Partners, LLC2024-03-312026-08-265,481$227,790None
Advus Financial Partners, LLC2023-12-312026-08-265,481$201,262None
Advus Financial Partners, LLC2022-03-312026-08-266,376$211,556None
Advisors Asset Management, Inc.2019-12-312026-08-2653$1,349None
Advisors Asset Management, Inc.2019-12-312026-08-2695,738$2,437,489None
Advisors Asset Management, Inc.2025-06-302026-08-25128,590$6,623,671None
Advisors Asset Management, Inc.2024-09-302026-08-2260,517$2,690,586None
Advisors Asset Management, Inc.2024-06-302026-08-2262,676$2,669,371None
Advisors Asset Management, Inc.2024-12-312026-08-2287,484$4,186,984None
Advisors Asset Management, Inc.2025-12-312026-08-22157,932$8,428,831None
Advisors Asset Management, Inc.2020-03-312026-08-22115,090$1,337,346None
Rehmann Capital Advisory Group2026-06-302026-08-2115,173$854,695None
Archer Investment Corp2026-06-302026-08-20361$20,342None

90-day public filing window, up to 50 source positions.

B. Riley Wealth Advisors, Inc. ↗Advisors Asset Management, Inc. ↗Advisors Asset Management, Inc. ↗Advisors Asset Management, Inc. ↗Advisors Asset Management, Inc. ↗Advisors Asset Management, Inc. ↗Advisors Asset Management, Inc. ↗Corient Private Wealth LP ↗VELA Investment Management, LLC ↗VELA Investment Management, LLC ↗

Recent Congressional disclosures

No matching Congressional transactions were returned in this source preview.

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No records are available for this view.

Bounded public source preview, up to 25 disclosed events.

How to read the disclosure dates

The tables report different things: insider transactions, institutional positions and Congressional transaction ranges. Read each table with its source dates and units. They cannot be added into a combined ownership percentage.

  1. Company insiders

    SEC Form 4 purchases, sales and awards report transactions and their public filing availability.

  2. Institutional managers

    13F reports disclose delayed quarter-end positions. They are not a record of trades between quarters.

  3. Congressional filers

    Periodic transaction reports disclose transaction dates and amount brackets. Public filing dates determine what researchers could know.

Institutional source directory ↗Congressional source directory ↗

Read the transaction codes

Awards use transaction code A, purchases P and sales S. An acquisition from an award is not the same as an open-market purchase. Joint filers may share a transaction. Use original receipts and availability dates to interpret the events.