Here are the Form 4 insider transactions from MPLX LP (MPLX) in our archive over the last 12 months, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A Form 4 covers the transactions officers, directors and large holders report, so if you follow MPLX and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full MPLX filings page.
MPLX LP (MPLX) director Frank M. Semple reported acquiring 1,132.302 common units on 11/14/2025, according to a Form 4 insider filing. The units were acquired at a reported price of $0, indicating an award or similar non-cash grant rather than an open-market purchase. Following this transaction, Semple directly holds 57,100.516 MPLX common units. He also reports additional indirect holdings of 333,337 units through the Frank M Semple Revocable Trust, 111,180 units through the Robin Y Semple 2012 Dynasty Trust, and 48,777 units through EK Holdings LLC. Semple serves as a director of MPLX GP LLC, the general partner that manages MPLX LP.
MPLX LP director Garry L. Peiffer reported acquiring additional common units of the master limited partnership. On 11/14/2025, he acquired 1,247.144 MPLX common units (limited partner interests) at a reported price of $0, suggesting these were likely granted rather than purchased in the open market. Following this transaction, he beneficially owns 62,891.819 common units in a direct capacity and an additional 68,497 common units indirectly through the Garry L. Peiffer Revocable Trust. The filing confirms this is an individual Form 4 for one reporting person in his capacity as a director of MPLX GP LLC, the general partner that manages MPLX LP.
MPLX LP reported an insider transaction on Form 4 involving director Christopher A. Helms. On 11/14/2025, Helms acquired 1,357.679 MPLX common units (limited partner interests) at a reported price of $0 per unit, increasing his direct holdings. Following this transaction, he beneficially owned 79,465.942 common units directly. MPLX is managed by the directors and executive officers of MPLX GP LLC, where Helms serves as a director.
MPLX LP disclosed that one of its directors acquired additional equity in the company. On 11/14/2025, the reporting person received 230.413 MPLX common units (limited partner interests) in an acquisition transaction reported at a price of $0 per unit, which suggests a grant rather than an open-market purchase. After this transaction, the director beneficially owns 11,619.354 MPLX common units, held directly. The director serves on the board of MPLX GP LLC, which is the general partner that manages MPLX LP through its directors and executive officers.