633 managers (646 13F filers) reported a position in MPLX shares at 2026-03-31, 202,735,483 shares in all. 71 filers opened a position and 57 filers sold out during the quarter.
Managers
633
13F filers
646
New
71
Added
216
Reduced
173
Sold out
57
Shares held by filers
202,735,483
Shares held by filers adds up every 13F filer's report, so a share reported by a parent and by its subsidiary counts twice (H9). Managers counts each filer group once.
13D and 13G filers
No 13D or 13G on this security in the data. Structured 13D/G data starts 2024-12-18.
Insider trades
No Form 4 transaction on this security in the data.
13F holders, Q1 2026
Filers in the available 13F reports with a share position at 2026-03-31, filer groups collapsed to one row (method), largest first. Options and principal amounts are left out. A group row states no % of portfolio, since each member reports its own portfolio: the members' percents are listed under it. A value about 1,000 times or 1/1,000 of the price other filers imply is shown as filed but neither ranks the row nor enters a sum.