DOSSIER · 13F Holders · Q2 2026
MPLX LP
4 institutions still hold MPLX LP as of Q2 2026. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.
CUSIP 55336V900·4 13F holders·last filed Jun 30, 2026
AI Holders Summary · Q2 2026
4 institutions reported MPLX LP in Q2 2026. GROUP ONE TRADING LLC leads at 55.8% of the visible book.
Top holders
Sorted by position value. Source: SEC EDGAR 13F-HR filings.