MPLX LP — Director's Dealing 2016

Sep 7, 2016

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: MPLX LP (MPLX)
CIK: 0001552000
Period of Report: 2016-09-01

Reporting Person: MPLX Holdings Inc. (Director, 10% Owner)

Holdings (Non-Derivative)

Security	Shares	Ownership
Class A Units	28554313	Indirect
Common Units (Limited Partner Interests)	79466136	Indirect

Footnotes

F1: Pursuant to a Master Reorganization Agreement effective September 1, 2016 by and among MPLX Holdings Inc. ("Holdings"), MarkWest Energy Partners, L.P., MWE GP LLC, MPLX LP ("MPLX"), MPLX GP LLC ("the "General Partner"), MPC Investment LLC ("MPC Investment"), MPLX Logistics Holdings LLC ("Logistics Holdings") and MarkWest Hydrocarbon, L.L.C. ("Hydrocarbon"), Holdings became a part of a reporting group which includes Marathon Petroleum Corporation ("MPC"), MPC Investment, the General Partner, Hydrocarbon and Logistics Holdings. MPC Investment, a direct wholly-owned subsidiary of MPC, owns all of the membership interests or stock in the General Partner, Logistics Holdings and Holdings. Holdings owned all of the membership interests in Hydrocarbon as of September 1, 2016. Accordingly, the General Partner, Logistics Holdings, Holdings and Hydrocarbon were all indirect wholly-owned subsidiaries of MPC as of the September 1, 2016.

F2: Hydrocarbon, a wholly-owned subsidiary of Holdings, owned all of the Issuer's Class A units as of September 1, 2016.

F3: As of September 1, 2016, the General Partner directly owned 7,630,225 general partner units, representing its 2% general partner interest in the Issuer and Logistics Holdings beneficially owned 79,466,136 common units representing limited partnership interests in the Issuer. MPC Investment owns all of the membership interests in Logistics Holdings and the General Partner, and MPC owns all of the membership interest in MPC Investment. Accordingly, MPC, MPC Investment and Holdings may be deemed to have indirectly beneficially owned the securities directly held by the General Partner, Logistics Holdings and Hydrocarbon but disclaim beneficial ownership except to the extent of their respective pecuniary interests therein.