Here are the 424B prospectus supplements from Mplx LP PFD CL A (MPLXP) 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 424B covers the supplement that carries the terms of a priced offering, so if you follow MPLXP 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 MPLXP filings page.
MPLX LP is issuing $2,250,000,000 of senior unsecured notes: $1.25 billion 4.700% notes due 2029, $500 million 5.000% notes due 2032, and $500 million 5.500% notes due 2036. Interest is paid semi-annually on May 1 and November 1, starting May 1, 2027.
The notes are senior unsecured obligations of MPLX LP, effectively junior to secured debt and structurally subordinated to all liabilities of its subsidiaries. MPLX expects net proceeds of approximately $2,210 million, to be used to repay $1,250 million 4.125% senior notes due March 2027, with the remainder for general partnership purposes including capital expenditures and working capital.
As of June 30, 2026, total consolidated debt was $26,005 million, which would be about $27,005 million on an as-adjusted basis after this offering and the planned use of proceeds. MPLX maintains a $2.5 billion unsecured revolving credit facility with a maximum Consolidated Total Debt to Consolidated EBITDA ratio of 5.0 to 1.0 under its covenant.
MPLX LP plans to issue three new series of unsecured, unsubordinated senior notes under its existing indenture. Each series will pay fixed interest semi-annually beginning in 2027, may be redeemed at MPLX’s option (including a Treasury-based make‑whole call before specified Par Call Dates), and will rank equally with MPLX’s other senior unsecured debt but be effectively junior to any secured debt and structurally subordinated to obligations of its subsidiaries.
MPLX reports consolidated debt of $26,005 million as of June 30, 2026 and intends to use the net proceeds to repay or redeem its $1,250 million 4.125% senior notes due March 2027, with any remaining proceeds for general partnership purposes such as capital expenditures and working capital. MPLX is a large-cap master limited partnership sponsored and controlled by Marathon Petroleum Corporation, which owned about 64% of MPLX’s outstanding common units as of June 30, 2026.
The new notes are not protected by a change‑of‑control put, are not guaranteed by subsidiaries, and have no sinking fund. The base indenture contains limited covenants on liens and sale‑leaseback transactions tied to assets designated as principal properties and includes standard events of default, merger restrictions, and defeasance provisions. The notes will be issued only in book‑entry form through DTC, with no application for listing on any securities exchange.