---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-177649"
form_type: "8-K"
ticker: "MPLX"
cik: "0001552000"
company_name: "MPLX LP"
filed_at: "2025-08-11T23:59:59+00:00"
generated_at: "2026-05-17T15:25:34.384893+00:00"
event_type: "debt"
sentiment: "neutral"
materiality_score: 0.5
calibrated_materiality_score: 0.5
confidence: "low"
source: SEC EDGAR
---

# MPLX LP executes underwriting agreement and supplemental indentures for new debt issuance

## Summary
- Underwriting agreement dated Aug 7, 2025 with J.P. Morgan, Goldman Sachs, BofA, Mizuho, TD, Wells Fargo as representatives.
- Four supplemental indentures (32nd through 35th) dated Aug 11, 2025 with Bank of New York Mellon as trustee.
- Debt issued under existing S-3 registration statement; terms (principal, rate, maturity) not disclosed in filing summary.
- Proceeds not specified; assumed general corporate purposes.

## SEC filing metadata
- accession: 0001193125-25-177649
- form_type: 8-K
- ticker: MPLX
- cik: 0001552000
- company_name: MPLX LP
- filed_at: 2025-08-11T23:59:59+00:00
- event_type: debt
- sentiment: neutral
- materiality_score: 0.5
- calibrated_materiality_score: 0.5
- confidence: low
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1552000/000119312525177649/0001193125-25-177649-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1552000/000119312525177649/d38882d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-177649
- JSON: https://secwatch.observer/filing/0001193125-25-177649.json
- Plain text: https://secwatch.observer/filing/0001193125-25-177649.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.