How many institutional investors hold MPLX?

2 tracked institutional investors disclosed a position in MPLX (MPLX LP) in their most recent 13F filing.

Who is the largest institutional holder of MPLX?

Ken Griffin, Citadel Advisors, holds the largest disclosed position in MPLX, valued at $55M.

Where does this MPLX ownership data come from?

SEC Form 13F-HR filings, accessed via EDGAR. 13F filings are disclosed quarterly with a 45-day reporting delay and cover U.S.-listed long equity positions only. This is not investment advice.

MPLX — MPLX LP

Name: MPLX LP (MPLX) — Institutional Ownership
Creator: InvestorLens
License: https://www.sec.gov/about/website-policies

Public company

For educational research only.InvestorLens analyzes public regulatory filings (SEC EDGAR, STOCK Act PTRs) that may be delayed by 45 days or more. Information shown is historical and is not financial, legal, or tax advice, nor a recommendation or solicitation to buy or sell any security. Always do your own research.

InvestorLens aggregates public filing data to show which tracked investors reported holdings in this stock. Dollar values represent reported position values, not market capitalization, and may be delayed up to 45 days. Not a recommendation.

Sourced from SEC EDGAR public filings

About MPLX LP (MPLX)

MPLX LP (MPLX) appears in the most recent 13F filings of 2 tracked institutional investors. The largest disclosed position is held by Ken Griffin (Citadel Advisors), valued at $55M. Across recent filings, tracked investors recorded 1 new positions, 1 increased, 1 reduced, and 0 exited. All data sourced from SEC 13F filings.

Smart Money Consensus™

Based on recent institutional activity in MPLX

/100

Institutional Accumulation

Added / Increased2

Reduced1

Exited0

BearishBullish

Crowded Trade Score™

How many top investors track MPLX

/100

Undiscovered

2investors

Only 2 tracked investors report this position.

UndiscoveredCrowded

151015+

MPLX Ownership Composition

How MPLX LP is held across tracked investor types, based on reported 13F positions.

Dominant Type

Other

100% of tracked value

Institutions

tracked investors

Total Reported

$56.5M

combined 13F value

Other100.0%

Other(2)

100.0%

Tracked investors reporting MPLX

Investor	Firm	Shares	Market value	% of portfolio	As of
Ken Griffin	Citadel Advisors	488K	$27.9M	0.00%	Mar 31, 2026
David Tepper	Appaloosa Management	502.5K	$28.7M	0.48%	Mar 31, 2026

Ken GriffinMar 31, 2026
Citadel Advisors
Shares
488K
Value
$27.9M
% Portfolio
0.00%
David TepperMar 31, 2026
Appaloosa Management
Shares
502.5K
Value
$28.7M
% Portfolio
0.48%

Recent activity

Investor	Action	Δ %	Current value	Filing date
David Tepper	Reduced	-19.93%	$28.7M	May 15, 2026
David Tepper	Increased	17.29%	$33.5M	Feb 17, 2026
David Tepper	New	—	$26.7M	Nov 13, 2025

David Tepper
Reduced
$28.7M(-19.93%)May 15, 2026
David Tepper
Increased
$33.5M(17.29%)Feb 17, 2026
David Tepper
New
$26.7MNov 13, 2025

Frequently asked questions

How many institutional investors hold MPLX?: 2 tracked institutional investors disclosed a position in MPLX (MPLX LP) in their most recent 13F filing.
Who is the largest institutional holder of MPLX?: Ken Griffin, Citadel Advisors, holds the largest disclosed position in MPLX, valued at $55M.
Did institutional ownership of MPLX increase or decrease?: Across recent 13F filings, tracked investors recorded 1 new positions, 1 increased, 1 reduced, and 0 fully exited MPLX.
Where does this MPLX ownership data come from?: SEC Form 13F-HR filings, accessed via EDGAR. 13F filings are disclosed quarterly with a 45-day reporting delay and cover U.S.-listed long equity positions only. This is not investment advice.