How many institutional investors hold MGNI?

4 tracked institutional investors disclosed a position in MGNI (MAGNITE INC) in their most recent 13F filing.

Who is the largest institutional holder of MGNI?

Ken Griffin, Citadel Advisors, holds the largest disclosed position in MGNI, valued at $28M.

Where does this MGNI 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.

MGNI — MAGNITE INC

Name: MAGNITE INC (MGNI) — 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 MAGNITE INC (MGNI)

MAGNITE INC (MGNI) appears in the most recent 13F filings of 4 tracked institutional investors. The largest disclosed position is held by Ken Griffin (Citadel Advisors), valued at $28M. Across recent filings, tracked investors recorded 1 new positions, 0 increased, 1 reduced, and 1 exited. All data sourced from SEC 13F filings.

Smart Money Consensus™

Based on recent institutional activity in MGNI

/100

Institutional Distribution

Added / Increased1

Reduced1

Exited1

BearishBullish

Crowded Trade Score™

How many top investors track MGNI

/100

Emerging Interest

4investors

A small number of top investors own this.

UndiscoveredCrowded

151015+

MGNI Ownership Composition

How MAGNITE INC is held across tracked investor types, based on reported 13F positions.

Dominant Type

Other

99% of tracked value

Institutions

tracked investors

Total Reported

$43.5M

combined 13F value

Other99.1%
Hedge Funds0.9%

Other(3)

99.1%

Hedge Funds(1)

0.9%

Tracked investors reporting MGNI

Investor	Firm	Shares	Market value	% of portfolio	As of
Ken Griffin	Citadel Advisors	2.2M	$26.1M	0.00%	Mar 31, 2026
Izzy Englander	Millennium Management	1.2M	$14.7M	0.01%	Mar 31, 2026
Ray Dalio	Bridgewater Associates	145.2K	$2.4M	0.03%	Dec 31, 2025
Steve Cohen	Point72 Asset Management	23.5K	$381.4K	0.00%	Dec 31, 2025

Ken GriffinMar 31, 2026
Citadel Advisors
Shares
2.2M
Value
$26.1M
% Portfolio
0.00%
Izzy EnglanderMar 31, 2026
Millennium Management
Shares
1.2M
Value
$14.7M
% Portfolio
0.01%
Ray DalioDec 31, 2025
Bridgewater Associates
Shares
145.2K
Value
$2.4M
% Portfolio
0.03%
Steve CohenDec 31, 2025
Point72 Asset Management
Shares
23.5K
Value
$381.4K
% Portfolio
0.00%

Recent activity

Investor	Action	Δ %	Current value	Filing date
Ray Dalio	Sold	-100.00%	$0	May 15, 2026
Ray Dalio	Reduced	-0.33%	$2.4M	Feb 13, 2026
Ray Dalio	New	—	$3.2M	Nov 13, 2025

Ray Dalio
Sold
$0(-100.00%)May 15, 2026
Ray Dalio
Reduced
$2.4M(-0.33%)Feb 13, 2026
Ray Dalio
New
$3.2MNov 13, 2025

Frequently asked questions

How many institutional investors hold MGNI?: 4 tracked institutional investors disclosed a position in MGNI (MAGNITE INC) in their most recent 13F filing.
Who is the largest institutional holder of MGNI?: Ken Griffin, Citadel Advisors, holds the largest disclosed position in MGNI, valued at $28M.
Did institutional ownership of MGNI increase or decrease?: Across recent 13F filings, tracked investors recorded 1 new positions, 0 increased, 1 reduced, and 1 fully exited MGNI.
Where does this MGNI 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.