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MGNIInformation TechnologyCommon Stock

Magnite, Inc

Held by 9 tracked managers as of Q2 2026 · CUSIP ⓘCUSIP: A 9-character ID for one specific security - one share class of one company, or one bond. Tickers can change and can mean different things in different countries; a CUSIP always identifies exactly the same security, which is why filings use it. Guide 55955D100 · Sector ⓘGICS sectors: The 11-sector system most investors know (Global Industry Classification Standard): Technology, Health Care, Financials and so on. This site assigns each company a GICS-style sector from its SIC code, with a few hand corrections, so sector pages match the names investors expect. Guide

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In plain English: 9 of the investors we track own this stock. In the latest quarter, 5 of them bought more of it and 3 sold some or all of theirs (1 bought it for the first time). That tells you what they did last quarter — not what the stock will do next.

Educational and informational only, not personalized investment advice. Based on public filings that may be delayed or contain errors; verify with the original filings. Disclaimer

Managers holding
9
+1 vs last quarter (like-for-like)
Total value held
$166.98M
Across tracked managers
Average weight ⓘOn average, how big this stock is in the portfolios that own it (its share of each manager's reported portfolio value).
0.1%
Of each manager's book
QoQ value ⓘLike-for-like: only managers that filed both quarters are compared, so a manager filing late (or confidentially) does not look like buying or selling. Includes price changes.
+$54.08M
+47.9% vs last quarter
Net shares bought
-741.3K
Est. net flow -$14.03M
Quarter activity
5 bought · 3 sold
1 new · 0 sold out

Tracked capital in this stock

Total value held (area) and number of managers (line). Dips can mean a large holder filed that quarter confidentially (e.g. Norges Bank in Q1/Q3).

Chart: Tracked capital in this stock

Aggregate buying and selling

Net share change reported each quarter

Chart: Aggregate buying and selling

Who owns MGNI?

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Who owns MGNI? — Q2 2026

Holders ranked by position size, with each one's quarter-over-quarter change.

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

# Manager Fund Shares Value ↓ % of their portfolio QoQ Δ shares Δ shares % Est. Δ value ⓘChange in shares × this quarter's price
1 Boston Partners Boston Partners Global Investors 5.01M $95.85M 0.1% Added +294.0K +6.2% +$5.62M
2 Chuck Royce Royce & Associates 1.47M $27.97M 0.2% Added +107.9K +7.9% +$2.05M
3 Israel Englander Millennium Management 764.82K $14.52M 0.0% Reduced -469.6K -38.0% -$8.91M
4 Matthew McLennan First Eagle Investment Management 670.79K $12.73M 0.0% Added +220.5K +49.0% +$4.19M
5 Ken Griffin Citadel Advisors 472.87K $8.97M 0.0% Reduced -580.0K -55.1% -$11.01M
6 Richard Mashaal Senvest Management 224.10K $4.25M 0.1% Held 0 0.0% $0
7 Mario Gabelli GAMCO Investors 63.10K $1.20M 0.0% Added +2.4K +4.0% +$46.46K
8 Two Sigma Two Sigma Investments 42.66K $809.67K 0.0% Reduced -352.2K -89.2% -$6.68M
9 David Shaw D.E. Shaw & Co. 35.72K $677.95K 0.0% New +35.7K — +$677.95K

Sold out completely this quarter

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

No tracked manager sold out of this stock this quarter.

Politician trades

Politician trades in MGNI

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

No politician trades match these filters.