MGNIMagnite, Inc.

$23.38

Who owns MGNI

294 institutions reported holding MGNI for 2026Q1, together 88% of the company, fewer than the 302 a quarter earlier.

294

Institutions reporting a position · as of 2026Q1 · down from 302 the quarter before

Shares held by institutions
131.0M

Shares held by institutions · 88% of the company · long US equity positions only, as reported on Form 13F

Reported value
$1.56B

Reported value · at 2026-03-31 prices, not today's

Top 5 holders
31%

Top 5 holders · of the whole company, between five filers

Details
Reporting quarter2026-03-31
2026Q1
Quarters on record
24
New positions
44
Positions exited
58
Added to
108
Reduced
74
Top 10 holdersof the company
45%
Institutional ownership by quarter, 2020Q2 to 2026Q1
QuarterFilersSharesReported value
2026Q1294131.0M$1.56B
2025Q4302136.7M$2.22B
2025Q3315137.7M$3.00B
2025Q2285146.9M$3.54B
2025Q1290132.6M$1.51B
2024Q4285123.2M$1.96B
2024Q3279119.6M$1.65B
2024Q2268104.3M$1.39B
2024Q1229102.1M$1.10B
2023Q4215102.6M$958M
2023Q3212103.5M$780M
2023Q2222101.7M$1.39B
2023Q122096.4M$892M
2022Q423093.3M$988M
2022Q3216103.3M$679M
2022Q222888.0M$781M
Largest reported holders, 2026Q1
HolderShares% of companyValue
VANGUARD GROUP INC15.1M10%$180M
BlackRock Inc.11.7M7.9%$138M
WELLINGTON MANAGEMENT GROUP LLP9.2M6.2%$109M
Capital Research Global Investors5.0M3.4%$60M
Robeco Investment Management, Inc.4.7M3.2%$56M
AMERICAN CENTURY COMPANIES INC4.6M3.1%$55M
FMR LLC4.5M3.0%$54M
DIMENSIONAL FUND ADVISORS LP4.0M2.7%$47M
Nuveen Asset Management, LLC3.6M2.4%$43M
GEODE CAPITAL MANAGEMENT LLC3.6M2.4%$42M

SEC Form 13F data sets (DERA bulk files). 13F is quarterly, filed up to 45 days late, and covers long US equity positions only, no shorts, no derivatives, nothing held below the reporting threshold.

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