MGNI Institutional Ownership & Shareholders
MAGNITE INC (MGNI) is currently held by 317 institutional investors tracked by InsiderSet, with a combined reported market value of approximately $2.69B based on the latest available SEC Form 13F filings for the quarter ended June 30, 2026.
Blackrock, Inc. is currently the largest disclosed institutional shareholder of MGNI tracked by InsiderSet, reporting ownership valued at approximately $241.30M in its June 30, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $275.11M, representing an estimated gain of +14.01% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 45% of the total disclosed MGNI value among the investors covered in this analysis. Major shareholders include Blackrock, Inc., Vanguard Portfolio Management Llc, Fmr Llc, and several other long-term asset managers with concentrated positions in MAGNITE INC (MGNI).
This page ranks the largest institutional MGNI shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
Institutional Holders
317
Total Reported Value
$2.69B
Largest Holder
Blackrock, Inc.
Largest Position
$241.30M
Insider Transactions (90d)
40
Latest Filing Quarter
Q2 2026
New Institutional Positions
56
Funds Exiting Positions
0
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Blackrock, Inc. | 0.00% | 12,713,156 | $241,295,708 | $275,112,696 | +$33,816,988 | +14.01% | |
| Vanguard Portfolio Management Llc | 0.01% | 8,197,286 | $155,584,488 | $177,389,269 | +$21,804,781 | +14.01% | |
| Fmr Llc | 0.01% | 7,759,426 | $147,273,902 | $167,913,979 | +$20,640,077 | +14.01% | |
| Vanguard Capital Management Llc | 0.00% | 6,225,195 | $118,154,201 | $134,713,220 | +$16,559,019 | +14.01% | |
| Wellington Management Group Llp | 0.02% | 6,044,492 | $114,724,458 | $130,802,807 | +$16,078,349 | +14.01% | |
| Dimensional Fund Advisors Lp | 0.02% | 5,260,132 | $99,838,708 | $113,829,256 | +$13,990,548 | +14.01% | |
| Boston Partners | 0.09% | 5,013,835 | $95,854,485 | $108,499,389 | +$12,644,904 | +13.19% | |
| American Century Companies Inc | 0.04% | 4,622,736 | $87,739,553 | $100,036,007 | +$12,296,454 | +14.01% | |
| Capital Research Global Investors | 0.01% | 3,869,159 | $73,436,638 | $83,728,601 | +$10,291,963 | +14.01% | |
| Nuveen, Llc | 0.02% | 3,794,811 | $72,025,513 | $82,119,710 | +$10,094,197 | +14.01% | |
| Geode Capital Management, Llc | 0.00% | 3,789,959 | $71,946,545 | $82,014,713 | +$10,068,168 | +13.99% | |
| Edenbrook Capital, Llc | 23.59% | 3,555,615 | $67,485,573 | $76,943,509 | +$9,457,936 | +14.01% | |
| State Street Corp | 0.00% | 3,528,075 | $66,962,864 | $76,347,543 | +$9,384,679 | +14.01% | |
| 325 Capital Llc | 15.44% | 3,412,694 | $64,772,932 | $73,850,698 | +$9,077,766 | +14.01% | |
| Nine Ten Capital Management Llc | 19.26% | 3,261,283 | $61,899,000 | $70,574,164 | +$8,675,164 | +14.02% | |
| Granahan Investment Management, Llc | 2.09% | 3,083,211 | $58,519,345 | $66,720,686 | +$8,201,341 | +14.01% | |
| Canada Pension Plan Investment Board | 0.03% | 2,995,093 | $56,846,865 | $64,813,813 | +$7,966,948 | +14.01% | |
| Jane Street Group, Llc | 0.03% | 2,199,191 | $41,740,645 | $47,590,493 | +$5,849,848 | +14.01% | |
| Park West Asset Management Llc | 2.59% | 2,000,000 | $37,960,000 | $43,280,000 | +$5,320,000 | +14.01% | |
| Morgan Stanley | 0.00% | 1,991,732 | $37,803,076 | $43,101,080 | +$5,298,004 | +14.01% | |
| Qube Research & Technologies Ltd | 0.04% | 1,955,989 | $37,124,671 | $42,327,602 | +$5,202,931 | +14.01% | |
| Blue Grotto Capital, Llc | 2.70% | 1,706,741 | $32,393,945 | $36,933,875 | +$4,539,930 | +14.01% | |
| Kennedy Capital Management Llc | 0.56% | 1,666,799 | $31,635,845 | $36,069,530 | +$4,433,685 | +14.01% | |
| Northern Trust Corp | 0.00% | 1,553,412 | $29,483,760 | $33,615,836 | +$4,132,076 | +14.01% | |
| Maestria Partners Llc | 9.82% | 1,158,430 | $29,261,942 | $25,068,425 | -$4,193,517 | -14.33% | |
| Royce & Associates Lp | 0.23% | 1,473,397 | $27,965,075 | $31,884,311 | +$3,919,236 | +14.01% | |
| Goldman Sachs Group Inc | 0.00% | 1,466,640 | $27,836,827 | $31,738,090 | +$3,901,263 | +14.01% | |
| Ophir Asset Management Pty Ltd | 2.26% | 1,450,061 | $27,522,158 | $31,379,320 | +$3,857,162 | +14.01% | |
| Victory Capital Management Inc | 0.01% | 1,235,384 | $23,447,589 | $26,733,710 | +$3,286,121 | +14.01% | |
| Charles Schwab Investment Management Inc | 0.00% | 1,203,189 | $22,836,527 | $26,037,010 | +$3,200,483 | +14.01% | |
| Bank Of America Corp | 0.00% | 1,181,832 | $22,431,171 | $25,574,844 | +$3,143,673 | +14.01% | |
| Grizzlyrock Capital, Llc | 15.46% | 1,164,628 | $22,104,639 | $25,202,550 | +$3,097,911 | +14.01% | |
| Bank Of New York Mellon Corp | 0.00% | 1,162,198 | $22,058,518 | $25,149,965 | +$3,091,447 | +14.01% | |
| Meros Investment Management, Lp | 5.97% | 991,335 | $18,815,538 | $21,452,489 | +$2,636,951 | +14.01% | |
| Vanguard Fiduciary Trust Co | 0.00% | 989,092 | $18,772,966 | $21,403,951 | +$2,630,985 | +14.01% | |
| Millennium Management Llc | 0.01% | 764,819 | $14,516,265 | $16,550,683 | +$2,034,418 | +14.01% | |
| Qvt Financial Lp | 0.91% | 747,437 | $14,186,354 | $16,174,537 | +$1,988,183 | +14.01% | |
| Ubs Group Ag | 0.00% | 746,350 | $14,165,723 | $16,151,014 | +$1,985,291 | +14.01% | |
| Oberweis Asset Management Inc/ | 0.29% | 735,000 | $13,950,300 | $15,905,400 | +$1,955,100 | +14.01% | |
| Silvercrest Asset Management Group Llc | 0.09% | 707,749 | $13,433,076 | $15,315,688 | +$1,882,612 | +14.01% | |
| Picton Mahoney Asset Management | 0.12% | 691,471 | $13,124,123 | $14,963,432 | +$1,839,309 | +14.01% | |
| Kopion Asset Management, Llc | 8.38% | 519,164 | $13,114,083 | $11,234,709 | -$1,879,374 | -14.33% | |
| First Eagle U.S. Value | Jean-Marie Eveillard | 0.02% | 670,788 | $12,731,556 | $14,515,852 | +$1,784,296 | +14.01% |
| Balyasny Asset Management L.P. | 0.02% | 666,554 | $12,651,195 | $14,424,229 | +$1,773,034 | +14.01% | |
| Ameriprise Financial Inc | 0.00% | 619,573 | $11,759,490 | $13,407,560 | +$1,648,070 | +14.01% | |
| S Squared Technology, Llc | 3.34% | 567,862 | $10,778,021 | $12,288,534 | +$1,510,513 | +14.01% | |
| Schonfeld Strategic Advisors Llc | 0.06% | 562,195 | $10,670,460 | $12,165,900 | +$1,495,440 | +14.01% | |
| Nomura Asset Management Co Ltd | 0.02% | 553,900 | $10,513,022 | $11,986,396 | +$1,473,374 | +14.01% | |
| Bank Of Montreal | 0.00% | 533,757 | $10,130,708 | $11,550,501 | +$1,419,793 | +14.01% | |
| King Luther Capital Management Corp | 0.04% | 503,581 | $9,557,967 | $10,897,493 | +$1,339,526 | +14.01% |
Frequently asked questions about MGNI
Who are the largest institutional holders of MGNI?
The largest institutional holders of MGNI reported in the latest SEC Form 13F filings include Blackrock, Inc., Vanguard Portfolio Management Llc, Fmr Llc, Vanguard Capital Management Llc, and Wellington Management Group Llp. InsiderSet ranks institutional holders by their latest reported MGNI position.
What is MGNI institutional ownership?
This page tracks MGNI positions reported by institutional investment managers through SEC Form 13F. MAGNITE INC (MGNI) institutional ownership on InsiderSet reflects disclosed 13F holdings among the managers we analyze, not every shareholder of the stock.
How many institutions own MGNI?
InsiderSet currently tracks 317 institutional managers reporting MGNI holdings in the latest available 13F data. This count reflects institutions included in the SEC Form 13F filings analyzed by InsiderSet and should not be interpreted as the total number of MGNI shareholders.
How much MGNI stock do institutions own?
Institutional investment managers disclosed approximately $2.69B in MGNI holdings for Q2 2026. This figure is reported 13F value as of the filing period, not necessarily today's market value.
When was MGNI institutional ownership last updated?
The latest MGNI institutional ownership data on InsiderSet is based on SEC Form 13F filings for the quarter ended June 30, 2026. Form 13F filings are generally reported after the quarter ends, so the holdings shown represent the latest publicly disclosed positions rather than real-time institutional holdings.
Are institutional MGNI holdings real-time?
No. Form 13F data is not real-time. It represents positions reported by institutional investment managers as of the end of the reporting quarter. An institution may have changed its MGNI position after the reporting date.
Are institutions buying or selling MGNI?
Institutional buying and selling can be analyzed by comparing MGNI positions across consecutive 13F reporting periods. InsiderSet's MGNI Ownership Changes page shows institutions that increased, reduced, initiated, or exited positions based on reported 13F holdings. View MGNI ownership changes.
How has MGNI institutional ownership changed over time?
InsiderSet tracks MGNI institutional holdings across multiple 13F reporting periods, allowing investors to compare institutional holder counts, reported value, and reported shares over time.