MAGNITE INC (MGNI) Institutional Ownership Changes & 13F Activity
MAGNITE INC (MGNI). Institutional ownership data tracks hedge funds, asset managers, and other institutional investors based on recent SEC Form 13F filings (Q2 2026). This page analyzes institutional buying and selling activity, new holdings, and sold-out positions in the latest reporting period. Notable filers include Wellington Management Group Llp, Canada Pension Plan Investment Board, 325 Capital Llc, Park West Asset Management Llc, and Qube Research & Technologies Ltd.
| Institution | Type | Change in shares | Change Position % | Shares | Reported stock balance | Portfolio quarter | Filing date |
|---|---|---|---|---|---|---|---|
| Manufacturers Life Insurance Company, The | Buy | +6,457 | +10.0% | 71,015 | $1.35M | Q2 2026 | Sep 09, 2026 |
| Parkside Financial Bank & Trust | Sell | -275 | -2.5% | 10,538 | $200.01K | Q2 2026 | Sep 04, 2026 |
| Citadel Advisors Llc | Sell | -580,043 | -55.1% | 472,865 | $8.97M | Q2 2026 | Sep 02, 2026 |
| Cornerstone Financial Management Llc | Buy | +34 | — | 34 | $645.00 | Q2 2026 | Aug 28, 2026 |
| Corient Private Wealth Llc | Buy | +25,326 | — | 25,326 | $480.69K | Q2 2026 | Aug 27, 2026 |
| First Eagle U.S. Value | Buy | +220,500 | +49.0% | 670,788 | $12.73M | Q2 2026 | Aug 24, 2026 |
| California State Teachers Retirement System | Sell | -4,481 | -2.5% | 172,047 | $3.27M | Q2 2026 | Aug 24, 2026 |
| Mercer Global Advisors Inc | Buy | +9,916 | +53.7% | 28,374 | $538.54K | Q2 2026 | Aug 19, 2026 |
| Wellington Management Group Llp | Sell | -3,146,585 | -34.2% | 6,044,492 | $114.72M | Q2 2026 | Aug 14, 2026 |
| Canada Pension Plan Investment Board | Buy | +2,949,041 | +6403.7% | 2,995,093 | $56.85M | Q2 2026 | Aug 14, 2026 |
| 325 Capital Llc | Buy | +1,407,307 | +70.2% | 3,412,694 | $64.77M | Q2 2026 | Aug 14, 2026 |
| Park West Asset Management Llc | Buy | +1,401,620 | +234.2% | 2,000,000 | $37.96M | Q2 2026 | Aug 14, 2026 |
| Qube Research & Technologies Ltd | Buy | +1,294,932 | +195.9% | 1,955,989 | $37.12M | Q2 2026 | Aug 14, 2026 |
| Schonfeld Strategic Advisors Llc | Sell | -1,042,846 | -65.0% | 562,195 | $10.67M | Q2 2026 | Aug 14, 2026 |
| Balyasny Asset Management L.P. | Sell | -833,889 | -55.6% | 666,554 | $12.65M | Q2 2026 | Aug 14, 2026 |
| Ophir Asset Management Pty Ltd | Sell | -667,955 | -31.5% | 1,450,061 | $27.52M | Q2 2026 | Aug 14, 2026 |
| Ameriprise Financial Inc | Buy | +619,573 | — | 619,573 | $11.76M | Q2 2026 | Aug 14, 2026 |
| Man Group Plc | Sell | -610,903 | -92.0% | 53,054 | $1.01M | Q2 2026 | Aug 14, 2026 |
| Jane Street Group, Llc | Buy | +531,031 | +31.8% | 2,199,191 | $41.74M | Q2 2026 | Aug 14, 2026 |
| Granahan Investment Management, Llc | Buy | +529,798 | +20.7% | 3,083,211 | $58.52M | Q2 2026 | Aug 14, 2026 |
| Millennium Management Llc | Sell | -469,638 | -38.0% | 764,819 | $14.52M | Q2 2026 | Aug 14, 2026 |
| Two Sigma Investments, Lp | Sell | -352,197 | -89.2% | 42,659 | $809.67K | Q2 2026 | Aug 14, 2026 |
| Trexquant Investment Lp | Buy | +333,429 | — | 333,429 | $6.33M | Q2 2026 | Aug 14, 2026 |
| Alyeska Investment Group, L.P. | Buy | +326,839 | — | 326,839 | $6.20M | Q2 2026 | Aug 14, 2026 |
| Qvt Financial Lp | Buy | +293,527 | +64.7% | 747,437 | $14.19M | Q2 2026 | Aug 14, 2026 |
| Caption Management, Llc | Sell | -259,463 | -64.1% | 145,590 | $2.76M | Q2 2026 | Aug 14, 2026 |
| Invesco Ltd. | Buy | +222,213 | — | 222,213 | $4.22M | Q2 2026 | Aug 14, 2026 |
| Nine Ten Capital Management Llc | Sell | -220,000 | -6.3% | 3,261,283 | $61.90M | Q2 2026 | Aug 14, 2026 |
| Pillsbury Lake Capital Llc | Buy | +217,753 | — | 217,753 | $4.13M | Q2 2026 | Aug 14, 2026 |
| Occam Crest Management Lp | Buy | +195,000 | — | 195,000 | $3.85M | Q2 2026 | Aug 14, 2026 |
Frequently asked questions about MGNI activity
Which institutional owners are buying MGNI?
Institutional owners buying MGNI include investors who have either initiated new positions or increased their existing holdings based on recent SEC 13F filings. The activity table above highlights which funds added shares in the latest reporting periods and how their positions changed over time.
What does "buy" mean in MGNI activity?
"Buy" means an investor increased their reported position in MGNI compared to the prior reporting period. This reflects growing exposure to MAGNITE INC (MGNI) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).
Is institutional interest in MGNI increasing?
Institutional interest in MGNI can be assessed by comparing the number of tracked funds adding or increasing positions versus those trimming or exiting across the periods shown. A higher number of additions typically signals increasing participation among large filers, but it should be read alongside position sizes and the full table.
Related MGNI Institutional Insights
- MGNI Overview
- MGNI 13F Institutional Holders
- MGNI Top Institutional Shareholders
- Communication Services Sector Institutional Ownership
- Communication Services Sector Portfolio Overlap
- Institutional Portfolio Overlap & Shared Holdings
- Most Bought Communication Services Stocks By Institutional Investors
- Most Sold Communication Services Stocks By Institutional Investors
- MGNI Insider Trading & SEC Form 4 Activity
- MGNI Articles
- Top Institutional Investor Stock Rankings