Magnite, Inc. (MGNI) Insider Trading
Over the last 3 months, MGNI insiders made 0 open-market buys and 31 sales, a net sale of -$21.4M (SEC Form 4). Over the last 6 months, 228 institutions increased and 179 reduced their position (13F).
Insider Activity
Sentiment
0/100
Buys (3m)
0
Sells (3m)
31
Net (3m)
-$21.4M
Insider trades by month Buys Sells
Dec
Feb
May
Jun
Jul
Aug
Context3-month price +52.2%Institutions accumulating (13F)
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| Aug 28, 2026 | Harden Sarah Patriciadirector | Sell | 18,436 | $24.00 |
| Aug 28, 2026 | Harden Sarah Patriciadirector | Sell | 30,550 | $23.31 |
| Aug 18, 2026 | Saltz Aaronofficer: CHIEF LEGAL OFFICER | Tax | 5,627 | $24.73 |
| Aug 18, 2026 | Caine Pauldirector | Sell | 7,500 | $25.00 |
| Aug 18, 2026 | Evans Katie Seitzofficer: See Remarks | Tax | 11,204 | $24.73 |
| Aug 18, 2026 | Buckley Sean Patrickofficer: See Remarks | Sell | 2,759 | $25.00 |
| Aug 18, 2026 | Buckley Sean Patrickofficer: See Remarks | Tax | 11,715 | $24.73 |
| Aug 18, 2026 | Gephart Brianofficer: CHIEF ACCOUNTING OFFICER | Tax | 3,789 | $24.73 |
| Aug 18, 2026 | Buonasera Davidofficer: CHIEF TECHNOLOGY OFFICER | Tax | 8,102 | $24.73 |
| Aug 18, 2026 | Day Davidofficer: CHIEF FINANCIAL OFFICER | Tax | 14,170 | $24.73 |
| Aug 18, 2026 | BARRETT MICHAEL G.director, officer: CEO | Tax | 10,404 | $24.73 |
| Aug 18, 2026 | Buckley Sean Patrickofficer: See Remarks | Sell | 8,271 | $24.31 |
| Aug 12, 2026 | Lam Racheldirector | Sell | 10,000 | $24.16 |
| Aug 12, 2026 | Gephart Brianofficer: CHIEF ACCOUNTING OFFICER | Sell | 12,479 | $24.68 |
| Aug 12, 2026 | Caine Pauldirector | Sell | 5,000 | $24.35 |
| Aug 7, 2026 | BARRETT MICHAEL G.director, officer: CEO | Option | 293,968 | $5.80 |
| Aug 7, 2026 | Buckley Sean Patrickofficer: See Remarks | Option | 28,703 | $13.90 |
| Aug 7, 2026 | Knopper Douglas Sdirector | Sell | 37,337 | $22.72 |
| Aug 7, 2026 | Buckley Sean Patrickofficer: See Remarks | Sell | 47,942 | $25.09 |
| Aug 7, 2026 | Buonasera Davidofficer: CHIEF TECHNOLOGY OFFICER | Sell | 871 | $25.00 |
| Aug 7, 2026 | Buckley Sean Patrickofficer: See Remarks | Sell | 19,237 | $23.00 |
| Aug 7, 2026 | BARRETT MICHAEL G.director, officer: CEO | Sell | 293,968 | $22.72 |
| Aug 7, 2026 | Buonasera Davidofficer: CHIEF TECHNOLOGY OFFICER | Sell | 4,176 | $22.81 |
| Aug 7, 2026 | Evans Katie Seitzofficer: See Remarks | Option | 20,000 | $5.16 |
| Aug 7, 2026 | Evans Katie Seitzofficer: See Remarks | Sell | 20,000 | $24.00 |
| Aug 7, 2026 | Buonasera Davidofficer: CHIEF TECHNOLOGY OFFICER | Sell | 2,602 | $24.00 |
| Jul 17, 2026 | BARRETT MICHAEL G.director, officer: CEO | Option | 38,596 | $5.80 |
| Jul 17, 2026 | BARRETT MICHAEL G.director, officer: CEO | Sell | 38,596 | $20.35 |
| Jul 14, 2026 | Caine Pauldirector | Sell | 5,000 | $20.64 |
| Jul 9, 2026 | Buonasera Davidofficer: CHIEF TECHNOLOGY OFFICER | Sell | 1,224 | $21.00 |
Source: MGNI SEC Form 4 filings, latest Aug 28, 2026. For informational purposes only — not investment advice.
Institutional activity (13F)
How institutions changed their MGNI positions over the last 6 months (SEC Form 13F).
Increased
228
New positions
110
Reduced
179
Sold out
37
Largest moves
| Institution | Action | Shares | Filed |
|---|---|---|---|
| BlackRock, Inc. | Increased | 12.7M | Aug 7, 2026 |
| BLACKROCK, INC. | Increased | 11.7M | May 13, 2026 |
| WELLINGTON MANAGEMENT GROUP LLP | Increased | 9.2M | May 15, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | Increased | 8.2M | Aug 13, 2026 |
| FMR LLC | Increased | 7.8M | Aug 13, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | New Position | 7.7M | May 8, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | Increased | 6.2M | Aug 13, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 6.2M | May 15, 2026 |
| WELLINGTON MANAGEMENT GROUP LLP | Reduced | 6.0M | Aug 14, 2026 |
| DIMENSIONAL FUND ADVISORS LP | Increased | 5.3M | Aug 11, 2026 |
| CAPITAL RESEARCH GLOBAL INVESTORS | Reduced | 5.0M | May 13, 2026 |
| Boston Partners | Increased | 5.0M | Aug 4, 2026 |
| BOSTON PARTNERS | Increased | 4.7M | May 11, 2026 |
| AMERICAN CENTURY COMPANIES INC | Reduced | 4.6M | May 15, 2026 |
| AMERICAN CENTURY COMPANIES INC | Reduced | 4.6M | Aug 12, 2026 |
Source: SEC Form 13F filings. For informational purposes only — not investment advice.