MGNI
MAGNITE, INC.
NASDAQ · Communication Services · Advertising Agencies · US
$25.15
−1.87%0
Insider buys (3m)
33
Insider sells (3m)
-$19.1M
Net value (3m)
+45.5%
Price return (3m)
Form 4 filings
| Date | Insider | Activity | Shares | Price |
|---|---|---|---|---|
| Sep 18, 2026 | Caine Paul · director | Sale | 7,500 | $27 |
| Sep 18, 2026 | Knopper Douglas S · director | Sale | 37,337 | $26 |
| Sep 16, 2026 | Spillane Robert F · director | Sale | 10,363 | $24 |
| Sep 16, 2026 | Spillane Robert F · director | M-Exempt | 10,363 | $5.17 |
| Sep 16, 2026 | Buonasera David · officer: CHIEF TECHNOLOGY OFFICER | Sale | 1,165 | $24 |
| Sep 11, 2026 | Caine Paul · director | Sale | 5,000 | $24 |
| Sep 11, 2026 | Evans Katie Seitz · officer: See Remarks | Sale | 13,997 | $24 |
| Sep 11, 2026 | Saltz Aaron · officer: CHIEF LEGAL OFFICER | Sale | 40,000 | $23 |
| Sep 10, 2026 | Evans Katie Seitz · officer: See Remarks | Sale | 11,100 | $23 |
| Sep 10, 2026 | Evans Katie Seitz · officer: See Remarks | Sale | 32,285 | $24 |
| Sep 10, 2026 | Evans Katie Seitz · officer: See Remarks | M-Exempt | 13,546 | $5.16 |
| Sep 3, 2026 | Buonasera David · officer: CHIEF TECHNOLOGY OFFICER | Sale | 5,371 | $23 |
| Sep 3, 2026 | Buonasera David · officer: CHIEF TECHNOLOGY OFFICER | Sale | 1,043 | $25 |
| Aug 28, 2026 | Harden Sarah Patricia · director | Sale | 30,550 | $23 |
| Aug 28, 2026 | Harden Sarah Patricia · director | Sale | 18,436 | $24 |
| Aug 18, 2026 | Caine Paul · director | Sale | 7,500 | $25 |
| Aug 18, 2026 | Evans Katie Seitz · officer: See Remarks | F-InKind | 11,204 | $25 |
| Aug 18, 2026 | Gephart Brian · officer: CHIEF ACCOUNTING OFFICER | F-InKind | 3,789 | $25 |
| Aug 18, 2026 | BARRETT MICHAEL G. · director, officer: CEO | F-InKind | 10,404 | $25 |
| Aug 18, 2026 | Day David · officer: CHIEF FINANCIAL OFFICER | F-InKind | 14,170 | $25 |
| Aug 18, 2026 | Buckley Sean Patrick · officer: See Remarks | Sale | 8,271 | $24 |
| Aug 18, 2026 | Saltz Aaron · officer: CHIEF LEGAL OFFICER | F-InKind | 5,627 | $25 |
| Aug 18, 2026 | Buckley Sean Patrick · officer: See Remarks | F-InKind | 11,715 | $25 |
| Aug 18, 2026 | Buonasera David · officer: CHIEF TECHNOLOGY OFFICER | F-InKind | 8,102 | $25 |
| Aug 18, 2026 | Buckley Sean Patrick · officer: See Remarks | Sale | 2,759 | $25 |
| Aug 12, 2026 | Gephart Brian · officer: CHIEF ACCOUNTING OFFICER | Sale | 12,479 | $25 |
| Aug 12, 2026 | Lam Rachel · director | Sale | 10,000 | $24 |
| Aug 12, 2026 | Caine Paul · director | Sale | 5,000 | $24 |
| Aug 7, 2026 | BARRETT MICHAEL G. · director, officer: CEO | M-Exempt | 293,968 | $5.80 |
| Aug 7, 2026 | Evans Katie Seitz · officer: See Remarks | Sale | 20,000 | $24 |
Institutional positioning
13F filings over the trailing two quarters
New 110Increased 226Reduced 179Sold out 36
| Filer | Action | Shares | Filed |
|---|---|---|---|
| BlackRock, Inc. | Increased | 12,713,156 | Aug 7, 2026 |
| BLACKROCK, INC. | Increased | 11,657,496 | May 13, 2026 |
| WELLINGTON MANAGEMENT GROUP LLP | Increased | 9,191,077 | May 15, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | Increased | 8,197,286 | Aug 13, 2026 |
| FMR LLC | Increased | 7,759,426 | Aug 13, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | New Position | 7,726,205 | May 8, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | Increased | 6,225,195 | Aug 13, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 6,190,403 | May 15, 2026 |
| WELLINGTON MANAGEMENT GROUP LLP | Reduced | 6,044,492 | Aug 14, 2026 |
| DIMENSIONAL FUND ADVISORS LP | Increased | 5,260,132 | Aug 11, 2026 |
| CAPITAL RESEARCH GLOBAL INVESTORS | Reduced | 5,020,289 | May 13, 2026 |
| Boston Partners | Increased | 5,013,835 | Aug 4, 2026 |
| BOSTON PARTNERS | Increased | 4,719,863 | May 11, 2026 |
| AMERICAN CENTURY COMPANIES INC | Reduced | 4,626,816 | May 15, 2026 |
| AMERICAN CENTURY COMPANIES INC | Reduced | 4,622,736 | Aug 12, 2026 |
Insider activity from SEC Form 4; institutional positioning from 13F filings · Latest filing Sep 18, 2026