MGNI (Magnite, Inc. Common Stock)

Insider Trading Activity

Every open-market purchase and sale reported by MGNI officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.

Form 4 Filings
50
most recent
Open-Market Buys
0
code P
Sales
19
code S
Reporting Insiders
23
current holders
MGNI — Recent Form 4 Transactions (latest 2026-09-10)
FiledInsiderRole TypeSharesValue
2026-09-10 Katie Seitz Evans See Remarks MIXED
2026-09-03 David Buonasera CHIEF TECHNOLOGY OFFICER Sell
2026-08-28 Sarah Patricia Harden Director Sell
2026-08-18 Katie Seitz Evans See Remarks F
2026-08-18 David Day CHIEF FINANCIAL OFFICER F
2026-08-18 Aaron Saltz CHIEF LEGAL OFFICER F
2026-08-18 Sean Patrick Buckley See Remarks MIXED
2026-08-18 David Buonasera CHIEF TECHNOLOGY OFFICER F
2026-08-18 Paul Caine Director Sell
2026-08-18 Brian Gephart CHIEF ACCOUNTING OFFICER F
2026-08-18 MICHAEL G. BARRETT CEO F
2026-08-14 David Day CHIEF FINANCIAL OFFICER G
2026-08-12 Paul Caine Director Sell
2026-08-12 Brian Gephart CHIEF ACCOUNTING OFFICER Sell
2026-08-12 Rachel Lam Director Sell
2026-08-07 David Buonasera CHIEF TECHNOLOGY OFFICER Sell
2026-08-07 Katie Seitz Evans See Remarks MIXED
2026-08-07 Sean Patrick Buckley See Remarks MIXED
2026-08-07 MICHAEL G. BARRETT CEO MIXED
2026-08-07 Douglas S Knopper Director Sell
2026-08-07 Douglas S Knopper Director Sell
2026-08-07 David Buonasera CHIEF TECHNOLOGY OFFICER Sell
2026-08-07 Katie Seitz Evans See Remarks MIXED
2026-08-07 Sean Patrick Buckley See Remarks MIXED
2026-08-07 MICHAEL G. BARRETT CEO MIXED
2026-07-17 MICHAEL G. BARRETT CEO MIXED
2026-07-14 Paul Caine Director Sell
2026-07-09 Sean Patrick Buckley See Remarks Sell
2026-07-09 David Buonasera CHIEF TECHNOLOGY OFFICER Sell
2026-07-02 David Buonasera CHIEF TECHNOLOGY OFFICER Sell
2026-07-01 MICHAEL G. BARRETT CEO MIXED
2026-06-18 Sean Patrick Buckley See Remarks Sell
2026-06-17 Douglas S Knopper Director Sell
2026-06-17 David Buonasera CHIEF TECHNOLOGY OFFICER Sell
2026-06-17 MICHAEL G. BARRETT CEO MIXED
2026-06-10 Rachel Lam Director A
2026-06-10 Robert F Spillane Director A
2026-06-10 DAVID T. PEARSON Director MIXED
2026-06-10 Diane Yu Director A
2026-06-10 Paul Caine Director A
2026-06-10 Sarah Patricia Harden Director A
2026-06-10 Douglas S Knopper Director MIXED
2026-06-10 James Rossman Director A
2026-06-03 David Buonasera CHIEF TECHNOLOGY OFFICER Sell
2026-05-21 Robert F Spillane Director Sell
2026-05-19 Sean Patrick Buckley President, Revenue F
2026-05-19 MICHAEL G. BARRETT CEO F
2026-05-19 Brian Gephart CHIEF ACCOUNTING OFFICER F
2026-05-19 Aaron Saltz CHIEF LEGAL OFFICER F
2026-05-19 Katie Seitz Evans President, Operations F
MGNI — Current Insider Holders
InsiderRole Shares HeldValue
See Remarks 485,636
Chief Technology Officer 473,763
CHIEF FINANCIAL OFFICER 452,861
CEO 392,670
CHIEF PRODUCT OFFICER 388,425
Chief Revenue Officer, DV+ 311,083
See Remarks 295,819
CHIEF LEGAL OFFICER 264,389
CHIEF TECHNOLOGY OFFICER 246,320
Director 230,620
See remarks 213,207
Chief Technology Officer 191,071
Chief Accounting Officer 178,129
Director 149,901
Director 119,090
Director 114,751
Director 114,218
Director 107,477
CHIEF ACCOUNTING OFFICER 102,328
Director 89,767
Director 88,473
Director 81,279
Director 57,715
How to read Form 4 activity

Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.

Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.

Full filing history and per-insider positions are on the MGNI quote page; the site-wide leaderboard is on the insider transactions hub.