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MGNI Insider Trading: MAGNITE, INC. Insider Buys and Sells · https://wallstpal.com/stock/mgni/insider-trading/ · saved 2026-10-28

About this page

Insider trades reported on SEC Form 4: when the people who run a company buy or sell its shares with their own money.

How to read it

Form 4
The form a company insider (officer, director or owner of more than 10%) must file with the SEC within two business days of buying or selling the company's shares.
Buy (P) and Sell (S)
Open-market purchases and sales. Gifts, option exercises and automatic tax withholding are left out because they say little about what the insider thinks.
Value
Shares times price, as reported on the filing.
10b5-1
A trade made under a plan set up in advance. Planned sales are common and usually say less than an unplanned purchase.
Late filing
A Form 4 filed more than two business days after the trade.
Vs. S&P 500
How the stock did after the trade minus how the overall market did in the same weeks.

A real example

In January 2016, when bank stocks were falling, JPMorgan Chase CEO Jamie Dimon bought 500,000 JPMorgan shares with his own money, worth about $26 million. His Form 4 made the purchase public within days, and investors read it as a strong sign of confidence.

Explain it like I'm 13

If the coach of a team bets his own allowance that his team will win, that tells you something. A Form 4 is the note a company boss must hand in whenever he buys or sells his own company's shares, so everyone can see it.

Data from public SEC filings and congressional reports. Information, not investment advice. Check every number against the filing linked on the page.

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Insider tradingForm 4

MAGNITE, INC. (MGNI) Insider Trading

38 open-market trades reported since Jun 17, 2026: 0 purchases worth $0 and 38 sales worth $25.4M.

By insider

InsiderRoleBuysBoughtSellsSoldLatest
Paul CaineDirector0$06$1.04MOct 14, 2026
Douglas S. KnopperDirector0$03$2.51MSep 18, 2026
Robert F. SpillaneDirector0$01$246KSep 16, 2026
David BuonaseraCTO0$09$819KSep 16, 2026
Aaron SaltzGeneral Counsel0$01$936KSep 11, 2026
Katie Seitz EvansSee Remarks0$04$1.84MSep 11, 2026
Sarah Patricia HardenDirector0$02$1.15MAug 28, 2026
Sean Patrick BuckleySee Remarks0$05$2.69MAug 18, 2026
Brian GephartCAO0$01$308KAug 12, 2026
Rachel LamDirector0$01$242KAug 12, 2026
Michael G. BarrettCEO0$05$13.6MAug 7, 2026

All trades

MGNI insider trades
FiledTradedInsiderRoleTypeSharesPrice ($)ValueHolding3 mo. afterFiling
Oct 14Oct 12Paul CaineDirectorDirector▼ SELL10b5-112,50025.29$316K−9.1%Form 4 ↗
Sep 18Sep 17Douglas S. KnopperDirectorDirector▼ SELL10b5-137,33726.28$981K−42%Form 4 ↗
Sep 18Sep 17Paul CaineDirectorDirector▼ SELL10b5-17,50026.50$199K−5.2%Form 4 ↗
Sep 16Sep 14Robert F. SpillaneDirectorDirector▼ SELL10,36323.76$246K−15%Form 4 ↗
Sep 16Sep 14David BuonaseraCTOCTO▼ SELL10b5-11,16524.00$28K−0.5%Form 4 ↗
Sep 11Sep 10Aaron SaltzGeneral CounselGeneral Counsel▼ SELL10b5-140,00023.41$936K−15%Form 4 ↗
Sep 11Sep 11Katie Seitz EvansSee RemarksSee Remarks▼ SELL10b5-113,99724.00$336K−3.1%Form 4 ↗
Sep 11Sep 10Paul CaineDirectorDirector▼ SELL10b5-15,00023.53$118K−3.3%Form 4 ↗
Sep 10Sep 8Katie Seitz EvansSee RemarksSee Remarks▼ SELL10b5-132,28523.63$763K−6.5%Form 4 ↗
Sep 10Sep 9Katie Seitz EvansSee RemarksSee Remarks▼ SELL10b5-111,10023.46$260K−2.4%Form 4 ↗
Sep 3Sep 1David BuonaseraCTOCTO▼ SELL10b5-15,37123.42$126K−2.1%Form 4 ↗
Sep 3Sep 2David BuonaseraCTOCTO▼ SELL10b5-11,04325.00$26K−0.4%Form 4 ↗
Aug 28Aug 26Sarah Patricia HardenDirectorDirector▼ SELL10b5-130,55023.31$712K−19%Form 4 ↗
Aug 28Aug 28Sarah Patricia HardenDirectorDirector▼ SELL10b5-118,43624.00$442K−14%Form 4 ↗
Aug 18Aug 17Sean Patrick BuckleySee RemarksSee Remarks▼ SELL10b5-18,27124.31$201K−2.7%Form 4 ↗
Aug 18Aug 14Paul CaineDirectorDirector▼ SELL10b5-17,50025.00$188K−4.8%Form 4 ↗
Aug 18Aug 18Sean Patrick BuckleySee RemarksSee Remarks▼ SELL10b5-12,75925.00$69K−0.9%Form 4 ↗
Aug 12Aug 10Brian GephartCAOCAO▼ SELL12,47924.68$308K−11%Form 4 ↗
Aug 12Aug 10Rachel LamDirectorDirector▼ SELL10,00024.16$242K−4.2%Form 4 ↗
Aug 12Aug 10Paul CaineDirectorDirector▼ SELL10b5-15,00024.35$122K−3.1%Form 4 ↗
Aug 7Aug 6Michael G. BarrettCEOCEO▼ SELL10b5-1293,96822.72$6.68M−42%Form 4 ↗
Aug 7Aug 6Sean Patrick BuckleySee RemarksSee Remarks▼ SELL10b5-167,17924.49$1.65M−18%Form 4 ↗
Aug 7Aug 6Douglas S. KnopperDirectorDirector▼ SELL10b5-137,33722.72$848K−30%Form 4 ↗
Aug 7Aug 6Katie Seitz EvansSee RemarksSee Remarks▼ SELL10b5-120,00024.00$480K−3.9%Form 4 ↗
Aug 7Aug 6David BuonaseraCTOCTO▼ SELL10b5-17,64923.46$179K−2.8%Form 4 ↗
Jul 17Jul 15Michael G. BarrettCEOCEO▼ SELL10b5-138,59620.35$785K−8.7%Form 4 ↗
Jul 14Jul 10Paul CaineDirectorDirector▼ SELL10b5-15,00020.64$103K−3.0%Form 4 ↗
Jul 9Jul 7Sean Patrick BuckleySee RemarksSee Remarks▼ SELL10b5-119,23321.03$404K−5.1%Form 4 ↗
Jul 9Jul 7David BuonaseraCTOCTO▼ SELL10b5-11,22421.00$26K−0.5%Form 4 ↗
Jul 2Jul 1David BuonaseraCTOCTO▼ SELL10b5-19,37620.00$188K−3.4%Form 4 ↗
Jul 1Jun 29Michael G. BarrettCEOCEO▼ SELL10b5-175,00019.50$1.46M−16%Form 4 ↗
Jun 18Jun 17Sean Patrick BuckleySee RemarksSee Remarks▼ SELL10b5-119,23319.00$365K−4.9%Form 4 ↗
Jun 17Jun 15Michael G. BarrettCEOCEO▼ SELL10b5-1178,59616.59$2.96M−31%Form 4 ↗
Jun 17Jun 16Michael G. BarrettCEOCEO▼ SELL10b5-1100,00017.50$1.75M−20%Form 4 ↗
Jun 17Jun 16Douglas S. KnopperDirectorDirector▼ SELL10b5-137,33718.10$676K−23%Form 4 ↗
Jun 17Jun 16David BuonaseraCTOCTO▼ SELL10b5-111,23318.00$202K−3.9%Form 4 ↗
Jun 17Jun 17David BuonaseraCTOCTO▼ SELL10b5-11,40919.00$27K−0.5%Form 4 ↗
Jun 17Jun 15David BuonaseraCTOCTO▼ SELL10b5-11,05717.00$18K−0.4%Form 4 ↗
Source: SEC Form 4 filings, retrieved Oct 28, 2026. How we read filings