As of the latest Form 4 filed Jul 9, 2026.
What Magnite Inc insiders — officers, directors and 10% owners — have bought and sold in their own stock, straight from their SEC Form 4 filings. Values are shares × the reported transaction price where both are disclosed.
Buys plotted up, sells down; bar height is the disclosed dollar value (shares × reported price). Our Form 4 history is only complete from mid-2026, so early months are sparse — the series fills in as more filings land. Open-market purchases and sales only.
Newest filing first — the 26 most recent filings for MGNI.
| Filed | Trade date | Insider | Transaction | Shares | Price | Value | 10b5-1 | Filing |
|---|---|---|---|---|---|---|---|---|
| 2026-07-09 | 2026-07-07 | Buonasera David CHIEF TECHNOLOGY OFFICER | SSale | −1.22K | $21.00 | $25.7K | Yes (planned) | Form 4 ↗ |
| 2026-07-09 | 2026-07-07 | Buckley Sean Patrick See Remarks | SSale | −19.2K | $21.03 | $404K | Yes (planned) | Form 4 ↗ |
| 2026-07-02 | 2026-07-01 | Buonasera David CHIEF TECHNOLOGY OFFICER | SSale | −9.38K | $20.00 | $188K | Yes (planned) | Form 4 ↗ |
| 2026-07-01 | 2026-06-29 | BARRETT MICHAEL G. CEO | SSale | −75.0K | $19.50 | $1.46M | Yes (planned) | Form 4 ↗ |
| 2026-07-01 | 2026-06-29 | BARRETT MICHAEL G., CEO | MExercise | +75.0K | $5.80 | $435K | Yes (planned) | Form 4 ↗ |
| 2026-06-18 | 2026-06-17 | Buckley Sean Patrick See Remarks | SSale | −19.2K | $19.00 | $365K | Yes (planned) | Form 4 ↗ |
| 2026-06-17 | 2026-06-17 | Buonasera David CHIEF TECHNOLOGY OFFICER | SSale | −1.41K | $19.00 | $26.8K | Yes (planned) | Form 4 ↗ |
| 2026-06-17 | 2026-06-16 | Knopper Douglas S Director | SSale | −37.3K | $18.10 | $676K | Yes (planned) | Form 4 ↗ |
| 2026-06-17 | 2026-06-16 | Buonasera David CHIEF TECHNOLOGY OFFICER | SSale | −11.2K | $18.00 | $202K | Yes (planned) | Form 4 ↗ |
| 2026-06-17 | 2026-06-16 | BARRETT MICHAEL G. CEO | SSale | −100K | $17.50 | $1.75M | Yes (planned) | Form 4 ↗ |
| 2026-06-17 | 2026-06-16 | BARRETT MICHAEL G., CEO | MExercise | +100K | $5.80 | $580K | Yes (planned) | Form 4 ↗ |
| 2026-06-17 | 2026-06-15 | Buonasera David CHIEF TECHNOLOGY OFFICER | SSale | −1.06K | $17.00 | $18.0K | Yes (planned) | Form 4 ↗ |
| 2026-06-17 | 2026-06-15 | BARRETT MICHAEL G. CEO | SSale | −179K | $16.59 | $2.96M | Yes (planned) | Form 4 ↗ |
| 2026-06-17 | 2026-06-15 | BARRETT MICHAEL G., CEO | MExercise | +179K | $5.80 | $1.04M | Yes (planned) | Form 4 ↗ |
| 2026-06-10 | 2026-06-10 | Knopper Douglas S Director | SSale | −10.8K | $15.73 | $169K | Yes (planned) | Form 4 ↗ |
| 2026-06-10 | 2026-06-10 | PEARSON DAVID T. Director | SSale | −10.8K | $15.65 | $168K | Yes (planned) | Form 4 ↗ |
| 2026-06-10 | 2026-06-08 | Caine Paul Director | AAward | +13.8K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-10 | 2026-06-08 | Yu Diane Director | AAward | +13.8K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-10 | 2026-06-08 | Spillane Robert F Director | AAward | +13.8K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-10 | 2026-06-08 | Harden Sarah Patricia Director | AAward | +13.8K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-10 | 2026-06-08 | Knopper Douglas S Director | AAward | +13.8K | $0.00 | $0.00 | Yes (planned) | Form 4 ↗ |
| 2026-06-10 | 2026-06-08 | Rossman James Director | AAward | +13.8K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-10 | 2026-06-08 | Lam Rachel Director | AAward | +13.8K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-10 | 2026-06-08 | PEARSON DAVID T. Director | AAward | +13.8K | $0.00 | $0.00 | Yes (planned) | Form 4 ↗ |
| 2026-06-03 | 2026-06-01 | Buonasera David CHIEF TECHNOLOGY OFFICER | SSale | −1.41K | $15.00 | $21.1K | Yes (planned) | Form 4 ↗ |
| 2026-05-21 | 2026-05-19 | Spillane Robert F Director | SSale | −10.0K | $13.33 | $133K | No | Form 4 ↗ |
Insiders — a company’s officers, directors and holders of more than 10% of its stock — must report any trade in that stock to the SEC on a Form 4 within two business days. Each row here is one transaction from those filings.
The transaction code tells you what happened: Purchase (P) and Sale (S) are open-market trades — the ones markets watch most; Award (A) is a granted stock or unit, Option exercise (M) converts options into shares, and Gift (G) is a transfer for no consideration. Awards, exercises and gifts are largely compensation or administrative, not a directional bet.
One caveat on sales: many are made under a Rule 10b5-1 plan scheduled months in advance, so a sale is not automatically a bearish signal. Insider activity is a noisy input — read it alongside the filings, not on its own.
See also MGNI’s full analysis or the market-wide insider trading feed. The tabs above jump to MGNI’s other SEC data.
Source: SEC Form 4 filings for MGNI, parsed from EDGAR. Transaction prices are as reported in the filing — SEC public-domain data, not market quotes. Values are shares × reported price where both are disclosed; grants and gifts often carry no price. A delayed record of what insiders reported, not a live position or a recommendation.
Research and education only — not financial advice. TENKis not a registered investment adviser or broker-dealer and gives no personalized advice. Every call is impersonal — identical for all users, generated on a schedule from SEC filings plus a delayed/third-party price feed — may be wrong or out of date, and is not a recommendation to buy or sell any security. The operator and an affiliated trading operation may hold or trade the securities TENK rates; see Disclosures. Past performance does not guarantee future results. Do your own research.