Knopper Douglas S, Insider at MAGNITE, INC., sold $169K of MGNI
This page documents an SEC Form 4 insider trading disclosure for $MGNI securities filed with the Securities and Exchange Commission. Section 16 of the Securities Exchange Act of 1934 mandates that corporate officers, directors, and beneficial owners of more than 10% of a company's registered equity securities must report their personal trades within two business days of execution. Insider transactions are closely monitored by market participants because insiders possess firsthand knowledge of company operations, financial condition, and near-term prospects. The transaction details below are drawn directly from the SEC EDGAR filing database and reflect the information as reported.
Transaction Details
| Insider | Knopper Douglas S |
|---|---|
| Title | Insider |
| Company | MAGNITE, INC. |
| Ticker | MGNI |
| Transaction Type | Sale |
| Transaction Date | 2026-06-10 |
| Shares Traded | 10,766 |
| Price Per Share | $15.73 |
| Total Value | $169K |
| Filed Date | 2026-06-10 |
| Accession Number | 0001193125-26-266370 |
Ownership Context
| Shares Owned After Transaction | 163,147 |
|---|---|
| Ownership Type | Direct |
SEC Filing
Accession: 0001193125-26-266370
Other Insider Trades — MGNI
| Insider | Title | Action | Value | Date |
|---|---|---|---|---|
| Evans Katie Seitz | See Remarks | traded | $103K | 2026-08-06 |
| Buckley Sean Patrick | See Remarks | traded | $399K | 2026-08-06 |
| Buckley Sean Patrick | See Remarks | sold | $442K | 2026-08-06 |
| Buckley Sean Patrick | See Remarks | sold | $1.2M | 2026-08-06 |
| BARRETT MICHAEL G. | CEO, Director | traded | $1.7M | 2026-08-06 |
| Buonasera David | CHIEF TECHNOLOGY OFFICER | sold | $95K | 2026-08-06 |
| BARRETT MICHAEL G. | CEO, Director | sold | $6.7M | 2026-08-06 |
| Buonasera David | CHIEF TECHNOLOGY OFFICER | sold | $22K | 2026-08-06 |
| Buonasera David | CHIEF TECHNOLOGY OFFICER | sold | $62K | 2026-08-06 |
| Evans Katie Seitz | See Remarks | sold | $480K | 2026-08-06 |
Other Trades by Knopper Douglas S
| Ticker | Company | Action | Value | Date |
|---|---|---|---|---|
| MGNI | MAGNITE, INC. | sold | $848K | 2026-08-06 |
| MGNI | MAGNITE, INC. | sold | $676K | 2026-06-16 |
| MGNI | MAGNITE, INC. | traded | — | 2026-06-08 |
Full Ticker Profile
View all insider trades, dark pool activity, congressional filings, and the Whisper Score for MGNI — MAGNITE, INC. →
Whisper Score — MGNI
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Data sourced from SEC Form 4 insider trading filings. Transaction details are as reported to the Securities and Exchange Commission. This page does not constitute financial advice. StonkWhisper presents public records — it does not verify or guarantee the accuracy of SEC filings.
Last updated: August 12, 2026 at 07:17 UTC