Summary
Updated Aug 30, 2026
Douglas S. Knopper is Director of MAGNITE, INC. (MGNI). 3 SEC Form 4 filings on record, most recently on 7 August 2026. Most recent open-market trade: sold $848K of MGNI on 7 August 2026. Lifetime open-market sales: $1.69M.
Recent Transactions
4Every recent SEC Form 4 transaction Douglas S. Knopper has reported, most recent first.
Other Insiders Active in the Same Stocks
Insiders who reported open-market trades in the last 12 months at the companies Douglas S. Knopper files at. Multiple unrelated insiders buying the same stock within a short window, cluster buying, has historically been one of the strongest Form 4 signals.
- Michael G. Barrett - $13.64M of MGNI open-market activity in the last 12 months
- Sean Patrick Buckley - $3.78M of MGNI open-market activity in the last 12 months
- Sarah Patricia Harden - $1.15M of MGNI open-market activity in the last 12 months
- Adam Lee Soroca - $1.02M of MGNI open-market activity in the last 12 months
- Brian Gephart - $992K of MGNI open-market activity in the last 12 months
- Paul Caine - $818K of MGNI open-market activity in the last 12 months
More Notable Insiders
Other corporate insiders with significant SEC Form 4 track records on InsiderAlpha:
Frequently Asked Questions
Who is Douglas S. Knopper?
Douglas S. Knopper is a corporate insider, tracked as Director of MAGNITE, INC. (MGNI). InsiderAlpha holds 3 primary Form 4 filings for them, the earliest from 2026, updated as new SEC EDGAR filings are processed.
How many SEC Form 4 filings has Douglas S. Knopper submitted recently?
3 primary Form 4 filings in the last 90 days, covering 1 company.
Has Douglas S. Knopper been buying or selling stock?
Recorded transactions: 0 open-market purchases and 3 open-market sales ($1.69M) across all tracked filings.
Where can I see all of Douglas S. Knopper's SEC filings?
All Form 4 filings, transaction values, and 10b5-1 plan flags are listed on this page and updated in real time as new SEC EDGAR filings are processed.
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