Douglas S Knopper
CIK 1350876 · last filed 2026-08-07
Douglas S Knopper is a corporate insider who has filed 24 SEC Form 4 insider transactions across 4 companies since 2007. The most recent filing shows the insider sold $848.3K of MGNI on Aug 7, 2026. Across all open-market trades the lifetime net is −$3.3M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $2.1M across reported positions.
"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.
$2.10M
4
24
-$3.28M
Filer Profile
708 THIRD AVENUE
NEW YORK, NY 10017
Holdings By Company
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| MGNI | Director | 88,473 | $23.77 | $2.10M | -$3.28M | 12 | 2026-08-07 |
| RUBI | Director | 2 | $1.51 | $3 | $0 | 1 | 2020-04-03 |
| Telaria, Inc. (TLRA) Delisted | Director | 84,757 | — | — | $0 | 3 | 2019-10-17 |
| MEDIALINK WORLDWIDE INC (MDLK) Delisted | Director | — | — | — | $0 | 3 | 2009-01-06 |
Recent Filings
24 filings| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2026-08-07 | MGNI | Sell (S) | −37,337 | -$848.3K | EDGAR |
| 2026-08-07 | MGNI | Sell (S) | −37,337 | -$848.3K | EDGAR |
| 2026-08-06 | MGNI | Notice (144) | −19,128 | -$395.4K | EDGAR |
| 2026-08-06 | MGNI | Notice (144) | −18,209 | -$376.4K | EDGAR |
| 2026-06-17 | MGNI | Sell (S) | −37,337 | -$675.8K | EDGAR |
| 2026-06-16 | MGNI | Notice (144) | −37,337 | -$625.4K | EDGAR |
| 2026-06-10 | MGNI | Notice (144) | −10,766 | -$170.2K | EDGAR |
| 2026-06-10 | MGNI | Mixed | +3,032 | -$169.3K | EDGAR |
| 2025-06-06 | MGNI | Grant (A) | +10,766 | $0 | EDGAR |
| 2024-06-13 | MGNI | Grant (A) | +14,061 | $0 | EDGAR |
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.