ATRA Insider Trading Activity and SEC Form 4 Filings
ATRA insider trading summary
Over the past 12 months, insiders at Atara Biotherapeutics, Inc. (ATRA) reported 20 sales worth $7.5M by 4 insiders and 2 open-market purchases worth $5.7M by 2 insiders on SEC Form 4. Net insider selling was $1.8M.
Latest ATRA insider buys and sells
| Date | Insider | Role | Type | Value |
|---|---|---|---|---|
| Sep 4, 2026 | Brian N Cherry | Insider | Buy | $1000K (104,166 @ $9.60) |
| Aug 17, 2026 | AnhCo Nguyen | President and CEO | Sell | $41K (5,062 @ $8.08) |
| May 18, 2026 | Yanina Grant-Huerta | Chief Accounting Officer | Sell | $22K (2,414 @ $9.13) |
| May 18, 2026 | AnhCo Nguyen | President and CEO | Sell | $48K (5,241 @ $9.13) |
| May 7, 2026 | EcoR1 Capital, LLC | 10% Owner | Buy | $4.7M (507,407 @ $9.35) |
| May 7, 2026 | James Huang | Insider | Sell | $3.2M (313,446 @ $10.10) |
| May 7, 2026 | Panacea Innovation Ltd | Insider | Sell | $3.2M (313,446 @ $10.10) |
| Mar 2, 2026 | Yanina Grant-Huerta | Chief Accounting Officer | Sell | $2K (377 @ $5.08) |
| Mar 2, 2026 | Yanina Grant-Huerta | Chief Accounting Officer | Sell | $122 (24 @ $5.08) |
| Mar 2, 2026 | AnhCo Nguyen | President and CEO | Sell | $1K (198 @ $5.08) |
Source: SEC Form 4 filings. Open-market purchases (code P) and sales (code S) only; option exercises, grants and gifts are excluded.