Atara Biotherapeutics, Inc. (ATRA) has 247 open-market insider trades by 30 insiders since 2014. Over the last six months insiders net bought $2.5M. The most active filer is Isaac E. Ciechanover, CEO.
| Name | Title | Tier | Trades | Value | Last Trade |
|---|---|---|---|---|---|
| Isaac E. Ciechanover | CEO | — | 64 | $20.1M | 2019-05-30 |
| Mitchall G. Clark | VP | — | 9 | $10.1M | 2018-05-18 |
| Joel S. Marcus | Dir | — | 6 | $7.5M | 2019-03-15 |
| Christopher Haqq | VP | — | 20 | $6.2M | 2019-02-15 |
| EcoR1 Capital, LLC | 10% Owner | — | 1 | $4.7M | 2026-05-07 |
| Panacea Innovation Ltd | 10% Owner | — | 2 | $3.8M | 2026-05-07 |
| John McGrath | CFOVP | — | 11 | $3.6M | 2018-03-20 |
| Gad Soffer | Dir | — | 16 | $3.0M | 2026-09-04 |
| Kathleen K. Schoemaker | 10% | — | 1 | $2.7M | 2014-10-21 |
| Isaac E. Ciechanover | CEO | — | 5 | $2.5M | 2019-05-30 |
| Insider | Title | Type | Value | Date |
|---|---|---|---|---|
| Gad Soffer | Director | Buy | $1000K | 2026-09-04 |
| AnhCo Nguyen | CEO & President | Sell | $41K | 2026-08-17 |
| AnhCo Nguyen | CEO & President | Sell | $48K | 2026-05-18 |
| Yanina Grant-Huerta | CAO | Sell | $22K | 2026-05-18 |
| EcoR1 Capital, LLC | 10% Owner | Buy | $4.7M | 2026-05-07 |
| Panacea Innovation Ltd | 10% Owner | Sell | $3.2M |
Companies that share insiders with ATRA, and sector peers with recent insider buying. Related by who files, not by how the stocks move.
| 2026-05-07 |
| AnhCo Nguyen | President | Sell | $15K | 2026-03-02 |
| Yanina Grant-Huerta | Chief Accounting Officer | Sell | $11K | 2026-03-02 |
| James Huang | Director & 10% | Sell | $489K | 2026-01-12 |
| Yanina Grant-Huerta | Chief Accounting Officer | Sell | $24K | 2025-11-17 |
| AnhCo Nguyen | President | Sell | $38K | 2025-11-17 |
| AnhCo Nguyen | President | Sell | $34K | 2025-08-18 |
| Yanina Grant-Huerta | Chief Accounting Officer | Sell | $21K | 2025-08-18 |
| Panacea Innovation Ltd | Director & 10% Owner | Buy | $670K | 2025-08-15 |
| James Huang | Director & 10% Owner | Buy | $373K | 2025-07-17 |