Atara Biotherapeutics, Inc. (ATRA) is a publicly traded company in the Unknown sector. Across all available filings, 39 corporate insiders have executed 1016 transactions totaling $69.3M, demonstrating a bearish sentiment with -$55.8M in net insider flow. The most recent transaction on Jan 12, 2026 involved a sale of 80,554 shares valued at $489.0K.
No significant insider buying has been recorded for ATRA in the recent period.
No significant insider selling has been recorded for ATRA in the recent period.
Based on recent SEC filings, insider sentiment for ATRA is bearish with an Insider Alignment Score of 10/100 and a net flow of -$55.8M. Insiders are reducing their positions, though this can be driven by factors unrelated to company outlook.
Insider trading at Atara Biotherapeutics, Inc. (ATRA) refers to stock transactions made by corporate insiders—executives, directors, and beneficial owners holding more than 10% of the company's shares. These individuals have access to material non-public information and are required by law to report their trades to the SEC within two business days. Currently, 39 insiders are actively trading ATRA stock, having executed 1016 transactions in the past 90 days. The most active insider is Isaac E. Ciechanover (Executive), who has made 350 transactions totaling $31.1M.
Get notified when executives and directors at ATRA file new Form 4 transactions
Date | Insider | Title | Type | Shares | Price | Value | Flags |
|---|---|---|---|---|---|---|---|
| Jan 12, 2026 | Ltd Panacea Innovation | Executive | Sale | 80,554 | $6.07 | $489.0K | |
| Nov 28, 2025 | Ltd Panacea Innovation | Executive | Option Exercise | 48,737 | $N/A | $0 | |
| Nov 28, 2025 | Ltd Panacea Innovation | Executive | Payment | 1 | $14.03 | $14 | |
| Nov 17, 2025 | Grant-huerta Yanina | Executive | Sale | 85 | $13.19 | $1.1K | |
| Nov 17, 2025 | Grant-huerta Yanina | Executive | Sale | 74 | $13.19 | $976 | |
| Nov 17, 2025 | Grant-huerta Yanina | Executive | Sale | 1,645 | $13.19 | $21.7K | |
| Nov 17, 2025 | Nguyen Anhco | Executive | Sale | 2,859 | $13.19 | $37.7K | |
| Nov 17, 2025 | Nguyen Anhco | Executive | Sale | 56 | $13.19 | $739 | |
| Aug 18, 2025 | Grant-huerta Yanina | Executive | Sale | 1,668 | $11.61 | $19.4K | |
| Aug 18, 2025 | Grant-huerta Yanina | Executive | Sale | 86 | $11.61 | $998 | |
| Aug 18, 2025 | Grant-huerta Yanina | Executive | Sale | 55 | $11.61 | $639 | |
| Aug 18, 2025 | Nguyen Anhco | Executive | Sale | 1,281 | $11.62 | $14.9K | |
| Aug 18, 2025 | Nguyen Anhco | Executive | Sale | 1,620 | $11.62 | $18.8K | |
| Aug 18, 2025 | Nguyen Anhco | Executive | Sale | 57 | $11.61 | $662 | |
| Aug 15, 2025 | Ltd Panacea Innovation | Executive | Purchase | 55,000 | $12.19 | $670.5K | Large |
| TYPE | COUNT | VALUE | % |
|---|---|---|---|
Sale(S) | 654 | $62.6M | 72.2% |
Payment(F) | 34 | $12.5M | 14.4% |
Purchase(P) | 21 | $6.8M | 7.8% |
Exercise(M) | 152 | $4.8M | 5.6% |
Award(A) | 124 | $0 | 0.0% |
Gift(G) | 3 | $0 | 0.0% |
Other(J) | 17 | $0 | 0.0% |
Conversion(C) | 11 | $0 | 0.0% |
Insider selling pressure at Atara Biotherapeutics, Inc. has increased, with 39 insiders executing 1016 transactions across all time. Total sales of $62.6M significantly outpace purchases of $6.8M, resulting in a net outflow of $55.8M. This selling activity appears largely discretionary, which may warrant closer attention from investors.