// company-profile
Atara Biotherapeutics, Inc.
ATRA// activity-summary
Recent insider activity is bullish. Over the last 30 days, 4 insiders purchased shares. Buying was led by Cherry Brian N.
// 90-day insight
Over the last 90 days, Atara Biotherapeutics, Inc. insiders bought $4.7M (5 transactions) and sold $3.2M (3 transactions).
- Most active insider: EcoR1 Capital, LLC with 1 transaction totaling $4.7M.
- Largest single purchase: $4.7M by EcoR1 Capital, LLC on May 7, 2026.
Activity skews bullish — buys outpace sales.
Institutional Ownership
Top 13F-HR holders of Atara Biotherapeutics, Inc. as of 2026-03-31
Data source: SEC Form 13F-HR filings. Joined with insider activity above — see who's loading up institutionally while insiders are trading. Full 13F-HR API →
Insider Transactions
Sourced from SEC EDGAR Form 4 filings. Updated hourly.
| Date | Insider | Company | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Jun 11, 2026 | Cherry Brian N | ATRA | Award | 24,000 | $0.00 | $0K |
| Jun 9, 2026 | HEIDEN WILLIAM K | ATRA | Award | 12,000 | $0.00 | $0K |
| Jun 9, 2026 | Ciongoli Gregory Austin | ATRA | Award | 12,000 | $0.00 | $0K |
| Jun 9, 2026 | Fust Matthew K | ATRA | Award | 12,000 | $0.00 | $0K |
| May 18, 2026 | Nguyen AnhCo | ATRA | Sale | 5,241 | $9.13 | $48K |
45 more transactions hidden
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