Over 12 months, Atara Biotherapeutics, Inc. saw more buying than selling from its insiders — purchases of about $5.7 million against sales of $3.9 million.
Biggest single buyer: EcoR1 Capital, LLC, 10% Owner, with roughly $4.7 million.
Zooming out by quarter: 2 quarters in a row of net buying by insiders. Insiders bought in 3 of the last 7 full quarters. 35 investment managers listed ATRA in their latest 13F filings (Q2 2026); more funds bought than sold.
| Filed | Insider | Role | Type | Shares | Price | Value | Source |
|---|---|---|---|---|---|---|---|
| Sep 4, 2026 | Cherry Brian N | Director | Buy | 104,166 | $9.60 | $1000K | SEC |
| Aug 26, 2026 | Nguyen AnhCo | CEO | Sell | 5,062 | $8.08 | $41K | SEC |
| May 20, 2026 | Nguyen AnhCo | CEO | Sell | 5,241 | $9.13 | $48K | SEC |
| May 20, 2026 | Grant-Huerta Yanina | Executive Officer | Sell | 2,414 | $9.13 | $22K | SEC |
| May 11, 2026 | Panacea Innovation Ltd | Director | Sell | 313,446 | $10.10 | $3.2M | SEC |
| May 11, 2026 | EcoR1 Capital, LLC | 10% Owner | Buy | 507,407 | $9.35 | $4.7M | SEC |
| Mar 4, 2026 | Grant-Huerta Yanina | Executive Officer | Sell | 377 | $5.08 | $2K | SEC |
| Mar 4, 2026 | Grant-Huerta Yanina | Executive Officer | Sell | 1,603 | $5.08 | $8K | SEC |
| Mar 4, 2026 | Grant-Huerta Yanina | Executive Officer | Sell | 24 | $5.08 | $122 | SEC |
| Mar 4, 2026 | Grant-Huerta Yanina | Executive Officer | Sell | 100 | $5.08 | $508 | SEC |
| Mar 4, 2026 | Nguyen AnhCo | CEO | Sell | 58 | $5.08 | $295 | SEC |
| Mar 4, 2026 | Nguyen AnhCo | CEO | Sell | 1,298 | $5.09 | $7K | SEC |
| Mar 4, 2026 | Nguyen AnhCo | CEO | Sell | 198 | $5.08 | $1K | SEC |
| Mar 4, 2026 | Nguyen AnhCo | CEO | Sell | 1,442 | $5.09 | $7K | SEC |
| Jan 14, 2026 | Huang James | Director | Sell | 80,554 | $6.07 | $489K | SEC |
In the last 12 months Atara Biotherapeutics, Inc. insiders made open-market purchases worth about $5.7 million and sales worth about $3.9 million. Data comes from SEC Form 4 filings, updated every 30 minutes on CapitalSnitch.
The most recent open-market insider trade in ATRA was filed on 2026-09-04.
35 investment managers reported holding ATRA in SEC Form 13F filings for Q2 2026.
No congressional trades in ATRA were reported in the past two years. The full list is free on CapitalSnitch.
Public-record data for research and education, not investment advice. Insider sales are often pre-planned (10b5-1). Congress data: Data derived from public disclosures filed under the Ethics in Government Act and the STOCK Act, republished free for public transparency and news reporting. Disclosures may lag the trade by 45 days or more and show amounts only as ranges. This data may not be used for credit rating, loan underwriting, solicitation of money (political, charitable or other), direct-mail or commercial targeting (5 U.S.C. 13107).