Atara Biotherapeutics, Inc. (ATRA) ownership: Top institutional holder: BlackRock Fund Advisors ($15.78M). Insider activity: Net Seller (1 buys, 19 sells). SEC EDGAR first-party data.
| Holder | Shares | Market Value | Reported |
|---|---|---|---|
| BlackRock Fund Advisors | 1111507.00 | $15.78M | 2016-12-31 |
| VANGUARD GROUP INC | 225940.00 | $4.09M | 2025-12-31 |
| ADAGE CAPITAL PARTNERS GP, L.L.C. | 700000.00 | $3.31M | 2026-03-31 |
| MARSHALL WACE, LLP | 148632.00 | $2.69M | 2025-12-31 |
| Redmile Group, LLC | 441701.00 | $2.09M | 2026-03-31 |
| MACKENZIE FINANCIAL CORP | 313620.00 | $1.48M | 2026-03-31 |
| GLOBEFLEX CAPITAL L P | 77224.00 | $1.40M | 2025-12-31 |
| VANGUARD CAPITAL MANAGEMENT LLC | 217862.00 | $1.03M | 2026-03-31 |
| Insider | Transaction | Value | Date |
|---|---|---|---|
| Sell | null | 2026-06-09 | |
| Sell | null | 2026-06-09 | |
| Sell | null | 2026-06-09 | |
| Sell | null | 2026-05-18 | |
| Sell | null | 2026-05-18 | |
| Sell | null | 2026-05-18 | |
| Sell | null | 2026-05-18 | |
| Sell | null | 2026-05-07 |
Back to ATRA overview · ATRA earnings · All congressional trades
Institutional data from SEC Form 13F. Insider data from SEC Form 4. Congressional data from STOCK Act disclosures. Not personalized investment advice.