Who owns Atara Biotherapeutics, Inc.?
Prices and market caps: Cboe delayed data, at least 15 minutes delayed. Not real-time. Fundamentals from company filings.
Institutional ownership of ATRA from SEC Form 13F filings across 35 reporting managers. All positions are from one synchronized reporting period — 2026-06-30 books, filed up to 45 days after quarter end — so every row is comparable.
As of the 2026-06-30 reporting period, 35 institutions disclosed 4.5M shares of Atara Biotherapeutics, Inc. worth $50.8M — about 29.7% of shares outstanding; the largest disclosed holder is EcoR1 Capital, LLC. Source: SEC Form 13F filings, parsed by EvidInvest.
35
13F holders
$50.8M
value, 2026 filers
29.7%
of shares outstanding (4.5M sh)
5
new positions (2026 filers)
Top institutional holders
ordered by shares owned · positions as of 2026-06-30 · % of fund = share of the manager's own book · % of co. = share of ATRA's shares outstanding
| # | Manager | Shares | Value | % of fund | % of co. | Δ shares QoQ |
|---|---|---|---|---|---|---|
| 1 | EcoR1 Capital, LLC | 1.6M | $17.8M | 0.9% | 10.3% | +1458.3% |
| 2 | ADAGE CAPITAL PARTNERS GP, L.L.C. | 850,000 | $9.8M | 0.0% | 5.7% | +21.4% |
| 3 | Point72 Asset Management, L.P. | 687,718 | $7.9M | 0.0% | 4.6% | +254.0% |
| 4 | Redmile Group, LLC | 441,701 | $5.1M | 0.3% | 2.9% | 0.0% |
| 5 | VANGUARD CAPITAL MANAGEMENT LLC | 247,047 | $2.8M | 0.0% | 1.6% | +13.4% |
| 6 | MACKENZIE FINANCIAL CORP | 233,249 | $2.7M | 0.0% | 1.6% | -25.6% |
| 7 | BlackRock, Inc. | 84,455 | $969,544 | 0.0% | 0.6% | +6.9% |
| 8 | GEODE CAPITAL MANAGEMENT, LLC | 75,128 | $862,924 | 0.0% | 0.5% | +13.6% |
| 9 | STALEY CAPITAL ADVISERS INC | 50,000 | $574,000 | 0.0% | 0.3% | 0.0% |
| 10 | VANGUARD FIDUCIARY TRUST CO | 43,036 | $494,053 | 0.0% | 0.3% | +28.0% |
| 11 | ACADIAN ASSET MANAGEMENT LLC | 38,845 | $444 | 0.0% | 0.3% | -70.3% |
| 12 | JANE STREET GROUP, LLC | 30,345 | $348,360 | 0.0% | 0.2% | -10.4% |
| 13 | STATE STREET CORP | 26,453 | $303,680 | 0.0% | 0.2% | 0.0% |
| 14 | NORTHERN TRUST CORP | 16,591 | $190,465 | 0.0% | 0.1% | +34.4% |
| 15 | FMR LLC | 16,238 | $186,412 | 0.0% | 0.1% | 0.0% |
| 16 | XTX Topco LtdNEW | 15,303 | $175,678 | 0.0% | 0.1% | new |
| 17 | BRIDGEWAY CAPITAL MANAGEMENT, LLC | 14,000 | $160,720 | 0.0% | 0.1% | -57.2% |
| 18 | MILLENNIUM MANAGEMENT LLC | 12,680 | $145,566 | 0.0% | 0.1% | -73.4% |
| 19 | CITADEL ADVISORS LLCNEW | 10,159 | $116,625 | 0.0% | 0.1% | new |
| 20 | MORGAN STANLEY | 9,178 | $105,368 | 0.0% | 0.1% | +0.1% |
| 21 | ROYAL BANK OF CANADA | 4,743 | $55,000 | 0.0% | 0% | +9.8% |
| 22 | UBS Group AG | 3,979 | $45,679 | 0.0% | 0% | -92.1% |
| 23 | Vanguard Global Advisers, LLC | 1,456 | $16,715 | 0.0% | 0% | 0.0% |
| 24 | SBI Securities Co., Ltd. | 1,404 | $16,118 | 0.0% | 0% | -10.8% |
| 25 | JONES FINANCIAL COMPANIES LLLP | 803 | $8,440 | 0.0% | 0% | +14.2% |
Source: SEC Form 13F-HR filings (institutional managers over $100M in US-listed positions). 13Fs disclose long positions only, up to 45 days after quarter end; each manager's latest filed quarter is shown per row and dollar values are the manager's filed marks. Aggregates labeled "2026 filers" count only managers whose latest book is a 2026 quarter. Related: valuation · options positioning · supply chain. Research, not investment advice.