Atara Biotherapeutics, Inc. (ATRA) — Institutional Holders, Q2 2026
36 institutional investment managers reported a ATRA position on SEC Form 13F-HR for the quarter ended June 30, 2026, with a combined reported value of $51.3M. Every filer is listed below, ranked by position value. Put and call option positions are excluded, and a firm filing several lots or share classes is shown once with its total.
ATRA in Q2 2026: what funds did
Funds that filed a 13F for both Q1 2026 and Q2 2026, by what they did with the common stock. Share counts are adjusted for any split between the two quarters; dollar figures are the change in shares at this quarter’s price.
Biggest buyers
- EcoR1 CapitalAdded · +1,452,407 sh+$16.7M
- Point72 Asset Management, L.P.Added · +493,454 sh+$5.7M
- ADAGE CAPITAL PARTNERS GP, L.L.C.Added · +150,000 sh+$1.7M
- VANGUARD CAPITAL MANAGEMENTAdded · +29,185 sh+$335.0K
- XTX Topco LtdNew · +15,303 sh+$175.7K
Biggest sellers
- ACADIAN ASSET MANAGEMENTTrimmed · -92,065 sh-$1.1M
- MACKENZIE FINANCIALTrimmed · -80,371 sh-$922.7K
- UBS Group AGTrimmed · -46,091 sh-$529.1K
- MILLENNIUM MANAGEMENTTrimmed · -35,009 sh-$401.9K
- BRIDGEWAY CAPITAL MANAGEMENTTrimmed · -18,691 sh-$214.6K
ATRA 13F holders ranked 1–36 of 36
| # | Institution | Shares | Value | % of portfolio | QoQShares vs Q1 2026 |
|---|---|---|---|---|---|
| 1 | EcoR1 Capital#1 · 1,552,000 sh | 1,552,000 | $17.8M | 0.87% | +1458.3% |
| 2 | ADAGE CAPITAL PARTNERS GP, L.L.C.#2 · 850,000 sh | 850,000 | $9.8M | 0.01% | +21.4% |
| 3 | Point72 Asset Management, L.P.#3 · 687,718 sh | 687,718 | $7.9M | <0.01% | +254.0% |
| 4 | Redmile Group#4 · 441,701 sh | 441,701 | $5.1M | 0.34% | 0.0% |
| 5 | VANGUARD CAPITAL MANAGEMENT#5 · 247,047 sh | 247,047 | $2.8M | <0.01% | +13.4% |
| 6 | MACKENZIE FINANCIAL#6 · 233,249 sh | 233,249 | $2.7M | <0.01% | -25.6% |
| 7 | BlackRock#7 · 84,455 sh | 84,455 | $969.5K | 0.00% | +6.9% |
| 8 | GEODE CAPITAL MANAGEMENT#8 · 75,128 sh | 75,128 | $862.9K | 0.00% | +13.6% |
| 9 | STALEY CAPITAL ADVISERS#9 · 50,000 sh | 50,000 | $574.0K | 0.02% | 0.0% |
| 10 | VANGUARD FIDUCIARY#10 · 43,036 sh | 43,036 | $494.1K | <0.01% | +28.0% |
| 11 | ACADIAN ASSET MANAGEMENT#11 · 38,845 sh | 38,845 | $444.0K | <0.01% | -70.3% |
| 12 | JANE STREET GROUP#12 · 30,345 sh | 30,345 | $348.4K | 0.00% | -10.4% |
| 13 | STATE STREET#13 · 26,453 sh | 26,453 | $303.7K | 0.00% | 0.0% |
| 14 | NORTHERN#14 · 16,591 sh | 16,591 | $190.5K | 0.00% | +34.4% |
| 15 | FMR#15 · 16,238 sh | 16,238 | $186.4K | 0.00% | 0.0% |
| 16 | XTX Topco Ltd#16 · 15,303 sh | 15,303 | $175.7K | <0.01% | New |
| 17 | BRIDGEWAY CAPITAL MANAGEMENT#17 · 14,000 sh | 14,000 | $160.7K | <0.01% | -57.2% |
| 18 | MILLENNIUM MANAGEMENT#18 · 12,680 sh | 12,680 | $145.6K | <0.01% | -73.4% |
| 19 | CITADEL ADVISORS#19 · 10,159 sh | 10,159 | $116.6K | 0.00% | New |
| 20 | MORGAN STANLEY#20 · 9,178 sh | 9,178 | $105.4K | 0.00% | +0.1% |
| 21 | ROYAL BANK OF CANADA#21 · 4,743 sh | 4,743 | $55.0K | 0.00% | +9.8% |
| 22 | UBS Group AG#22 · 3,979 sh | 3,979 | $45.7K | 0.00% | -92.1% |
| 23 | Vanguard Global Advisers#23 · 1,456 sh | 1,456 | $16.7K | 0.00% | 0.0% |
| 24 | SBI Securities , Ltd.#24 · 1,404 sh | 1,404 | $16.1K | — | -10.8% |
| 25 | JONES FINANCIAL COMPANIES LLLP#25 · 803 sh | 803 | $8.4K | 0.00% | +14.2% |
| 26 | Caitong International Asset Management , Ltd#26 · 311 sh | 311 | $3.6K | <0.01% | New |
| 27 | BARCLAYS PLC#27 · 304 sh | 304 | $3.5K | 0.00% | New |
| 28 | Banque Transatlantique SA#28 · 176 sh | 176 | $3.1K | <0.01% | 0.0% |
| 29 | WELLS FARGO & COMPANY#29 · 251 sh | 251 | $2.9K | 0.00% | 0.0% |
| 30 | JPMORGAN CHASE#30 · 216 sh | 216 | $2.4K | 0.00% | 0.0% |
| 31 | CITIGROUP#31 · 97 sh | 97 | $1.1K | 0.00% | +9600.0% |
| 32 | BNP PARIBAS FINANCIAL MARKETS#32 · 46 sh | 46 | $528.00 | 0.00% | -20.7% |
| 33 | PlanVest Financial#33 · 28 sh | 28 | $321.00 | <0.01% | 0.0% |
| 34 | KERR FINANCIAL PLANNING#34 · 24 sh | 24 | $276.00 | <0.01% | 0.0% |
| 35 | OSAIC#35 · 10 sh | 10 | $114.00 | 0.00% | 0.0% |
| 36 | Rockefeller Capital Management L.P.#36 · 8 sh | 8 | $92.00 | 0.00% | 0.0% |
Funds that sold out of ATRA in Q2 2026 (2)
Held ATRA at the end of Q1 2026 and filed a Q2 2026 13F without it. Not in the list above, because they no longer hold it. Largest prior position first.
| Institution | Shares sold | Value in Q1 2026 |
|---|---|---|
| RHUMBLINE ADVISERS175 sh | 175 | $827.00 |
| Western Wealth Management1 sh | 1 | $5.00 |
Source: Form 13F-HR filings on SEC EDGAR, Q2 2026. Values are as reported by each manager at quarter end. “% of portfolio” is the position’s share of the manager’s total reported 13F value for the same quarter. “New” means the manager filed a 13F for Q1 2026 without this position; a dash means no comparison is available. Where a manager’s own filing is internally inconsistent its value is withheld and it is listed last. 13F data shows reported holdings, not recommendations.