Atara Biotherapeutics
ATRA
37 hedge funds and large institutions have $12.4M invested in Atara Biotherapeutics in 2025 Q1 according to their latest regulatory filings, with 5 funds opening new positions, 8 increasing their positions, 13 reducing their positions, and 11 closing their positions.
5.51% less ownership
Funds ownership: 41.12% → 35.61% (-5.5%)
14% less funds holding
Funds holding: 43 → 37 (-6)
38% less repeat investments, than reductions
Existing positions increased: 8 | Existing positions reduced: 13
55% less first-time investments, than exits
New positions opened: 5 | Existing positions closed: 11
61% less capital invested
Capital invested by funds: $31.5M → $12.4M (-$19.1M)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
EC
EcoR1 Capital
San Francisco,
California
|
+$358K |
| 2 |
Susquehanna International Group
Bala Cynwyd,
Pennsylvania
|
+$358K |
| 3 |
SCA
STALEY CAPITAL ADVISERS
Pittsburgh,
Pennsylvania
|
+$262K |
| 4 |
UBS Group
Zurich,
Switzerland
|
+$205K |
| 5 |
GCP
GSA Capital Partners
London,
United Kingdom
|
+$169K |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Citadel Advisors
Miami,
Florida
|
-$3.56M |
| 2 |
Renaissance Technologies
New York
|
-$434K |
| 3 |
Marshall Wace
London,
United Kingdom
|
-$332K |
| 4 |
VPC
Vestal Point Capital
New York
|
-$270K |
| 5 |
CSS
Cubist Systematic Strategies
Stamford,
Connecticut
|
-$169K |
ATRA Hedge Fund Activity: Q1 2025 in Review
37 of the 7,471 institutional investors tracked by Wall St. Rank reported a position in Atara Biotherapeutics (ATRA) for Q1 2025, worth a combined $12.4M — down 61% from $31.5M a quarter earlier.
Sellers outnumbered buyers: 11 funds closed out of ATRA and 5 opened new positions — a net loss of 6 holders — while 13 trimmed existing stakes and 8 added.
The largest buyer was EcoR1 Capital, adding an estimated $358K. The largest seller was Citadel Advisors, exiting entirely with an estimated $3.56M sold.
- 37 institutional investors held Atara Biotherapeutics (ATRA) as of Q1 2025, down from 43 in Q4 2024.
- Funds reported $12.4M of Atara Biotherapeutics stock for Q1 2025, down 61% quarter-over-quarter.
- 5 funds opened new Atara Biotherapeutics positions in Q1 2025 and 11 closed out, a net change of -6 holders.
- The largest Atara Biotherapeutics buyer in Q1 2025 was EcoR1 Capital, an estimated $358K added.
- The largest Atara Biotherapeutics seller in Q1 2025 was Citadel Advisors, an estimated $3.56M sold.
Based on aggregated 13F filings for Q1 2025.