ATARA BIOTHERAPEUTICS INC (ATRA) Institutional Ownership and Insiders Activity
ATARA BIOTHERAPEUTICS INC (ATRA) is widely held by institutional investors, with 35 firms reporting positions valued at approximately $51.29M based on SEC Form 13F filings for the quarter ended June 30, 2026.
Ecor1 Capital, Llc is the largest disclosed holder, reporting approximately $17.82M in ATRA holdings in its latest filing.
Recent insider activity includes 4 tracked Form 4 transactions over the last three months, reflecting ongoing executive and director trading activity.
Institutional Holders
35
Total Reported Value
$51.29M
Largest Holder
Ecor1 Capital, Llc
Largest Position
$17.82M
Insider Transactions (90d)
4
Latest Filing Quarter
Q2 2026
New Institutional Positions
5
Funds Exiting Positions
2
Top Institutional Owners
View allInvestorReported Balance
Related ATRA Institutional Insights:
- ATRA 13F Institutional Holders
- ATRA Top Institutional Shareholders
- ATRA Institutional Ownership Changes
- Healthcare Sector Institutional Ownership
- Healthcare Sector Portfolio Overlap
- Institutional Portfolio Overlap & Shared Holdings
- Most Bought Healthcare Stocks By Institutional Investors
- Most Sold Healthcare Stocks By Institutional Investors
- ATRA Insider Trading & SEC Form 4 Activity
- ATRA Articles
- Top Institutional Investor Stock Rankings