EcoR1 Capital, LLC - 30 Sep 2025 SCHEDULE 13G/A Report for Atara Biotherapeutics, Inc. Common Stock (ATRA)

Filing Manager
EcoR1 Capital, LLC
Reporting Manager
EcoR1 Capital, LLC
Security
Atara Biotherapeutics, Inc. Common Stock
Symbol
ATRA
Shares outstanding
7,230,838 shares
Disclosed Ownership
715,853 shares
Ownership
9.9%
Form type
SCHEDULE 13G/A
Filing time
14 Nov 2025, 16:05:29 UTC
Date of event
30 Sep 2025
SEC
View on sec.gov

Reporting Managers (3)

Name Ownership Shares Owned sole voting power shared voting power Signature Title CIK
EcoR1 Capital, LLC 9.9% 715,853 0 715,853 /s/ Oleg Nodelman Manager
Oleg Nodelman 9.9% 715,853 0 715,853 /s/ Oleg Nodelman Reporting person
EcoR1 Capital Fund Qualified, L.P. 9.3% 667,639 0 667,639 /s/ Oleg Nodelman Manager of the General Partner, EcoR1 Capital, LLC