Atara Biotherapeutics, Inc. - Common Stock, par value $0.0001 per share (ATRA)

CUSIP: 046513107

Q2 2024 13F Holders as of 30 Jun 2024

Holder snapshot 6 signals
Share change
-82,684,774
SEC-reported price per share
$8.50
Number of holders
5
Value change
-$88,647,049
Number of buys
1
Number of sells
77
Security identity Names, identifiers, and filing context for this profile. 1 source field
Shares outstanding
9,606,000

Security key

046513107

Report period

Q2 2024

Institutions

5

Top holders

5

Ownership snapshot

Top reported holders of ATRA - Atara Biotherapeutics, Inc. - Common Stock, par value $0.0001 per share (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.

Comparable stake leader
EcoR1 Capital, LLC
Disclosed value leader
EcoR1 Capital, LLC
Comparable rows
15/15
Latest evidence
31 Mar 2024
13F Lead comparable stake: 106% Showing 1-6 of 15 holder rows.

Quick read

EcoR1 Capital, LLC leads the comparable SEC ownership view at 106%.

15 of 15 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.

Open SEC evidence Opens EcoR1 Capital, LLC's linked filing trail.
Comparable ownership Top 5
EcoR1 Capital, LLC 106%
Redmile Group, LLC 96%
BlackRock Finance, Inc. 71%
BANK OF AMERICA CORP /DE/ 69%
CITADEL ADVISORS LLC 68%

Ownership % is shown only when SEC disclosures are safely comparable across share classes.

Detailed SEC evidence table Showing 1-6 of 15 holder rows
Holder Evidence Ownership % Position 12M Net Δ As of
EcoR1 Capital, LLC
13F
Company
13F
106%
$7,055,928
10,167,043 shares
31 Mar 2024
Redmile Group, LLC
13F
Company
13F
96%
$6,428,736
9,263,309 shares
31 Mar 2024
BlackRock Finance, Inc.
13F
Company
13F
71%
$4,741,047
6,831,479 shares
31 Mar 2024
BANK OF AMERICA CORP /DE/
13F
Company
13F
69%
$4,566,920
6,580,577 shares
31 Mar 2024
CITADEL ADVISORS LLC
13F
Company
13F
68%
$4,519,372
6,512,063 shares
31 Mar 2024
VANGUARD GROUP INC
13F
Company
13F
52%
$3,478,979
5,012,938 shares
31 Mar 2024
How to read this table

Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

13F holder rows

Institutional holders as of Q2 2024

Investor-level positions for this CUSIP, loaded as an interactive table.

Institutions
5
Shares
182,077
Rows available
5
Investor Option Weight % Change % SEC-reported value * Price Shares Share Change Activity Report Period

* SEC-reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that did not pass the local price check.

Compare Q2 2024 vs Q4 2025 Across Filers

Q4 2025 holders
0
Q2 2024 holders
5
Holder diff
5
Investor Q4 2025 Shares Q2 2024 Shares Share Diff Share Chg % Q4 2025 value Q2 2024 value Value change Value Chg %

Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).

Quarterly Holders Trend
Quarterly Value Trend
Quarterly Shares Trend
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