Security key
046513206
Atara Biotherapeutics, Inc. - Common Stock, par value $0.0001 per share (ATRA)
CUSIP: 046513206
Q1 2025 13F Holders as of 31 Mar 2025
- Security type / class
- Equity / Common Stock, par value $0.0001 per share
- Total 13F shares
- 2,086,793
- Total 13F value
- $12,393,904
- Share change
- -281,482
- SEC-reported price per share
- $5.94
- Number of holders
- 36
- Value change
- -$4,023,428
- Number of buys
- 12
- Number of sells
- 21
- Shares outstanding
- 9,606,000
Holder snapshot
6 signals
Security identity
Names, identifiers, and filing context for this profile.
1 source field
Report period
Q1 2025
Institutions
36
Top holders
10
ATRA full security history
Ownership snapshot
Full 13F holder table
Newer quarter: Q2 2026
Atara Biotherapeutics, Inc. SEC filings
Atara Biotherapeutics, Inc. company facts
Broader feeds
Reporting periods
Holder history for CUSIP 046513206
Recent filing periods:
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 Dec 2024
13F
Lead comparable stake: 5.5%
Showing 1-6 of 15 holder rows.
Quick read
EcoR1 Capital, LLC leads the comparable SEC ownership view at 5.5%.
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
5.5%
Redmile Group, LLC
4.6%
CITADEL ADVISORS LLC
2.8%
BANK OF AMERICA CORP /DE/
2.1%
VANGUARD GROUP INC
1.9%
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
|
5.5%
|
$7,082,704
532,134 shares
|
— | 31 Dec 2024 |
| Redmile Group, LLC |
13F
Company
|
4.6%
|
$5,879,040
441,701 shares
|
— | 31 Dec 2024 |
| CITADEL ADVISORS LLC |
13F
Company
|
2.8%
|
$3,558,469
267,353 shares
|
— | 31 Dec 2024 |
| BANK OF AMERICA CORP /DE/ |
13F
Company
|
2.1%
|
$2,730,813
205,170 shares
|
— | 31 Dec 2024 |
| VANGUARD GROUP INC |
13F
Company
|
1.9%
|
$2,379,588
178,782 shares
|
— | 31 Dec 2024 |
| Vestal Point Capital, LP |
13F
Company
|
1.3%
|
$1,663,750
125,000 shares
|
— | 31 Dec 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 Q1 2025
Investor-level positions for this CUSIP, loaded as an interactive table.
Institutions
36
Shares
2,086,793
Rows available
36
| 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 Q1 2025 vs Q1 2025 Across Filers
Q1 2025 holders
36
Q1 2025 holders
36
Holder diff
0
| Investor | Q1 2025 Shares | Q1 2025 Shares | Share Diff | Share Chg % | Q1 2025 value | Q1 2025 value | Value change | Value Chg % |
|---|
Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).
Quarterly Holders Trend
Quarterly Value Trend
Quarterly Shares Trend