Form
SCHEDULE 13D/A
Active or control-oriented beneficial ownership filing.
Redmile Group, LLC - 12 Nov 2025 SCHEDULE 13D/A Report for Atara Biotherapeutics, Inc. Common Stock, par value $0.0001 per share (ATRA)
- Filing manager
- Redmile Group, LLC
- Reporting owner
- Redmile Group, LLC
- Beneficially owned shares
- 751,223 shares
- Large-stake signal
-
Ownership
9.9%Beneficial ownership of this reported class.
Shares
751,223 sharesShares beneficially owned as disclosed.
Event date
12 Nov 2025Date tied to the ownership event or amendment.
Accepted by SEC
14 Nov 2025EDGAR acceptance date.
How to read this large-stake filing
- Schedule 13D/G filings focus on beneficial ownership stakes, not a full portfolio.
- Compare this filing with the holder history and issuer page before treating the percentage as a current position.
- Use amendments to understand whether the disclosed stake increased, decreased, or changed reporting status.
- Class ownership
- 9.9%
- Symbol
- ATRA
- Shares outstanding
- 7,588,111 shares
- SEC form
- SCHEDULE 13D/A
- Accepted by SEC
- 14 Nov 2025, 16:19:25 UTC
- Event date
- 12 Nov 2025
- Prior SEC filing
- 23 May 2025
- Source filing
- View source filing
Ownership signal
CIK-linked ownership evidence from parsed SEC filings.
2 signals
Subject security
Names, identifiers, and filing context for this profile.
2 source fields
Source evidence
Original filing metadata and source links for verification.
5 source fields
Key filing fact
Redmile Group, LLC disclosed 9.9% ownership in Atara Biotherapeutics, Inc. Common Stock, par value $0.0001 per share (ATRA) on 12 Nov 2025.
Key facts
- Redmile Group, LLC filed SCHEDULE 13D/A for Atara Biotherapeutics, Inc. Common Stock, par value $0.0001 per share (ATRA).
- Disclosed ownership: 9.9%.
- Date of event: 12 Nov 2025.
Change
- Previous schedule filing date: 23 May 2025.
- Current filing was accepted on 14 Nov 2025, 16:19.
Research use
- This page turns one Schedule 13D/G filing into a quick large-stake read before the raw reporting-person rows.
- Use the linked SEC filing as the source of truth for ownership percentages, shares, and reporting-party details.
Evidence
Backed by Schedule 13D/13G
View source filing
Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.
Reporting persons
Disclosed reporting parties (5)
Names, ownership percentages, voting power, signatures, titles, and CIKs as disclosed in this Schedule 13D/G filing.
| Name | Ownership | Shares owned | Sole voting power | Shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| Redmile Group, LLC | 9.9% | 751,223 | 0 | 751,223 | /s/ Jeremy C. Green | Managing Member | 0001425738 |
| Jeremy C. Green | 9.9% | 751,223 | 0 | 751,223 | /s/ Jeremy C. Green | Jeremy C. Green | 0001650527 |
| RedCo I, L.P. | 4.7% | 347,442 | 0 | 347,442 | /s/ Jeremy C. Green | Managing Member of RedCo I (GP), LLC, general partner of RedCo I, L.P. | 0001813157 |
| Redmile Biopharma Investments II, L.P. | 6% | 452,153 | 0 | 452,153 | /s/ Jeremy C. Green | Managing Member of Redmile Biopharma Investments II (GP), LLC, general partner of Redmile Biopharma Investments II, L.P. | 0001772230 |
| Redmile Strategic Long Only Trading Sub, Ltd. | 5% | 376,377 | 0 | 376,377 | /s/ Jeremy C. Green | Managing Member of Redmile Group, LLC, investment manager of Redmile Strategic Long Only Trading Sub, Ltd. | 0002048243 |
CIK / CUSIP context first