|
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549 |
SCHEDULE 13D
Under the Securities Exchange Act of 1934
(Amendment No. 3)*
|
Atara Biotherapeutics, Inc. (Name of Issuer) |
Common Stock, par value $0.0001 per share (Title of Class of Securities) |
(CUSIP Number) |
Redmile Group, LLC 900 Larkspur Landing Circle, Suite 270, Larkspur, CA, 94939 (415) 489-9980 (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) |
07/22/2026 (Date of Event Which Requires Filing of This Statement) |
SCHEDULE 13D
|
| CUSIP No. |
| 1 |
Name of reporting person
Redmile Group, LLC | ||||||||
| 2 | Check the appropriate box if a member of a Group (See Instructions)
(a)
(b) | ||||||||
| 3 | SEC use only | ||||||||
| 4 |
Source of funds (See Instructions)
OO | ||||||||
| 5 |
Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)
| ||||||||
| 6 | Citizenship or place of organization
DELAWARE
| ||||||||
| Number of Shares Beneficially Owned by Each Reporting Person With: |
| ||||||||
| 11 | Aggregate amount beneficially owned by each reporting person
950,994.00 | ||||||||
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)
| ||||||||
| 13 | Percent of class represented by amount in Row (11)
9.9 % | ||||||||
| 14 | Type of Reporting Person (See Instructions)
IA, OO |
SCHEDULE 13D
|
| CUSIP No. |
| 1 |
Name of reporting person
Green Jeremy | ||||||||
| 2 | Check the appropriate box if a member of a Group (See Instructions)
(a)
(b) | ||||||||
| 3 | SEC use only | ||||||||
| 4 |
Source of funds (See Instructions)
OO | ||||||||
| 5 |
Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)
| ||||||||
| 6 | Citizenship or place of organization
UNITED KINGDOM
| ||||||||
| Number of Shares Beneficially Owned by Each Reporting Person With: |
| ||||||||
| 11 | Aggregate amount beneficially owned by each reporting person
950,994.00 | ||||||||
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)
| ||||||||
| 13 | Percent of class represented by amount in Row (11)
9.9 % | ||||||||
| 14 | Type of Reporting Person (See Instructions)
IN, HC |
SCHEDULE 13D
|
| CUSIP No. |
| 1 |
Name of reporting person
Redmile Biopharma Investments II, L.P. | ||||||||
| 2 | Check the appropriate box if a member of a Group (See Instructions)
(a)
(b) | ||||||||
| 3 | SEC use only | ||||||||
| 4 |
Source of funds (See Instructions)
WC | ||||||||
| 5 |
Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)
| ||||||||
| 6 | Citizenship or place of organization
DELAWARE
| ||||||||
| Number of Shares Beneficially Owned by Each Reporting Person With: |
| ||||||||
| 11 | Aggregate amount beneficially owned by each reporting person
631,020.00 | ||||||||
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)
| ||||||||
| 13 | Percent of class represented by amount in Row (11)
6.6 % | ||||||||
| 14 | Type of Reporting Person (See Instructions)
PN |
SCHEDULE 13D
|
| CUSIP No. |
| 1 |
Name of reporting person
Redmile Strategic Long Only Trading Sub, Ltd. | ||||||||
| 2 | Check the appropriate box if a member of a Group (See Instructions)
(a)
(b) | ||||||||
| 3 | SEC use only | ||||||||
| 4 |
Source of funds (See Instructions)
WC | ||||||||
| 5 |
Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)
| ||||||||
| 6 | Citizenship or place of organization
CAYMAN ISLANDS
| ||||||||
| Number of Shares Beneficially Owned by Each Reporting Person With: |
| ||||||||
| 11 | Aggregate amount beneficially owned by each reporting person
401,901.00 | ||||||||
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)
| ||||||||
| 13 | Percent of class represented by amount in Row (11)
4.2 % | ||||||||
| 14 | Type of Reporting Person (See Instructions)
CO |
SCHEDULE 13D
|
| Item 1. | Security and Issuer |
| (a) | Title of Class of Securities:
Common Stock, par value $0.0001 per share |
| (b) | Name of Issuer:
Atara Biotherapeutics, Inc. |
| (c) | Address of Issuer's Principal Executive Offices:
1280 Rancho Conejo Blvd, Thousand Oaks,
CALIFORNIA
, 91320. |
| Item 2. | Identity and Background |
| (a) | This Amendment No. 3 to Schedule 13D (this "Amendment") amends and supplements the Schedule 13D filed with the SEC on May 23, 2025, which was previously amended and supplemented by that Amendment No. 1 to Schedule 13D filed with the SEC on November 14, 2025 and that Amendment No. 2 to Schedule 13D filed with the SEC on May 14, 2026 (collectively, the "Prior Schedule 13D").
This Amendment reports the exercise of certain pre-funded warrants to purchase Common Stock (the "Warrants") by Redmile Strategic Long Only Trading Sub, Ltd. ("Redmile Long Only") and Redmile Biopharma investments II, L.P. ("RBI II" and collectively with Redmile Long Only, Redmile Group, LLC and Jeremy Green, the "Reporting Persons") described in Item 5(a) below and the resulting change in the beneficial ownership of Redmile Long Only following such exercise.
Capitalized terms used but not defined in this Amendment shall have the meanings set forth in the Prior Schedule 13D. Except as specifically amended by this Amendment, the Prior Schedule 13D is unchanged. |
| Item 3. | Source and Amount of Funds or Other Consideration |
On July 16, 2026, Redmile Group, LLC ("Redmile") exercised certain Warrants held by RBI II and Redmile Long Only through a "cashless exercise" to acquire the Issuer's Common Stock. The transactions resulted in the Issuer (i) withholding 53 shares of Common Stock from RBI II and 7 shares of Common Stock from Redmile Long Only to pay the exercise price under the terms of the Warrants and (ii) issuing the remaining 174,247 shares of Common Stock to RBI II and 20,904 shares of Common Stock to Redmile Long Only. | |
| Item 5. | Interest in Securities of the Issuer |
| (a) | Item 5(a) of the Prior Schedule 13D is hereby amended and restated in its entirety as follows:
The aggregate amount of shares of Common Stock that may be deemed beneficially owned by the Reporting Persons is comprised of (i) 636,852 shares of Common Stock held by certain investment vehicles for which Redmile is the investment manager (the "Redmile Funds"), including the 316,878 shares of Common Stock directly held by RBI II and the 87,759 shares of Common Stock directly held by Redmile Long Only, and (ii) 314,142 shares of Common Stock issuable to the Redmile Funds, including RBI II and Redmile Long Only, upon exercise of certain Warrants, which is the maximum number of shares of Common Stock that could be issued upon exercise of the Warrants under the 9.99% beneficial ownership limitation (the "Beneficial Ownership Limitation"). The Redmile Funds hold Warrants that may be exercised into 3,217,632 shares of Common Stock issuable upon exercise of the Warrants, including the 1,879,855 shares of Common Stock issuable upon exercise of the remaining Warrants directly held by RBI II, and the 806,670 shares of Common Stock issuable upon exercise of the remaining Warrants directly held by Redmile Long Only, each of which is subject to the Beneficial Ownership Limitation. All of the reported securities are directly owned by certain Redmile Funds, including RBI II and Redmile Long Only. Redmile may be deemed to beneficially own these securities in its capacity as their investment manager with discretion to vote and dispose of the securities held by the Redmile Funds. Mr. Green also may be deemed to beneficially own these securities as the principal of Redmile. Redmile and Mr. Green each disclaim beneficial ownership of these securities, except to the extent of its or his pecuniary interest in such securities, if any.
Percentage based on the sum of: (i) 9,010,172 shares of Common Stock outstanding as of May 8, 2026, as reported by the Issuer in its Form 10-Q for the quarterly period ended March 31, 2026 filed with the Securities and Exchange Commission on May 12, 2026, plus (ii) 195,151 shares of Common Stock issued to RBI II and Redmile Long Only upon exercise of certain Warrants, plus (iii) 314,142 shares of Common Stock issuable upon exercise of certain Warrants directly held by the Redmile Funds, which due to the Beneficial Ownership Limitation is the maximum number of shares that could be issued upon exercise of those Warrants. |
| (b) | Item 5(b) of the Prior Schedule 13D is hereby amended and restated in its entirety as follows:
Redmile:
(1) Sole Voting Power: 0
(2) Shared Voting Power: 950,994
(3) Sole Dispositive Power: 0
(4) Shared Dispositive Power: 950,994
Jeremy C. Green:
(1) Sole Voting Power: 0
(2) Shared Voting Power: 950,994
(3) Sole Dispositive Power: 0
(4) Shared Dispositive Power: 950,994
RBI II:
(1) Sole Voting Power: 0
(2) Shared Voting Power: 631,020
(3) Sole Dispositive Power: 0
(4) Shared Dispositive Power: 631,020
Redmile Long Only:
(1) Sole Voting Power: 0
(2) Shared Voting Power: 401,901
(3) Sole Dispositive Power: 0
(4) Shared Dispositive Power: 401,901 |
| (c) | See the response to Item 3. Except as disclosed in Item 3, no reportable transactions were effected by any Reporting Persons during the past sixty days. |
| (e) | Redmile Long Only ceased to be a 5% beneficial owner on July 22, 2026 solely as a result of the exercise of the pre-funded warrants described in Item 3 above. |
| SIGNATURE | |
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
|
|
|
|
|
|
|
|
|