Form 8-K

8-K — Atara Biotherapeutics, Inc.

Accession: 0001213900-26-068264

Filed: 2026-06-12

Period: 2026-06-09

CIK: 0001604464

SIC: 2836 (BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES))

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Submission of Matters to a Vote of Security Holders

Documents

8-K — ea0294561-8k_atara.htm (Primary)

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8-K — CURRENT REPORT

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UNITED

STATES

SECURITIES

AND EXCHANGE COMMISSION

WASHINGTON,

D.C. 20549

FORM

8-K

CURRENT

REPORT

Pursuant

to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date

of Report (Date of earliest event reported): June 9, 2026

Atara

Biotherapeutics, Inc.

(Exact

name of Registrant as Specified in Its Charter)

Delaware

001-36548

46-0920988

(State

or Other Jurisdiction

of Incorporation)

(Commission

File Number)

(IRS

Employer

Identification No.)

1280

Rancho Conejo Blvd

Thousand Oaks, California

91320

(Address

of Principal Executive Offices)

(Zip Code)

Registrant’s

Telephone Number, Including Area Code: (805) 632-4211

Not

Applicable

(Former

Name or Former Address, if Changed Since Last Report)

Check

the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under

any of the following provisions (see General Instruction A.2. below):

☐ Written

communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting

material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement

communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement

communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities

pursuant to Section 12 (b) of the Act:

Title of Each Class

Trading Symbol(s)

Name of Each Exchange on Which

Registered

Common

Stock, par value $0.0001 per share

ATRA

The

Nasdaq Stock Market LLC

Indicate

by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405

of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging

growth company ☐

an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying

with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item

5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of

Certain Officers.

June 11, 2026, the Board of Directors (the “Board”) of Atara Biotherapeutics, Inc. (the

“Company”) appointed Brian Cherry to serve as a member of the Board as a Class I director, effective June

11, 2026 (the “Effective Date”). Mr. Cherry was also appointed to the Audit Committee of the

Board.

The

Board has determined that Mr. Cherry is independent under the Company’s Corporate Governance Guidelines, applicable U.S. Securities

Exchange Commission (“SEC”) requirements and Nasdaq listing standards. There are no arrangements

or understandings between Mr. Cherry and any other persons pursuant to which he was elected as a director of the Company. There

are no family relationships between Mr. Cherry and any director or executive officer of the Company, and he has no direct or indirect

material interest in any transaction required to be disclosed pursuant to Item 404(a) of Regulation S-K.

In connection with his appointment, on the Effective Date, the Board approved

an initial equity award to Mr. Cherry of 24,000 restricted stock units covering shares of the Company’s Common Stock, which will

vest on an annual basis over three years, subject to his continuous service as a member of the Board. Mr. Cherry will otherwise participate

in the Company’s non-employee director compensation arrangements, which are generally described under the heading “2025 Non-Employee

Director Compensation” in the Company’s Proxy Statement for its 2026 Annual Meeting of Stockholders as filed with the SEC

on April 24, 2026 (the “Proxy Statement”), including an annual cash retainer of $55,000 starting on the Effective Date, with

payment pro-rated for any partial period of service. The Company also entered into its standard form of indemnification agreement with

Mr. Cherry.

Item

5.07 Submission of Matters to a Vote of Security Holders.

June 9, 2026, the Company held its 2026 annual meeting of stockholders (the “Annual Meeting”). The following

is a brief description of each matter voted upon at the Annual Meeting, as well as the number of votes cast for or against each matter

and the number of abstentions and broker non-votes with respect to each matter. A more complete description of each matter is described

in more detail in the Proxy Statement.

1. Election

of Directors

Nominee

For

Withheld

Broker

Non-Votes

AnhCo

Nguyen Ph.D.

3,543,113

32,311

2,945,628

Nachi

Subramanian

2,581,435

993,989

2,945,628

Each

of the two nominees for director was elected to serve until the 2029 annual meeting of stockholders and until their respective successors

are elected.

2. Advisory

vote to approve on the compensation of the Company’s named executive officers

For

Against

Abstain

Broker

Non-Votes

3,526,411

44,481

4,532

2,945,628

The

stockholders approved, on an advisory basis, the compensation awarded to the Company’s named executive officers, as disclosed in

the Proxy Statement.

3. Proposal

to approve the first amendment to the Company’s 2024 Equity Incentive Plan to increase

the number of shares of common stock reserved for issuance thereunder by 400,000

For

Against

Abstain

Broker

Non-Votes

3,521,021

51,327

3,076

2,945,628

The

stockholders approved the amendment to the Company’s 2024 Equity Incentive Plan, as disclosed in the Proxy Statement.

4. Ratification

of appointment of independent registered public accounting firm

For

Against

Abstentions

6,490,311

29,237

1,504

The

stockholders ratified the appointment of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for

the fiscal year ending December 31, 2026.

SIGNATURES

Pursuant

to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by

the undersigned thereunto duly authorized.

Atara

Biotherapeutics, Inc.

By:

/s/

AnhCo Nguyen Ph.D.

AnhCo

Nguyen Ph.D.

President

and Chief Executive Officer

Date:

June 12, 2026

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