FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number: 3235-0287
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
Soffer Gad
   2. Issuer Name and Ticker or Trading Symbol
Atara Biotherapeutics, Inc. [ATRA] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Operating Officer
(Last)
(First)
(Middle)
3260 BAYSHORE BOULEVARD		 3. Date of Earliest Transaction (Month/Day/Year)
10/21/2014
(Street)

BRISBANE, CA 94005		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted Stock Unit (1) 10/21/2014   A   153,846     (2)   (3) Common Stock 153,846 $ 0 153,846 D  
Restricted Stock Unit (1) 10/21/2014   A   66,332     (4)   (5) Common Stock 66,332 $ 0 66,332 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Soffer Gad
3260 BAYSHORE BOULEVARD
BRISBANE, CA 94005		       Chief Operating Officer  

Signatures

 /s/ Tina Gullotta, Attorney-in-Fact for Gad Soffer   10/23/2014
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock or a cash settlement.
(2) The restricted stock units ("RSUs") were granted with both (a) a liquidity event-based vesting condition and (b) a service-based vesting condition, both of which conditions must be satisfied in order for the RSUs to vest. The liquidity event-based condition was satisfied upon the closing of the Issuer's initial public offering (the "IPO"). The shares that vest on the closing date of the IPO shall be settled on the first business day after the date that is six months after the closing of the IPO. For RSUs that vest after the closing of the IPO, the settlement shall occur on the first business day in January of the year immediately following the year in which the RSUs became vested. The RSUs vest as follows: 25% of the total number of shares on March 25, 2014 and 1/48th of the total number of shares monthly thereafter.
(3) The earlier of (i) March 13, 2020 or (ii) the second anniversary of termination date.
(4) The RSUs were granted with both (a) a liquidity event-based vesting condition and (b) a service-based vesting condition, both of which conditions must be satisfied in order for the RSUs to vest. The liquidity event-based condition was satisfied upon the closing of the Issuer's IPO. The shares that vest on the closing date of the IPO shall be settled on the first business day after the date that is six months after the closing of the IPO. For RSUs that vest after the closing of the IPO, the settlement shall occur on the first business day in January of the year immediately following the year in which the RSUs became vested. The RSUs vest as follows: 1/48th of the total number of shares monthly from January 10, 2014.
(5) The earlier of (i) January 10, 2021 or (ii) the second anniversary of termination date.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.