Sec Form 4 Filing - Porter Derrell @ Atara Biotherapeutics, Inc. - 2018-05-15

Insider filing report for Changes in Beneficial Ownership
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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
Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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1. Name and Address of Reporting Person
Porter Derrell
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)
SVP, Head of Global Commercial
(Last) (First) (Middle)
C/O ATARA BIOTHERAPEUTICS, INC., 611 GATEWAY BOULEVARD, SUITE 900
3. Date of Earliest Transaction (MM/DD/YY)
05/15/2018
(Street)
SOUTH SAN FRANCISCO, CA94080
4. If Amendment, Date Original Filed (MM/DD/YY)
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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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
Common Stock 05/15/2018 M( 1 ) 16,334 A $ 14.3 28,834 D
Common Stock 05/15/2018 S( 1 ) 16,334 D $ 45.02 ( 2 ) 12,500 D
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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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
(MM/DD/YY)
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
Employee Stock Option (Right to Buy) $ 14.3 05/15/2018 M( 1 ) 16,334 ( 3 ) 05/10/2024 Common Stock 16,334 $ 0 113,666 D
Reporting Owners
Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Porter Derrell
C/O ATARA BIOTHERAPEUTICS, INC.
611 GATEWAY BOULEVARD, SUITE 900
SOUTH SAN FRANCISCO, CA94080
SVP, Head of Global Commercial
Signatures
/s/ David Tucker, Attorney-in-Fact for Derrell Porter 05/16/2018
Signature of Reporting Person Date
Explanation of Responses:
( 1 )Transaction pursuant to Rule 10b5-1 Plan adopted March 9, 2018.
( 2 )The price in Column 4 is a weighted average sale price. The prices actually received ranged from $45.00 to $45.05. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range
( 3 )25% of the shares subject to the option vest and become exercisable on May 10, 2018 and 1/48th of the shares subject to the stock option vest and become exercisable each full month thereafter.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).

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