Ownership Submission
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, 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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(Print or Type Responses)
1. Name and Address of Reporting Person *
Parlati Francesco
   2. Issuer Name and Ticker or Trading Symbol
Calithera Biosciences, Inc. [CALA] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
VP, RESEARCH
(Last)
(First)
(Middle)
C/O CALITHERA BIOSCIENCES, INC., 343 OYSTER POINT BLVD. #200		 3. Date of Earliest Transaction (Month/Day/Year)
02/20/2018
(Street)

SOUTH SAN FRANCISCO, CA 94080		 4. If Amendment, Date Original Filed(Month/Day/Year)
02/22/2018		 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
Common Stock 02/20/2018   M   1,979 A $ 0.96 25,339 (1) (2) D  
Common Stock 02/20/2018   M   3,116 A $ 0.96 28,455 (1) (2) D  

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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
Employee Stock Option (Right to Buy) $ 0.96 02/20/2018   M     1,979   (3) 05/22/2023 Common Stock 1,979 $ 0 0 D  
Employee Stock Option (Right to Buy) $ 0.96 02/20/2018   M     3,116   (4) 05/22/2023 Common Stock 3,116 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Parlati Francesco
C/O CALITHERA BIOSCIENCES, INC.
343 OYSTER POINT BLVD. #200
SOUTH SAN FRANCISCO, CA 94080		       VP, RESEARCH  

Signatures

 /s/ Francesco Parlati   03/06/2018
**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) 7,967 shares were omitted from the Reporting Person's original Form 4, and also were omitted from the Reporting Person's Form 3 filed by the Reporting Person prior to the date the original Form 4 was filed.
(2) Includes 973 and 2,038 shares acquired under the Company's 2014 Employee Stock Purchase Plan on June 9, 2017 and December 8, 2017, respectively.
(3) 1/48th of the Option vests in equal monthly installments beginning November 15, 2012. The Option shall be subject to accelerated vesting as set fourth in the optionee's employment agreement with the Company.
(4) 1/48th of the Option vests in equal monthly installments one month after May 23, 2013. The Option shall be subject to accelerated vesting as set fourth in the optionee's employment agreement with the Company.

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