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 *
Watt Christopher
   2. Issuer Name and Ticker or Trading Symbol
TETRAPHASE PHARMACEUTICALS INC [TTPH] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP, Finance
(Last)
(First)
(Middle)
C/O TETRAPHASE PHARMACEUTICALS, INC., 480 ARSENAL STREET, SUITE 110		 3. Date of Earliest Transaction (Month/Day/Year)
01/17/2019
(Street)

WATERTOWN, MA 02472		 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
Common Stock 01/06/2019   A V 2,668 A (1) 21,782 D  
Common Stock 05/14/2018   A V 2,058 A (2) 23,840 D  
Common Stock 11/14/2018   A V 3,332 A (3) 27,172 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
Restricted Stock Units (4) 01/17/2019   A   80,000     (5)   (5) Common Stock 80,000 $ 0 80,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Watt Christopher
C/O TETRAPHASE PHARMACEUTICALS, INC.
480 ARSENAL STREET, SUITE 110
WATERTOWN, MA 02472		       SVP, Finance  

Signatures

 /s/Maria Stahl as Attorney-in-Fact for Christopher Watt   01/18/2019
**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) On January 6, 2016, the Reporting person was granted 12,500 restricted stock units ("RSUs")( the "2016 RSU grant") that were previously reported on Table II Of Form 4, which form was filed with the Securities and Exchange Commission on March 20, 2018. Of the 2016 RSU grant, 4,166 shares vested on January 6, 2019 of which 1,498 shares were withheld by the Issuer to satisfy the reporting person's tax withholding obligations in connection with the delivery of the conversion of the RSUs into common stock on the vesting date. The total number of shares beneficially owned by the reporting person includes the 2,668 RSUs converted into shares of common stock of the Issuer on the January 2019 vesting date. The RSUs converted into shares of common stock of the Issuer prior to the January 2019 vesting date were previously reported as shares beneficially owned by the reporting person.
(2) The amount of securities beneficially owned by the reporting person following the transaction reported on this Form 4 reflects the purchase by the reporting person of 2,058 shares of common stock on May 14, 2018 pursuant to the issuer's 2014 Employee Stock Purchase Plan.
(3) The amount of securities beneficially owned by the reporting person following the transaction reported on this Form 4 reflects the purchase by the reporting person of 3,332 shares of common stock on November 14, 2018 pursuant to the issuer's 2014 Employee Stock Purchase Plan.
(4) Each restricted stock unit represents a contingent right to receive one share of common stock of Tetraphase Pharmaceuticals, Inc. for no consideration.
(5) The restricted stock units vest in three equal installments on each of January 17, 2020, January 17, 2021 and January 17, 2022.

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