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 *
Landau Jeffrey B
  2. Issuer Name and Ticker or Trading Symbol
CytomX Therapeutics, Inc. [CTMX] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Business Officer
(Last)
(First)
(Middle)
C/O CYTOMX THERAPEUTICS, INC., 151 OYSTER POINT BLVD., SUITE 400		 3. Date of Earliest Transaction (Month/Day/Year)
01/18/2024
(Street)

SOUTH SAN FRANCISCO, CA 94080		 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 01/18/2024   A   30,000 (1) A $ 0 116,622 (2) D  
Common Stock               4,500 I Fidelity Traditional IRA
Common Stock               3,180 I Schwab ROTH IRA

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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
Stock Option (Right to Buy) $ 1.68 01/18/2024   A   140,000     (3) 01/17/2034 Common Stock 140,000 $ 0 140,000 D  
Performance Stock Units (PSUs) (4) 01/18/2024   A   75,000     (4)   (4) Common Stock 75,000 $ 0 75,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Landau Jeffrey B
C/O CYTOMX THERAPEUTICS, INC.
151 OYSTER POINT BLVD., SUITE 400
SOUTH SAN FRANCISCO, CA 94080		       Chief Business Officer  

Signatures

 /s/ Lloyd Rowland, as Attorney-in-Fact for Jeffrey B Landau   01/19/2024
**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) Constitute restricted stock units ("RSUs") for which the Reporting Person is entitled to receive one (1) share of Common Stock for each RSU upon vesting. 1/3rd of the RSUs vest annually on March 15 of each year, with the first 1/3rd vesting on March 15, 2025, subject to the Reporting Person continuing as a service provider through each such date.
(2) Includes 82,205 RSUs.
(3) 1/48th of the shares subject to the option vest on each monthly anniversary measured from January 18, 2024 (the "Vesting Commencement Date"), such that 100% of the shares subject to the option will be fully vested and exercisable on the fourth anniversary of the Vesting Commencement Date, subject to the Reporting Person's continued service to the Issuer through each such date.
(4) Each Performance-Based Restricted Stock Unit ("PSU") represents a contingent right to receive one (1) share of Common Stock upon vesting. 1/2 of the PSUs vest upon the achievement of each of two clinical milestones, subject to the Reporting Person continuing as a service provider through each such date.

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