Sean A. McCarthy - 17 Dec 2023 Form 4 Insider Report for CytomX Therapeutics, Inc. (CTMX)

Role: CEO, Director
Signature: /s/ Lloyd Rowland, as Attorney-in-Fact for Sean A. McCarthy
Issuer symbol: CTMX
Transactions as of: 17 Dec 2023
Net transactions value: $0
Form type: 4
Filing time: 19 Dec 2023, 19:57:37 UTC
Previous filing: 22 Sep 2023
Next filing: 22 Dec 2023
SEC: View on sec.gov

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	CTMX	Common Stock	Options Exercise	$0	+37,500	+8.7%	$0.000000	468,255	17 Dec 2023	Direct	F1, F2
holding	CTMX	Common Stock						93,158	17 Dec 2023	See footnote	F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	CTMX	Performance Stock Units (PSUs)	Options Exercise	$0	-37,500	-50%	$0.000000	37,500	17 Dec 2023	Common Stock	37,500		Direct	F1, F4

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Represents partial vesting of a Performance Stock Unit ("PSU") award initially granted on August 10, 2022.
F2	Includes 161,250 restricted stock units.
F3	Shares held by Sean A. McCarthy 2018 Trust, of which Reporting Person is trustee.
F4	Each PSU represents a contingent right to receive one share of the Issuer's Common Stock upon vesting. In connection with the vesting reported herein, 50% of the PSUs vested upon achievement of a certain performance-based milestone. The remaining 50% of the PSUs vest upon achievement of a certain performance-based milestone by 12/31/2024.