[Form 4] CytomX Therapeutics, Inc. Insider Trading Activity

Rhea-AI Filing Summary

CytomX Therapeutics (CTMX) Chief Financial Officer Christopher Ogden reported option and performance‑unit awards on Sept 26, 2025. He was granted a stock option to buy 78,250 shares at a $2.90 exercise price that vests monthly over four years beginning Sept 26, 2025, and 39,150 Performance Stock Units (PSUs) that vest in three tranches tied to clinical milestones, each PSU convertible into one share on vesting. Following these awards, Mr. Ogden beneficially owns 78,250 option shares and 39,150 PSUs, all held directly. The option expires Sept 25, 2035. The filing is signed Sept 30, 2025.

Positive

• Alignment of incentives: Option vests monthly over four years, supporting retention.
• Performance linkage: 39,150 PSUs vest upon clinical milestones, tying compensation to development outcomes.
• Transparent disclosure: Filing provides vesting schedules, exercise price ($2.90), expiry (09/25/2035), and quantities.

Negative

• Potential future dilution: Total of 117,400 equity interests could dilute existing shareholders if exercised or settled.
• Concentration in executive compensation: Large grant to a single officer may be material depending on company size (company size not provided in this filing).

Insights

Securities Analyst

TL;DR: Insider received standard grant-based compensation: an option and milestone-driven PSUs totaling 117,400 equity interests.

The grants indicate compensation tied to service and clinical progress rather than immediate stock transfers. The option vests monthly over four years, aligning retention incentives, while PSUs vest upon achievement of three clinical milestones, aligning pay with development objectives. The exercise price of $2.90 and ten-year term are typical for executive option awards. The direct ownership of these instruments means potential future dilution if and when exercised or settled.

Corporate Governance Expert

TL;DR: Grants reflect governance-standard practices linking pay to tenure and milestone achievements.

The structure—time‑based option vesting and milestone‑based PSUs—follows common governance practices to align executive incentives with long‑term company performance and clinical progress. The clear vesting schedules and direct ownership are disclosed appropriately. The filing contains required detail on vesting commencement, milestone structure, and security terms, enabling investors to assess potential dilution timing.

SEC Form 4

FORM 4

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
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

Ogden Christopher

(Last) (First) (Middle)

C/O CYTOMX THERAPEUTICS, INC.

151 OYSTER POINT BLVD., SUITE 400

(Street)

SOUTH SAN FRANCISCO CA 94080

(City) (State) (Zip)

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 Financial Officer

3. Date of Earliest Transaction (Month/Day/Year)
09/26/2025

4. If Amendment, Date of 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

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

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 Securities Underlying Derivative Security (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: 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)	$2.9	09/26/2025		A		78,250		(1)	09/25/2035	Common Stock	78,250	$0	78,250	D
Performance Stock Units (PSUs)	(2)	09/26/2025		A		39,150		(2)	(2)	Common Stock	39,150	$0	39,150	D

Explanation of Responses:

1. 1/48th of the shares subject to the option vest on each monthly anniversary measured from September 26, 2025 (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.

2. Each Performance Stock Unit ("PSU") represents a contingent right to receive one (1) share of Common Stock upon vesting. 1/3 of the PSUs vest upon the achievement of each of three clinical milestones, subject to the Reporting Person continuing as a service provider through each such date.

	/s/ Christopher Ogden	09/30/2025
	** Signature of Reporting Person	Date
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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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FAQ

What equity did CTMX CFO Christopher Ogden receive on 09/26/2025?

He received a stock option for 78,250 shares at a $2.90 exercise price and 39,150 Performance Stock Units (PSUs).

When do Mr. Ogden's option shares vest and expire?

The option vests 1/48th monthly beginning 09/26/2025 (fully vested after four years) and expires on 09/25/2035.

How do the PSUs awarded to the CTMX CFO vest?

Each PSU vests upon achievement of one of three clinical milestones (1/3 per milestone), contingent on continued service.

How many equity interests does the filing report Mr. Ogden owning after the grant?

He beneficially owns 78,250 option shares and 39,150 PSUs, all held directly.

What is the filing date and signature date on the Form 4?

The Form 4 reports transactions dated 09/26/2025 and is signed on 09/30/2025.