SEC FORM 4

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

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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^*

McCarthy Sean A.

(Last)

(First)

(Middle)

C/O CYTOMX THERAPEUTICS, INC.

151 OYSTER POINT BLVD., SUITE 400

(Street)

SOUTH SAN FRANCISCO

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)

X	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	President and CEO

3. Date of Earliest Transaction (Month/Day/Year)
12/01/2017

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	11/30/2017		A⁽¹⁾	V	398	A	$12.1465	4,643	D
Common Stock	12/01/2017		M		4,100	A	$0.945	8,743	D
Common Stock	12/01/2017		M		10,240	A	$1.1339	18,983	D
Common Stock	12/01/2017		S⁽²⁾		14,340	D	$20.6⁽³⁾	4,643	D
Common Stock								158,737	I	See footnote⁽⁴⁾

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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Stock Option (right to buy)	$0.945	12/01/2017		M			4,100	⁽⁵⁾	02/25/2023	Common Stock	4,100	$0.00	115,193	D
Stock Option (right to buy)	$1.1339	12/01/2017		M			10,240	⁽⁵⁾	09/20/2021	Common Stock	10,240	$0.00	356,721	D

Explanation of Responses:

1. 398 shares were acquired pursuant to the Issuer's Employee Stock Purchase Plan in a transaction that was exempt under both Rule 16b-3(d) and Rule 16b-3(c).

2. The sale was effected pursuant to the Reporting Person's Rule 10b5-1 trading plan.

3. The price reported in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $20.42 to $20.78, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

4. Held in McCarthy Family Trust dated August 9, 2001, Sean A. McCarthy and Jeanette J. McCarthy, Trustees.

5. 100% of the shares subject to the option are fully vested and exercisable.

	/s/ Cynthia J. Ladd, as Attorney-in-Fact for Sean A. McCarthy	12/05/2017
	** 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).
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