<SEC-DOCUMENT>0000899243-17-007785-index.html : 20170316
<SEC-HEADER>0000899243-17-007785.hdr.sgml : 20170316
<ACCEPTANCE-DATETIME>20170316173024
ACCESSION NUMBER:		0000899243-17-007785
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170315
FILED AS OF DATE:		20170316
DATE AS OF CHANGE:		20170316

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CytomX Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001501989
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				273521219
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		151 OYSTER POINT BLVD.
		STREET 2:		SUITE 400
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
		BUSINESS PHONE:		650.515.3185

	MAIL ADDRESS:	
		STREET 1:		151 OYSTER POINT BLVD.
		STREET 2:		SUITE 400
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			TEPPER ROBERT I
		CENTRAL INDEX KEY:			0001192595

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37587
		FILM NUMBER:		17695622

	MAIL ADDRESS:	
		STREET 1:		40 LANDSDOWNE STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STARR KEVIN P
		CENTRAL INDEX KEY:			0001192603

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37587
		FILM NUMBER:		17695623

	MAIL ADDRESS:	
		STREET 1:		75 SIDNEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LEVIN MARK J
		CENTRAL INDEX KEY:			0001180428

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37587
		FILM NUMBER:		17695624

	MAIL ADDRESS:	
		STREET 1:		40 LANDSDOWNE STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			TRV GP, LLC
		CENTRAL INDEX KEY:			0001578973
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37587
		FILM NUMBER:		17695625

	BUSINESS ADDRESS:	
		STREET 1:		C/O THIRD ROCK VENTURES
		STREET 2:		29 NEWBURY STREET, 3RD FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
		BUSINESS PHONE:		617-585-2000

	MAIL ADDRESS:	
		STREET 1:		C/O THIRD ROCK VENTURES
		STREET 2:		29 NEWBURY STREET, 3RD FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Third Rock Ventures GP, L.P.
		CENTRAL INDEX KEY:			0001578976
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37587
		FILM NUMBER:		17695626

	BUSINESS ADDRESS:	
		STREET 1:		C/O THIRD ROCK VENTURES
		STREET 2:		29 NEWBURY STREET, 3RD FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
		BUSINESS PHONE:		617-585-2000

	MAIL ADDRESS:	
		STREET 1:		C/O THIRD ROCK VENTURES
		STREET 2:		29 NEWBURY STREET, 3RD FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			THIRD ROCK VENTURES LP
		CENTRAL INDEX KEY:			0001408591
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37587
		FILM NUMBER:		17695627

	BUSINESS ADDRESS:	
		STREET 1:		29 NEWBURY STREET
		STREET 2:		SUITE 401
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
		BUSINESS PHONE:		617-859-3099

	MAIL ADDRESS:	
		STREET 1:		29 NEWBURY STREET
		STREET 2:		SUITE 401
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
Document 1 - file: doc4.html
Document 1 - RAW XML: doc4.xml
</DOCUMENT> </SEC-DOCUMENT>