13G Filing: Perceptive Advisors and CytomX Therapeutics Inc (CTMX)

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CytomX Therapeutics Inc (NASDAQ:CTMX): Joseph Edelman’s Perceptive Advisors filed an amended 13D.

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You can access the original SEC filing by clicking here.

Ownership Summary Table

Name Sole Voting Power Shared Voting Power Sole Dispositive Power Shared Dispositive Power Aggregate Amount Owned Power Percent of Class
Perceptive Advisors 0 2,165,381 0 2,165,381 2,165,381 5.6%
Joseph Edelman 0 2,165,381 0 2,165,381 2,165,381 5.6%
Perceptive Life Sciences Master Fund, Ltd 0 2,165,381 0 2,165,381 2,165,381 5.6%

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Page 1 of 8 – SEC Filing

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No.    )*

CytomX
Therapeutics, Inc.

(Name of Issuer)

Common Stock, $0.00001 par value

(Title of Class of Securities)

23284F 10 5

(CUSIP
Number)

December 8, 2017

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to
designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☒ Rule 13d-1(c)

☐ Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting persons initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information
which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be
deemed to be filed for the purpose of Section 18 of the Securities Exchange Act of 1934 (Act) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act
(however, see the Notes).

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