# EDGAR Filing Document

**Accession Number:** 0001501989
**File Stem:** 0001193125-25-175473
**Filing Date:** 2025-8
**Character Count:** 18815
**Document Hash:** 9b49ab87e4583dba0ab58f2def85814e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-175473.hdr.sgml**: 20250807

**ACCESSION NUMBER**: 0001193125-25-175473

**CONFORMED SUBMISSION TYPE**: S-8

**PUBLIC DOCUMENT COUNT**: 16

**FILED AS OF DATE**: 20250807

**DATE AS OF CHANGE**: 20250807

**EFFECTIVENESS DATE**: 20250807

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** CytomX Therapeutics, Inc.
- **CENTRAL INDEX KEY:** 0001501989
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 273521219
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-8
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-289370
- **FILM NUMBER:** 251194603

**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

**As filed with the Securities and Exchange Commission on August 7, 2025** 

**Registration No. 333-** 

**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

**FORM S-8** 

**REGISTRATION STATEMENT** 

***UNDER***

***THE SECURITIES ACT OF 1933***

## CytomX Therapeutics, Inc.
**(Exact name of Registrant as specified in its charter)** 

---

| | |
|:---|:---|
| **Delaware** | **27-3521219** |
| **(State or other jurisdiction of<br>incorporation or organization)** | **(I.R.S. Employer<br>Identification No.)** |

---

**151 Oyster Point Blvd., Suite 400** 

**South San Francisco, CA 94080** 

**(Address of Principal Executive Offices) (Zip Code)** 

**CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan** 

**(Full Title of the Plan)** 

**Sean A. McCarthy, D.Phil.** 

**President and Chief Executive Officer** 

**CytomX Therapeutics, Inc.** 

**151 Oyster Point Blvd., Suite 400** 

**South San Francisco, CA 94080** 

**(650) 515-3185** 

**(Name and address of agent for service)** 

**(Telephone number, including area code, of agent for service)** 

***Copies to:***

**Mark V. Roeder, Esq.** 

**John C. Williams, Esq.** 

**Latham & Watkins LLP** 

**140 Scott Drive** 

**Menlo Park, California 94025** 

**(650) 328-4600** 

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

---

| | | | |
|:---|:---|:---|:---|
| Large accelerated filer | ☐ | Accelerated filer | ☒ |
| Non-accelerated filer | ☐ | Smaller reporting company | ☒ |
|  |  | Emerging growth company | ☐ |

---

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

**Proposed sale to take place as soon after the effective date of the** 

**registration statement as awards under the plans are exercised and/or vest.** 

------

**EXPLANATORY NOTE** 

This Registration Statement on Form S-8 is being filed for the purpose of registering an additional 4,381,320 shares of the Registrant's common stock issuable under the following employee benefit plan for which Registration Statements of the Registrant on Form S-8 (File Nos. 333-207694, 333-209992, 333-215795, 333-223491, 333-229916, 333-236711, 333-253452, 333-263321, 333-270869, 333-277819 and 333-285594) are effective: the CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan, as a result of the amendment and restatement of such plan, which added 4,381,320 shares of common stock.

**INCORPORATION BY REFERENCE OF CONTENTS OF** 

**REGISTRATION STATEMENT ON FORM S-8**

Pursuant to Instruction E of Form S-8, the contents of the Registration Statements on Form S-8 filed with the Securities and Exchange Commission on [<u>October</u> <u>30, 2015</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312515360038/d205218ds8.htm) (File No. 333-207694), [<u>March</u> <u>7, 2016</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312516495280/d155038ds8.htm) (File No. 333-209992), [<u>January</u> <u>27, 2017</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312517022008/d294863ds8.htm) (File No. 333-215795), [<u>March</u> <u>7, 2018</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312518073612/d545328ds8.htm) (File No. 333-223491), [<u>February</u> <u>27, 2019</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312519054171/d701915ds8.htm) (File No. 333-229916), [<u>February</u> <u>27, 2020</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312520052872/d893269ds8.htm) (File No. 333-236711), [<u>February</u> <u>24, 2021</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312521054696/d134950ds8.htm) (File No. 333-253452), [<u>March</u> <u>4, 2022</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312522066309/d239385ds8.htm) (File No. 333-263321), [<u>March</u> <u>27, 2023</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312523080477/d492639ds8.htm) (333-270869), [<u>March</u> <u>11, 2024</u>](http://www.sec.gov/Archives/edgar/data/1501989/000119312524064845/d760313ds8.htm) (333-277819) and [March 6, 2025](http://www.sec.gov/Archives/edgar/data/1501989/000119312525048412/d897389ds8.htm) (File No. 333-285594) are incorporated by reference herein; except for Item 8 which is being updated by this Registration Statement.

**Item 8. Exhibits** 

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| | | **Incorporated by Reference** | **Incorporated by Reference** | **Incorporated by Reference** | |
| <br>**Exhibit<br>Number** | <br>**Exhibit Description** | **Form** | **Date** | **Number** |<br>**Filed<br>Herewith** |
| 4.1 | [Amended and Restated Certificate of Incorporation.](http://www.sec.gov/Archives/edgar/data/1501989/000119312524141699/d816353dex31.htm) | 8-K | 5/17/2024 | 3.1 |  |
| 4.2 | [Amended and Restated Bylaws.](http://www.sec.gov/Archives/edgar/data/1501989/000119312524075211/d803852dex31.htm) | 8-K | 3/22/2024 | 3.1 |  |
| 4.3 | [Form of Common Stock Certificate.](http://www.sec.gov/Archives/edgar/data/1501989/000119312515329662/d948537dex41.htm) | S-1/A | 9/28/2015 | 4.1 |  |
| 4.4 | [Registration Rights Agreement dated as of September 29, 2017 by and between CytomX Therapeutics, Inc. and Amgen, Inc.](http://www.sec.gov/Archives/edgar/data/1501989/000156459017022252/ctmx-ex44_91.htm) | 10-Q | 11/7/2017 | 4.4 |  |
| 5.1 | [Opinion of Latham & Watkins LLP.](d119770dex51.htm) |  |  |  | X |
| 23.1 | [Consent of Independent Registered Public Accounting Firm.](d119770dex231.htm) |  |  |  | X |
| 23.2 | [Consent of Latham & Watkins LLP (included in Exhibit 5.1).](d119770dex51.htm) |  |  |  | X |
| 24.1 | [Power of Attorney. Reference is made to the signature page to the Registration Statement.](d119770ds8.htm#sig) |  |  |  | X |
| 99.1(a)# | [CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan.](http://www.sec.gov/Archives/edgar/data/1501989/000119312525140739/d948514dex101.htm) | 8-K | 6/13/2025 | 10.1 |  |
| 99.1(b)# | [Form of Option Award Notice under the CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan.](http://www.sec.gov/Archives/edgar/data/1501989/000156459015010977/ctmx-ex104_591.htm) | 10-Q | 11/23/2015 | 10.4 |  |
| 99.1(c)# | [Form of Early Exercise Option Award Notice under the CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan.](http://www.sec.gov/Archives/edgar/data/1501989/000156459015010977/ctmx-ex105_592.htm) | 10-Q | 11/23/2015 | 10.5 |  |
| 99.1(d)# | [Form of Restricted Share Unit Award Grant Notice and Agreement under the CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan.](http://www.sec.gov/Archives/edgar/data/1501989/000095017022002519/ctmx-ex10_3.htm) | 10-K | 3/1/2022 | 10.3 (d) |  |
| 107 | [Filing Fee Table.](d119770dexfilingfees.htm) |  |  |  | X |

---

# Indicates management contract or compensatory plan.

------

**SIGNATURES** 

Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in South San Francisco, State of California, on August 7, 2025.

---

| | |
|:---|:---|
|  **CytomX Therapeutics, Inc.** | **CytomX Therapeutics, Inc.** |
| By: | /s/ Sean A. McCarthy |
|  | Sean A. McCarthy, D.Phil. |
|  | President and Chief Executive Officer |

---

**POWER OF ATTORNEY** 

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below does hereby constitute and appoint Sean A. McCarthy and Christopher W. Ogden, and each of them, with full power of substitution and full power to act without the other, his or her true and lawful attorney-in-fact and agent to act for him or her in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement, and to file this registration statement, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in order to effectuate the same as fully, to all intents and purposes, as they or he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons in the capacities and on the date indicated.

---

| | | |
|:---|:---|:---|
| **Signature** | **Title** | **Date** |
| /s/ Sean A. McCarthy<br> Sean A. McCarthy, D.Phil. | President, Chief Executive Officer and Chairman <br>*(Principal Executive Officer)* | August 7, 2025 |
| /s/ Christopher W. Ogden<br> Christopher W. Ogden | Chief Financial Officer <br>*(Principal Financial Officer and Principal Accounting Officer)* | August 7, 2025 |
| /s/ Matthew P. Young<br> Matthew P. Young | Director | August 7, 2025 |
| /s/ Alan Ashworth<br> Alan Ashworth, Ph.D. FRS | Director | August 7, 2025 |
| /s/ James R. Meyers<br> James R. Meyers | Director | August 7, 2025 |
| /s/ Elaine V. Jones<br> Elaine V. Jones, Ph.D. | Director | August 7, 2025 |
| /s/ Halley E. Gilbert<br> Halley E. Gilbert | Director | August 7, 2025 |
| /s/ Mani Mohindru<br> Mani Mohindru, Ph.D. | Director | August 7, 2025 |
| /s/ Zhen Su<br> Zhen Su, M.D. | Director | August 7, 2025 |

---

## Exhibit 5.1

**Exhibit 5.1** 

---

| | | |
|:---|:---|:---|
| ![LOGO](g119770g0802073541310.jpg) | 140 Scott Drive<br> Menlo Park, California 94025<br> Tel: +1.650.328.4600 Fax: +1.650.463.2600<br> www.lw.com<br>FIRM / AFFILIATE OFFICES | 140 Scott Drive<br> Menlo Park, California 94025<br> Tel: +1.650.328.4600 Fax: +1.650.463.2600<br> www.lw.com<br>FIRM / AFFILIATE OFFICES |
| ![LOGO](g119770g0802073541310.jpg) | Austin | Milan |
| ![LOGO](g119770g0802073541310.jpg) | Beijing | Munich |
| ![LOGO](g119770g0802073541310.jpg) | Boston | New York |
| ![LOGO](g119770g0802073541310.jpg) | Brussels | Orange County |
| ![LOGO](g119770g0802073541310.jpg) | Century City | Paris |
|  | Chicago | Riyadh |
|  | Dubai | San Diego |
|  | Düsseldorf | San Francisco |
|  | Frankfurt | Seoul |
|  | Hamburg | Silicon Valley |
| August 7, 2025 | Hong Kong | Singapore |
|  | Houston | Tel Aviv |
|  | London | Tokyo |
|  | Los Angeles | Washington, D.C. |
|  | Madrid |  |

---

CytomX Therapeutics, Inc.

151 Oyster Point Blvd., Suite 400

South San Francisco, CA 94080

---

| | |
|:---|:---|
| Re: | Registration Statement on Form S-8; 4,381,320 shares of Common Stock of CytomX Therapeutics, Inc., par value $0.00001 per share  |

---

To the addressee set forth above:

We have acted as special counsel to CytomX Therapeutics, Inc., a Delaware corporation (the "***Company***"), in connection with the registration by the Company of an aggregate of 4,381,320 shares (the "***Shares***") of common stock of the Company, par value $0.00001 per share, issuable under the CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan (the "***2015 Plan***").

The Shares are included in a registration statement on Form S-8 under the Securities Act of 1933, as amended (the "***Act***"), filed with the Securities and Exchange Commission (the "***Commission***") on August 7, 2025 (the "***Registration Statement***"). This opinion is being furnished in connection with the requirements of Item 601(b)(5) of Regulation S-K under the Act, and no opinion is expressed herein as to any matter pertaining to the contents of the Registration Statement or the related prospectuses, other than as expressly stated herein with respect to the issue of the Shares.

As such counsel, we have examined such matters of fact and questions of law as we have considered appropriate for purposes of this letter. With your consent, we have relied upon certificates and other assurances of officers of the Company and others as to factual matters without having independently verified such factual matters. We are opining herein as to the General Corporation Law of the State of Delaware (the "***DGCL***"), and we express no opinion with respect to any other laws.

Subject to the foregoing and the other matters set forth herein, it is our opinion that, as of the date hereof, when the Shares shall have been duly registered on the books of the transfer agent and registrar therefor in the name or on behalf of the purchasers and have been issued by the Company against payment therefor in the circumstances contemplated by the 2015 Plan, assuming in each case that the individual issuances, grants or awards under the 2015 Plan are duly authorized

------

**August 7, 2025** 

**Page 2**![LOGO](g119770g0802073541189.jpg)

by all necessary corporate action and duly issued, granted or awarded and exercised in accordance with the requirements of law and the 2015 Plan (and the agreements and awards duly adopted thereunder and in accordance therewith), the issuance and sale of the Shares will have been duly authorized by all necessary corporate action of the Company, and the Shares will be validly issued, fully paid and nonassessable. In rendering the foregoing opinion, we have assumed that the Company will comply with all applicable notice requirements regarding uncertificated shares provided in the DGCL.

This opinion is for your benefit in connection with the Registration Statement and may be relied upon by you and by persons entitled to rely upon it pursuant to the applicable provisions of the Act. We consent to your filing this opinion as an exhibit to the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission thereunder.

---

| |
|:---|
| Sincerely, |
| /s/ Latham & Watkins LLP |

---

## Exhibit 23.1

**Exhibit 23.1** 

**CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM** 

We consent to the incorporation by reference in the Registration Statement (Form S-8) pertaining to the CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan of our reports dated March 6, 2025, with respect to the financial statements of CytomX Therapeutics, Inc. and the effectiveness of internal control over financial reporting of CytomX Therapeutics, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2024, filed with the Securities and Exchange Commission.

---

| |
|:---|
| /s/ Ernst & Young LLP |
| San Francisco, California<br> August 7, 2025 |

---

## Ex-Filing

?xml version='1.0' encoding='ASCII'? EX-FILING FEES

---

| |
|:---|
| **Calculation of Filing Fee Tables**  |
| &nbsp;&nbsp;&nbsp;&nbsp;**S-8**  |
| &nbsp;&nbsp;&nbsp;&nbsp;**CytomX Therapeutics, Inc.**  |

---

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Security Type**  | **Security Class Title**  | **Fee Calculation Rule**  | **Amount Registered**  | **Proposed Maximum Offering Price Per Unit**  | **Maximum Aggregate Offering Price**  | **Fee Rate**  | **Amount of Registration Fee**  |
| 1 | Equity | Common Stock, par value $0.00001 per share | Other | 4381320 | $2.29 | $10033222.80 | 0.0001531 | $1536.09 |
| Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: |  | $10033222.80  |  | $1536.09  |
| Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  |  |  |  | $0.00  |
| Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  |  |  |  | $1536.09  |

---

 **Offering Note** <br>

<sup>1</sup> Note 1(a). Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this registration statement shall also cover any additional shares of the Registrant's common stock that become issuable under the CytomX Therapeutics, Inc. Amended and Restated 2015 Equity Incentive Plan (the "2015 Plan") by reason of any stock dividend, stock split, recapitalization or similar transaction effected without the Registrant's receipt of consideration which would increase the number of outstanding shares of common stock. Note 1(b). Proposed Maximum Offering Price Per Unit is made pursuant to Rules 457(c) and 457(h) of the Securities Act solely for purposes of calculating the registration fee. The Proposed Maximum Offering Price Per Share for shares available for future grant is the average of the high and low prices for the Registrant's common stock as reported on The Nasdaq Global Select Market on August 1, 2025. Note 1(c). Amount Registered represents the additional shares of common stock available for future issuance under the 2015 Plan resulting from the amendment and restatement of the 2015 Plan as of June 11, 2025.

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| | |
|:---|:---|
| | |
| **Rule 457(p)** | **Rule 457(p)** |
| Fee Offset Claims | N/A |
| Fee Offset Sources | N/A |

---