# EDGAR Filing Document

**Accession Number:** 0001745020
**File Stem:** 0001104659-23-030325
**Filing Date:** 2023-3
**Character Count:** 18882
**Document Hash:** 3ea2edaaf63fe74fc51fd1a4c07512bb
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-23-030325.hdr.sgml**: 20230309

**ACCESSION NUMBER**: 0001104659-23-030325

**CONFORMED SUBMISSION TYPE**: S-8

**PUBLIC DOCUMENT COUNT**: 5

**FILED AS OF DATE**: 20230309

**DATE AS OF CHANGE**: 20230309

**EFFECTIVENESS DATE**: 20230309

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Theseus Pharmaceuticals, Inc.
- **CENTRAL INDEX KEY:** 0001745020
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **IRS NUMBER:** 830712806
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-8
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-270382
- **FILM NUMBER:** 23718189

**BUSINESS ADDRESS:**
- **STREET 1:** 314 MAIN STREET, SUITE 04-200
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** (857) 400-9491

**MAIL ADDRESS:**
- **STREET 1:** 314 MAIN STREET, SUITE 04-200
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142

**As filed with the Securities and Exchange Commission on March 9, 2023**

**Registration No. 333-** 

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, D.C. 20549**

------

**FORM S-8**

**REGISTRATION STATEMENT**

***Under***

***The Securities Act of 1933***

------

**THESEUS PHARMACEUTICALS, INC.**

**(Exact name of Registrant as specified in its charter)**

------

---

| | |
|:---|:---|
| **Delaware** | **83-0712806** |
| **(State or other jurisdiction of**<br> **incorporation or organization)** | **(IRS Employer**<br> **Identification No.)** |
| **314 Main Street** |  |
| **Cambridge, Massachusetts 02142** | **02142** |
| **(Address of Principal Executive Offices)** | **(Zip Code)** |

---

**Theseus Pharmaceuticals, Inc. 2021 Equity Incentive Plan**

**Theseus Pharmaceuticals, Inc. 2021 Employee Stock Purchase Plan**

**(Full title of Plan)**

**Timothy P. Clackson, Ph.D.**

**President and Chief Executive Officer**

**Theseus Pharmaceuticals, Inc.**

**314 Main Street**

**Cambridge, Massachusetts 02142**

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

**(857) 400-9491**

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

------

***Copies to:***

**Robert Puopolo, Esq.**<br> **Marishka DeToy, Esq.**<br> **Goodwin Procter, LLP**<br> **100 Northern Avenue**<br> **Boston, Massachusetts 02210**<br> **(617) 570-1000**<br>

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 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 | x | Smaller reporting company | x |
|  |  | Emerging growth company | x |

---

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. ¨

**EXPLANATORY NOTE**

**This Registration Statement on Form S-8 is filed to register the offer and sale of (i) an additional 1,936,722 shares of the Registrant's common stock, $0.001 par value per share, to be issued under the Registrant's 2021 Equity Incentive Plan and (ii) an additional 387,344 shares of the Registrant's common stock, $0.0001 par value per share, to be issued under the Registrant's 2021 Employee Stock Purchase Plan. This Registration Statement incorporates by reference the contents of the registration statement filed on [Form S-8](http://www.sec.gov/Archives/edgar/data/1745020/000119312521295571/d198307ds8.htm) (SEC File No. 333-260158) of the Registrant on October 8, 2021, and the registration relating to the Registrant's 2021 Equity Incentive Plan and 2021 Employee Stock Purchase Plan pursuant to General Instruction E.**

**PART II**

**INFORMATION REQUIRED IN THE REGISTRATION STATEMENT**

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| **Item 8.** | **Item 8.** | **Exhibits** |  |  |  |  |  |
|  | | | **Incorporated by Reference** | **Incorporated by Reference** | **Incorporated by Reference** | **Incorporated by Reference** |  |
| **<u>Exhibit</u> <br> <u>Number</u>** | **<u>Description</u>** | **<u>Description</u>** | **<u>Form</u>** | **<u>File No.</u>** | **<u>Exhibit</u>** | **<u>Filing Date</u>** | **<u>Filed Herewith</u>** |
| [4.1](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d1.htm) | [Amended and Restated Certificate of Incorporation of the Registrant, as currently in effect.](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d1.htm) | [Amended and Restated Certificate of Incorporation of the Registrant, as currently in effect.](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d1.htm) | [10-Q](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d1.htm) | [001-40869](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d1.htm) | [3.1](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d1.htm) | [August 11, 2022](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d1.htm) |  |
| [4.2](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d2.htm) | [Amended and Restated Bylaws of the Registrant, as currently in effect.](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d2.htm) | [Amended and Restated Bylaws of the Registrant, as currently in effect.](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d2.htm) | [10-Q](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d2.htm) | [001-40869](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d2.htm) | [3.2](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d2.htm) | [August 11, 2022](https://www.sec.gov/Archives/edgar/data/1745020/000155837022013178/thrx-20220630xex3d2.htm) |  |
| [5.1](tm238784d1_ex5-1.htm) | [Opinion of Goodwin Procter LLP.](tm238784d1_ex5-1.htm) | [Opinion of Goodwin Procter LLP.](tm238784d1_ex5-1.htm) |  |  |  |  | [X](tm238784d1_ex5-1.htm) |
| [23.1](tm238784d1_ex23-1.htm) | [Consent of Ernst & Young LLP, independent registered public accounting firm for the Registrant.](tm238784d1_ex23-1.htm) | [Consent of Ernst & Young LLP, independent registered public accounting firm for the Registrant.](tm238784d1_ex23-1.htm) |  |  |  |  | [X](tm238784d1_ex23-1.htm) |
| [23.2](tm238784d1_ex5-1.htm) | [Consent of Goodwin Procter LLP (contained in Exhibit 5.1).](tm238784d1_ex5-1.htm) | [Consent of Goodwin Procter LLP (contained in Exhibit 5.1).](tm238784d1_ex5-1.htm) |  |  |  |  | [X](tm238784d1_ex5-1.htm) |
| [24.1](#a_001) | [Power of Attorney (contained in the signature page to this Registration Statement).](#a_001) | [Power of Attorney (contained in the signature page to this Registration Statement).](#a_001) |  |  |  |  | [X](#a_001) |
| [99.1](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex103.htm) | [2021 Equity Incentive Plan and forms of equity agreements thereunder.](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex103.htm) | [2021 Equity Incentive Plan and forms of equity agreements thereunder.](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex103.htm) | [S-1/A](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex103.htm) | [333-259549](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex103.htm) | [10.3](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex103.htm) | [September 30, 2021](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex103.htm) |  |
| [99.2](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex104.htm) | [2021 Employee Stock Purchase Plan.](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex104.htm) | [2021 Employee Stock Purchase Plan.](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex104.htm) | [S-1/A](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex104.htm) | [333-259549](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex104.htm) | [10.4](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex104.htm) | [September 30, 2021](https://www.sec.gov/Archives/edgar/data/1745020/000119312521287286/d204007dex104.htm) |  |
| [107](tm238784d1_ex-filingfees.htm) | [Filing Fee Table.](tm238784d1_ex-filingfees.htm) | [Filing Fee Table.](tm238784d1_ex-filingfees.htm) |  |  |  |  | [X](tm238784d1_ex-filingfees.htm) |

---

**SIGNATURES**

Pursuant to the requirements of the Securities Act of 1933, 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 Cambridge, Massachusetts on this 9<sup>th</sup> day of March, 2023.

---

| | |
|:---|:---|
| **THESEUS PHARMACEUTICALS, INC.** | **THESEUS PHARMACEUTICALS, INC.** |
| By: | /s/ Timothy P. Clackson, Ph.D.  |
|  | Timothy P. Clackson, Ph.D. |
|  | President and Chief Executive Officer |

---

**<u>POWER OF ATTORNEY</u>**

KNOW ALL PERSONS BY THESE PRESENTS that each person whose signature appears below constitutes and appoints Timothy P. Clackson, Ph.D. and Bradford D. Dahms and each of them, his or her true and lawful attorneys-in-fact and agents, each with full power of substitution and resubstitution, for him or her and 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 the same, with 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, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that each of said attorney-in-fact and agents or their substitute or substitutes may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, each of the undersigned has executed this Power of Attorney as of the date indicated.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

---

| | | |
|:---|:---|:---|
| Signature | Title | Date |
| /s/ Timothy P. Clackson, Ph.D.<br> Timothy P. Clackson, Ph.D. | President, Chief Executive Officer and Director<br> (Principal Executive Officer) | March 9, 2023 |
| /s/ Bradford D. Dahms<br> Bradford D. Dahms | Chief Financial Officer<br> (Principal Financial and Accounting Officer) | March 9, 2023 |
| /s/ Iain D. Dukes, MA, D.Phil.<br> Iain D. Dukes, MA, D.Phil. | Chairman and Director | March 9, 2023 |
| /s/ Carl Gordon, Ph.D.<br> Carl Gordon, Ph.D. | Director | March 9, 2023 |
| /s/ Donald J. Hayden | Director | March 9, 2023 |
| Donald J. Hayden |  |  |
| /s/ Michael Rome, Ph.D.<br> Michael Rome, Ph.D. | Director | March 9, 2023 |
| /s/ Steven Stein, M.D.<br> Steven Stein, M.D. | Director | March 9, 2023 |
| /s/ Kathy Yi<br> Kathy Yi | Director | March 9, 2023 |

---

## Exhibit 5.1

**Exhibit 5.1**

---

| | |
|:---|:---|
| ![](tm238784d1_ex5-1img001.jpg) | Goodwin Procter LLP<br> 100 Northern Avenue <br> Boston, MA 02210<br>goodwinlaw.com <br> +1 617 570 1000 |

---

March 9, 2023

Theseus Pharmaceuticals, Inc.

314 Main Street

Cambridge, MA 02142

Re: <u>Securities Being Registered under Registration Statement on Form S-8</u>

We have acted as counsel to you in connection with your filing of a Registration Statement on Form S-8 (the "Registration Statement") pursuant to the Securities Act of 1933, as amended (the "Securities Act"), on or about the date hereof relating to an aggregate of 2,324,066 shares (the "Shares") of Common Stock, $0.0001 par value per share ("Common Stock"), of Theseus Pharmaceuticals, Inc., a Delaware corporation (the "Company"), that may be issued pursuant to the Company's 2021 Equity Incentive Plan and 2021 Employee Stock Purchase Plan (collectively, the "Plans").

We have reviewed such documents and made such examination of law as we have deemed appropriate to give the opinions set forth below. We have relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinion set forth below, on certificates of officers of the Company.

The opinion set forth below is limited to the Delaware General Corporation Law.

For purposes of the opinion set forth below, we have assumed that no event occurs that causes the number of authorized shares of Common Stock available for issuance by the Company to be less than the number of then unissued Shares.

Based on the foregoing, we are of the opinion that the Shares have been duly authorized and, upon issuance and delivery against payment therefor in accordance with the terms of the Plans, will be validly issued, fully paid and nonassessable.

This opinion letter and the opinion it contains shall be interpreted in accordance with the Core Opinion Principles as published in 74 *Business Lawyer* 815 (Summer 2019).

We hereby consent to the inclusion of this opinion as Exhibit 5.1 to the Registration Statement. In giving our consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

Theseus Pharmaceuticals, Inc.

March 9, 2023

---

| |
|:---|
| Very truly yours, |
| /s/ Goodwin Procter LLP |
| GOODWIN PROCTER 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 2021 Equity Incentive Plan and 2021 Employee Stock Purchase Plan of Theseus Pharmaceuticals, Inc. of our report dated March 9, 2023, with respect to the consolidated financial statements of Theseus Pharmaceuticals, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2022, filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP

Boston, Massachusetts

March 9, 2023

## Ex-Filing

**Exhibit 107**

**Calculation of Filing Fee Table**

**Form S-8**

(Form Type)

**Theseus Pharmaceuticals, Inc.**

(Exact Name of Registrant as Specified in its Charter)

<u>Table 1: Newly Registered Securities</u>

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| **Security**<br> **Type** | **Security Class Title** | **Fee Calculation**<br> **Rule** | **Amount**<br> **Registered (1)** | **Proposed**<br> **Maximum**<br> **Offering Price**<br> **per Unit** | **Maximum**<br> **Aggregate**<br> **Offering Price** | **Fee Rate** | **Amount of**<br> **Registration Fee** |
| Equity | 2021 Equity Incentive Plan, Common Stock, par value $0.0001 per share | Other (2) | 1936722 (3) | $9.07 (2) | $17566068.54 | $0.00011020 | $1935.79 |
| Equity | 2021 Employee Stock Purchase Plan, Common Stock, par value $0.0001 per share | Other (4) | 387344 (5) | $7.71 (4) | $2986422.24 | $0.00011020 | $329.11 |
| **Total Offering Amounts** | **Total Offering Amounts** | **Total Offering Amounts** | **Total Offering Amounts** |  | $20552490.78 |  | -- |
| **Total Fees Previously Paid** | **Total Fees Previously Paid** | **Total Fees Previously Paid** | **Total Fees Previously Paid** |  |  |  | -- |
| **Total Fee Offsets** | **Total Fee Offsets** | **Total Fee Offsets** | **Total Fee Offsets** |  |  |  | -- |
| **Net Fee Due** | **Net Fee Due** | **Net Fee Due** | **Net Fee Due** |  |  |  | $2264.90 |

---

(1) In accordance with Rule 416(a) under the Securities Act
 of 1933, as amended (the "Securities Act"), this registration statement shall be deemed to cover any additional securities
 that may from time to time be offered or issued to prevent dilution resulting from stock splits, stock dividends or similar transactions
 effected without the receipt of consideration which results in an increase in the number of our outstanding shares of common stock,
 $0.0001 par value per share ("Common Stock").

(2) The price of $9.07 per share, which is the average of
 the high and low sale prices of the Common Stock of the Registrant as quoted on the Nasdaq Global Select Market on March 6, 2023,
 is set forth solely for purposes of calculating the registration fee pursuant to Rules 457(c) and (h) of the Securities Act, and
 has been used as these shares are without a fixed price.

(3) Consists of 1,936,722 additional shares issuable under
 the 2021 Equity Incentive Plan (the "2021 Plan"), which represents the automatic annual increase to the number of shares
 available for issuance under the 2021 Plan effective as of January 1, 2023. Shares available for issuance under the 2021 Plan were
 previously registered on a registration statement on Form S-8 filed with the Securities and Exchange Commission on October 8, 2021
 (File No. 333-260158).

(4) The price of $7.71 per share, which is 85% of the average of the high and low sale
 prices of the Common Stock of the Registrant as quoted on the Nasdaq Global Select Market on March 7, 2023, is set forth solely
 for purposes of calculating the registration fee pursuant to Rules 457(c) and (h) of the Securities Act, and has been
 used as these shares are without a fixed price. Pursuant to the 2021 Employee Stock Purchase Plan (the "ESPP"), the purchase
 price of the shares of Common Stock reserved for issuance thereunder will be 85% of the fair market value of a share of Common Stock
 on the first trading day of the offering period or on the Purchase Date, whichever is less.

(5) Consists of 387,344 additional shares
 issuable under the 2021 ESPP, which represents the automatic annual increase to the number of shares available for issuance under
 the 2021 ESPP effective as of January 1, 2023. Shares available for issuance under the 2021 ESPP were previously registered
 on a registration statement on Form S-8 filed with the Securities and Exchange Commission on October 8, 2021 (File No. 333-260158).