# EDGAR Filing Document

**Accession Number:** 0001442836
**File Stem:** 0001104659-25-070245
**Filing Date:** 2025-7
**Character Count:** 12845
**Document Hash:** 9a622ff71f1074e8a6ece5df26ee4f2c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-070245.hdr.sgml**: 20250724

**ACCESSION NUMBER**: 0001104659-25-070245

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 13

**CONFORMED PERIOD OF REPORT**: 20250724

**ITEM INFORMATION**: Material Modifications to Rights of Security Holders

**ITEM INFORMATION**: Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20250724

**DATE AS OF CHANGE**: 20250724

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Mersana Therapeutics, Inc.
- **CENTRAL INDEX KEY:** 0001442836
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38129
- **FILM NUMBER:** 251144641

**BUSINESS ADDRESS:**
- **STREET 1:** 840 MEMORIAL DRIVE
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02139
- **BUSINESS PHONE:** 617-498-0020

**MAIL ADDRESS:**
- **STREET 1:** 840 MEMORIAL DRIVE
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02139

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MERSANA THERAPEUTICS INC
- **DATE OF NAME CHANGE:** 20080813

?xml version='1.0' encoding='ASCII'?

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**FORM 8-K**

**CURRENT REPORT**

**Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934**

Date of Report (Date of earliest event reported): **July 24, 2025**

**MERSANA THERAPEUTICS, INC.**

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

---

| | | |
|:---|:---|:---|
| **Delaware** | **001-38129** | **04-3562403** |
| **(State or other jurisdiction <br> of incorporation)** | **(Commission**<br> **File Number)**  | **(IRS Employer**<br> **Identification No.)**  |

---

---

| | |
|:---|:---|
| **840 Memorial Drive** **<br> Cambridge**, Massachusetts** | **02139** |
| **(Address of Principal Executive Offices)** | **(Zip Code)** |

---

Registrant's telephone number, including area code: **(617) 498-0020**

**Not Applicable**

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (<u>see</u> General Instruction A.2. below):

◻&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

◻&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

◻&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

◻&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

---

| | | |
|:---|:---|:---|
| **<u>Title of each class</u>** | **<u>Trading Symbol(s)</u>** | **<u>Name of each exchange on which registered</u>** |
| Common Stock, $0.0001 par value | MRSN | The Nasdaq Stock Market LLC |

---

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

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 13(a) of the Exchange Act. ◻

---

| | |
|:---|:---|
| **Item 3.03** | **Material Modification to Rights of Security Holders.** |

---

To the extent required by Item 3.03 of Form 8-K, the information contained in Item 5.03 of this Current Report on Form 8-K is incorporated herein by reference.

---

| | |
|:---|:---|
| **Item 5.03** | **Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year.** |

---

On July 24, 2025, Mersana Therapeutics, Inc. (the "Company") filed a Certificate of Amendment to the Company's Fifth Amended and Restated Certificate of Incorporation, as amended, (the "Certificate of Amendment") with the Secretary of State of the State of Delaware, which will effect, as of 5:00 p.m. Eastern Time, on July 25, 2025 (the "Effective Time"), a 1-for-25 reverse stock split (the "Reverse Stock Split") of the issued and outstanding shares of the Company's common stock, $0.0001 par value per share (the "Common Stock").

The Reverse Stock Split is intended, among other things, to bring the Company into compliance with the minimum bid price requirement for continued listing on the Nasdaq Global Select Market, as previously reported in the Company's definitive proxy statement for the Company's annual meeting of stockholders held on June 12, 2025, as filed with the Securities and Exchange Commission on April 29, 2025 (the "Proxy Statement").

At the Effective Time, every twenty-five shares of issued and outstanding Common Stock will be automatically reclassified and combined into one share of Common Stock. No fractional shares will be issued in connection with the Reverse Stock Split. Stockholders who would otherwise be entitled to a fractional share of Common Stock are instead entitled to receive a cash payment in lieu of such fractional shares.

The Reverse Stock Split will not change the number of authorized shares of Common Stock or the par value of the Common Stock. Proportionate adjustments will be made to the number of shares of Common Stock available for issuance under the Company's equity incentive plans, as well as the number of shares underlying, and the exercise prices of, outstanding equity awards under such plans, in accordance with their respective terms and as described in the Proxy Statement.

The Common Stock is expected to begin trading on a post-Reverse Stock Split basis at the market open on July 28, 2025 under the Company's existing trading symbol "MRSN". The new CUSIP number for the Common Stock following the Reverse Stock Split is 59045L205.

The foregoing description of the Certificate of Amendment does not purport to be complete and is qualified in its entirety by reference to the complete text of the Certificate of Amendment, a copy of which is attached hereto as Exhibit 3.1 and is incorporated herein by reference.

---

| | |
|:---|:---|
| **Item 9.01.** | **Financial Statements and Exhibits.** |

---

(d) Exhibits

---

| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| [3.1](tm2521489d1_ex3-1.htm) | [Certificate of Amendment to Fifth Amended and Restated Certificate of Incorporation, as amended, of Mersana Therapeutics, Inc.](tm2521489d1_ex3-1.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document). |

---

**SIGNATURES**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

---

| | | |
|:---|:---|:---|
|  | **MERSANA THERAPEUTICS, INC.** | **MERSANA THERAPEUTICS, INC.** |
| Date: July 24, 2025 | By: | /s/ Brian DeSchuytner |
|  |  | Brian DeSchuytner |
|  |  | Senior Vice President, Chief Operating Officer and Chief Financial Officer |

---

## Exhibit 3.1

**Exhibit 3.1**

**CERTIFICATE OF AMENDMENT<br> TO<br> FIFTH AMENDED AND RESTATED CERTIFICATE OF INCORPORATION, AS AMENDED<br> OF<br> MERSANA THERAPEUTICS, INC.**

**Pursuant to Section 242 of the<br> General Corporation Law of the State of Delaware**

**Mersana Therapeutics, Inc.** (hereinafter called the "Corporation"), a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware, does hereby certify as follows:

**FIRST:** A resolution was duly adopted by the Board of Directors of the Corporation pursuant to Section 242 of the General Corporation Law of the State of Delaware setting forth an amendment to the Fifth Amended and Restated Certificate of Incorporation, as amended, of the Corporation and declaring said amendment to be advisable. The stockholders of the Corporation duly approved and adopted said proposed amendment at a meeting of stockholders in accordance with Section 242 of the General Corporation Law of the State of Delaware. The resolution setting forth the amendment is as follows:

RESOLVED: That section (a) of Article IV of the Fifth Amended and Restated Certificate of Incorporation, as amended, of the Corporation be and hereby is deleted in its entirety and the following is inserted in lieu thereof:

"(a) <u>Authorized Shares</u>.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i) The total number of shares of stock which the Corporation shall have authority to issue is 375,000,000, consisting of 350,000,000
shares of Common Stock, par value $0.0001 per share ("Common Stock"), and 25,000,000 shares of Preferred Stock, par value
$0.0001 per share ("Preferred Stock"). Such stock may be issued from time to time by the Corporation for such consideration
as may be fixed by the board of directors of the Corporation (the "Board of Directors").

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii) Effective upon the effective time of this Certificate of Amendment to the Restated Certificate of Incorporation (the "Certificate
of Amendment") (the "Effective Time"), a one-for-twenty-five reverse stock split of the Common Stock shall become effective,
pursuant to which each twenty-five (the "Reverse Stock Split Number") shares of Common Stock issued and outstanding and held
of record by each stockholder of the Corporation or issued and held by the Corporation in treasury immediately prior to the Effective
Time shall be reclassified and combined into one (1) validly issued, fully paid and nonassessable share of Common Stock automatically
and without any action by the holder thereof and shall represent one share of Common Stock from and after the Effective Time (such reclassification
and combination of shares, the "Reverse Stock Split"). The par value of the Common Stock following the Reverse Stock Split
shall remain at $0.0001 par value per share. No fractional shares of Common Stock shall be issued as a result of or in connection with
the Reverse Stock Split. Stockholders of record who otherwise would be entitled to receive a fractional share of Common Stock as a result
of the Reverse Stock Split, following the Effective Time, shall be entitled to receive a cash payment (without interest) in lieu of such
fractional share equal to the fraction of a share of Common Stock to which such holder would otherwise be entitled multiplied by (i) the
closing price per share of the Common Stock on the Nasdaq Global Select Market at the close of business on the trading day preceding the
date of the Effective Time multiplied by (ii) the Reverse Stock Split Number.

Each stock certificate or book entry position that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares formerly represented by such certificate or book entry position have been reclassified as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time; provided, however, that each stockholder of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new book entry position evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been reclassified."

**SECOND:** This Certificate of Amendment shall be effective at 5:00 p.m., Eastern Time, on July 25, 2025.

**\*\*\***

**IN WITNESS WHEREOF**, this Certificate of Amendment has been executed by a duly authorized officer of the Corporation on this 24th day of July, 2025.

---

| |
|:---|
| **Mersana Therapeutics, Inc.** |
| /s/ Martin Huber, M.D. |
| By: Martin Huber, M.D. |
| Title: President and Chief Executive Officer |

---