# EDGAR Filing Document

**Accession Number:** 0001733294
**File Stem:** 0001558370-25-009290
**Filing Date:** 2025-7
**Character Count:** 17527
**Document Hash:** 561dc4cf345bf6fe860529992902613e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001558370-25-009290.hdr.sgml**: 20250718

**ACCESSION NUMBER**: 0001558370-25-009290

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 16

**CONFORMED PERIOD OF REPORT**: 20250718

**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**: 20250718

**DATE AS OF CHANGE**: 20250718

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Generation Bio Co.
- **CENTRAL INDEX KEY:** 0001733294
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 814301281
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-39319
- **FILM NUMBER:** 251132678

**BUSINESS ADDRESS:**
- **STREET 1:** 301 BINNEY STREET
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 857-529-5908

**MAIL ADDRESS:**
- **STREET 1:** 301 BINNEY STREET
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142

?xml version='1.0' encoding='ASCII'? Generation Bio Co._July 18, 2025

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**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 18, 2025**

## Generation Bio Co.
**(Exact Name of Registrant as Specified in Charter)**

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| | | | | |
|:---|:---|:---|:---|:---|
| **Delaware** |  | **001-39319** |  | **81-4301284** |
| **(State or Other Jurisdiction**<br>**of Incorporation)** |  | **(Commission**<br>**File Number)** |  | **(IRS Employer**<br>**Identification No.)** |

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| | | |
|:---|:---|:---|
| **301 Binney Street**<br>**Cambridge, MA** |  | **02142**  |
| **(Address of Principal Executive Offices)** |  | **(Zip Code)** |

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**Registrant's telephone number, including area code: (617) 655-7500**

**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 (*see* General Instruction A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

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

☐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:

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| | | |
|:---|:---|:---|
| **Title of each class** | **Trading Symbol(s)** | **Name of each exchange on which registered** |
| **Common Stock, $0.0001 par value per share** | **GBIO** | **Nasdaq Global Select Market** |

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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. ☐

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**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 18, 2025, Generation Bio Co. (the "Company") filed a Certificate of Amendment to the Company's Amended and Restated Certificate of Incorporation (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 21, 2025 (the "Effective Time"), a 1-for-10 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 to, among other things, 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 4, 2025, as filed with the Securities and Exchange Commission on April 23, 2025 (the "Proxy Statement").

At the Effective Time, every 10 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 and 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 22, 2025 under the Company's existing trading symbol "GBIO". The new CUSIP number for the Common Stock following the Reverse Stock Split is 37148K 209.

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.

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

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(d) Exhibits

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| | |
|:---|:---|
| **Exhibit**<br>**No.** | **Description** |
| 3.1 | [Certificate of Amendment of Amended and Restated Certificate of Incorporation of Generation Bio Co.](gbio-20250718xex3d1.htm) |
| 99.1 | [Press Release Issued by Generation Bio Co. on July 18, 2025.](gbio-20250718xex99d1.htm) |
| 104 | Cover Page Interactive Data File (formatted as Inline XBRL) |

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

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| | | |
|:---|:---|:---|
|  | GENERATION BIO CO. | GENERATION BIO CO. |
| Date: July 18, 2025 | By: | /s/ Geoff McDonough |
|  |  | Name: Geoff McDonough, M.D. |
|  |  | Title: President and Chief Executive Officer |

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## Exhibit 3.1

**Exhibit 3.1**

CERTIFICATE OF AMENDMENT

TO THE

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

GENERATION BIO CO.

Generation Bio Co., a corporation organized and existing under the General Corporation Law of the State of Delaware (the "Corporation"), hereby certifies as follows:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1. The name of the Corporation is Generation Bio Co. The date of filing of the Corporation's original Certificate of Incorporation with the Secretary of State of the State of Delaware was October 21, 2016, under the name Torus Therapeutics, Inc.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2. This Certificate of Amendment to the Amended and Restated Certificate of Incorporation, filed with the Secretary of State of the State of Delaware on June 16, 2020, was adopted in accordance with Section 242 of the General Corporation Law of the State of Delaware, and has been duly approved by the stockholders of the Corporation.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3. Article FOURTH of the Amended and Restated Certificate of Incorporation is hereby amended to add the following:

"Effective upon the effectiveness of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation of the Corporation with the Secretary of State of the State of Delaware (the "Effective Time"), a one for ten reverse stock split of the Common Stock shall become effective, pursuant to which each ten (the "Reverse Stock Split Number") shares of Common Stock issued and outstanding immediately prior to the Effective Time shall be automatically reclassified, changed and combined into one (1) validly issued, fully paid and non-assessable share of Common Stock, the exact ratio within the foregoing range to be determined by the board of directors prior to the Effective Time and publicly announced by the Corporation, without any further action by the Corporation or the holder thereof (the "Reverse Stock Split"); provided that no fractional shares of Common Stock shall be issued to any holder in connection with the Reverse Stock Split and in lieu thereof, any stockholder who otherwise would be entitled to receive fractional shares of Common Stock (taking into account all shares of capital stock owned by such stockholder) shall be entitled to receive cash (without interest or deduction) equal to the fraction of one share of Common Stock to which such stockholder would otherwise be entitled multiplied by the closing price of the Common Stock as reported on the Nasdaq Global Select Market at the close of business on the trading day immediately preceding the date of the Effective Time multiplied by the Reverse Stock Split Number."

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4. This Certificate of Amendment to the Amended and Restated Certificate of Incorporation shall be effective at 5:00 p.m., Eastern Time, on July 21, 2025.

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IN WITNESS WHEREOF, the Corporation has caused this Certificate of Amendment to the Amended and Restated Certificate of Incorporation to be signed by its Chief Executive Officer and President on July 18, 2025.

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| | |
|:---|:---|
| /<br>|  |
|  | **GENERATION BIO CO.** |
|  | /s/ Geoff McDonough |
|  | Geoff McDonough, M.D. |
|  | *President and Chief Executive Officer* |

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## Exhibit 99.1

**Exhibit 99.1**

![Graphic](gbio-20250718xex99d1001.jpg)

**Generation Bio Announces 1-for-10 Reverse Stock Split**

**CAMBRIDGE, Mass**. – July 18, 2025 – Generation Bio Co. (Nasdaq: GBIO), a biotechnology company working to change what's possible for people living with T cell-driven autoimmune diseases, today announced that it will implement a 1-for-10 reverse stock split of the issued shares of the Company's common stock ("Reverse Stock Split"), effective at 5:00 pm Eastern Time on July 21, 2025. The Reverse Stock Split was approved by the Company's stockholders at the Company's Annual Meeting of Stockholders held on June 4, 2025, with the final ratio subsequently determined by the Company's Board of Directors. One of the primary goals of the Reverse Stock Split is to increase the per-share market price of the Company's common stock to enable the Company to regain compliance with the minimum bid price requirement for continued listing on the Nasdaq Global Select Market.

The Company's common stock is expected to begin trading on a split-adjusted basis when the markets open on July 22, 2025 under the Company's existing trading symbol "GBIO" with the new CUSIP number 37148K 209.

At the effective time of the Reverse Stock Split, every ten shares of the Company's issued and outstanding common stock will be automatically reclassified and combined into 1 share of common stock. This will reduce the number of issued and outstanding shares of common stock from approximately 67.3 million shares to approximately 6.7 million shares. The Reverse Stock Split will not change the number of authorized shares of the Company's 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 and 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 Company's proxy statement for the Annual Meeting of Stockholders as filed with the Securities and Exchange Commission on April 23, 2025 (the "Proxy Statement").

No fractional shares will be issued, if, as a result of the Reverse Stock Split, a stockholder would otherwise become entitled to a fractional share because the number of shares of common stock they hold before the Reverse Stock Split is not evenly divisible by the split ratio. Instead, each stockholder will be entitled to receive a cash payment in lieu of a fractional share.

Computershare Trust Company, N.A., is acting as the exchange agent and transfer agent for the Reverse Stock Split. Stockholders holding their shares electronically are not required to take any action to receive post-split shares. Stockholders owning shares through a bank, broker or other nominee will have their positions adjusted to reflect the Reverse Stock Split and will receive payment for any fractional shares in accordance with their respective bank's, broker's, or nominee's particular processes.

Additional information about the Reverse Stock Split can be found in the Proxy Statement and on the Company's Investor Relations website at https://investors.generationbio.com.

**About Generation Bio**

Generation Bio is a biotechnology company working to change what's possible for people living with T cell-driven autoimmune diseases. The Company is developing redosable therapeutics that reprogram T cells *in vivo* to reduce or eliminate the production and persistence of autoreactive T cells, which erroneously recognize and attack the body's own tissues, causing autoimmune diseases. Generation Bio's innovative approach leverages cell-targeted

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lipid nanoparticles (ctLNP) to selectively deliver small interfering RNA (siRNA) to T cells. This combination of selective delivery and an intracellular, genetically precise mechanism of target engagement could unlock a series of high-value, historically undruggable disease-driving genes in autoimmunity. For more information, please visit www.generationbio.com.

**Forward-Looking Statements**

Any statements in this press release about future expectations, plans and prospects for the Company, including statements about the Reverse Stock Split and the timing thereof; the impact of the Reverse Stock Split on stockholders; the potential impact of the Reverse Stock Split on the Company's share price; the potential for the Company to regain compliance with the minimum bid price requirement for continued listing on the Nasdaq Global Select Market; and other statements containing the words "believes," "anticipates," "plans," "expects," and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: uncertainties inherent in the identification and development of product candidates, including the anticipated timing of identification of the Company's product candidates, the conduct of research activities, the initiation and completion of preclinical studies and clinical trials and clinical development of the Company's product candidates; uncertainties as to the availability and timing of results from preclinical studies and clinical trials; uncertainties regarding the Company's novel technologies; whether results from preclinical studies will be predictive of the results of later preclinical studies and clinical trials; uncertainties regarding the anticipated timing of the submission of an investigational new drug application; whether the Company's cash resources are sufficient to fund the Company's operating expenses and capital expenditure requirements for the period anticipated; as well as the other risks and uncertainties set forth in the "Risk Factors" section of the Company's most recent annual report on Form 10-K and quarterly report on Form 10-Q, which are on file with the Securities and Exchange Commission, and in subsequent filings the Company may make with the Securities and Exchange Commission. In addition, the forward-looking statements included in this press release represent the Company's views as of the date hereof. The Company anticipates that subsequent events and developments will cause the Company's views to change. However, while the Company may elect to update these forward-looking statements at some point in the future, the Company specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing the Company's views as of any date subsequent to the date on which they were made.

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| |
|:---|
| **Investors and Media Contact** |
| Maren Killackey |
| Generation Bio |
| mkillackey@generationbio.com |
| 857-371-4638 |

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