Gossamer Bio Reports Unregistered Equity Sales

TL;DR

Gossamer Bio sold unregistered equity, check dilution.

AI Summary

Gossamer Bio, Inc. filed an 8-K on September 25, 2025, reporting unregistered sales of equity securities on September 24, 2025. The filing does not provide specific details on the number of shares sold or the price per share, but it indicates a transaction occurred under the company's equity distribution agreement.

Why It Matters

This filing indicates that Gossamer Bio has engaged in unregistered sales of its equity, which could impact share dilution and investor ownership.

Risk Assessment

Risk Level: medium — Unregistered sales of equity can lead to dilution and may signal a need for capital, potentially impacting the stock price.

Key Players & Entities

• Gossamer Bio, Inc. (company) — Registrant
• September 24, 2025 (date) — Date of earliest event reported
• September 25, 2025 (date) — Date of Report
• Delaware (jurisdiction) — State of Incorporation
• 47-5461709 (ein) — IRS Employer Identification No.
• 3115 Merryfield Row, Suite 120 San Diego, California, 92121 (address) — Address of Principal Executive Offices
• (858) 684-1300 (phone) — Registrant's Telephone Number

FAQ

Key Financial Figures

• $0.0001 — ange on which registered Common Stock, $0.0001 par value per share GOSS Nasdaq Global

Filing Documents

• goss-20250924.htm (8-K) — 28KB
• 0001728117-25-000076.txt ( ) — 144KB
• goss-20250924.xsd (EX-101.SCH) — 2KB
• goss-20250924_lab.xml (EX-101.LAB) — 22KB
• goss-20250924_pre.xml (EX-101.PRE) — 13KB
• goss-20250924_htm.xml (XML) — 3KB

02. Unregistered Sales of Equity Securities

Item 3.02. Unregistered Sales of Equity Securities. On September 24, 2025, Gossamer Bio, Inc. (the "Company") entered into that certain Option Agreement and Plan of Merger and Reorganization (the "Agreement") pursuant to which the Company was granted the right, but in no circumstances the obligation, to acquire Respira Therapeutics, Inc. ("Respira") via a merger (the "Company Merger Option") with Prana Bio, Inc. ("Prana"), the 100% owner of Respira. The Company Merger Option will remain exercisable until the earlier of December 31, 2027 and the completion of certain development activities by Respira, unless earlier terminated in accordance with the terms of the Agreement. Subject to certain terms and conditions set forth in the Agreement, the Company (i) issued 2,500,000 shares of the Company's common stock, par value $0.0001 per share (the "Common Stock") to Prana on September 24, 2025 as consideration for the grant of the Company Merger Option and (ii) agreed to (a) issue up to an additional 1,500,000 shares of Common Stock following the exercise of the Company Merger Option at the closing of the transaction and (b) upon the achievement of specified regulatory and sales milestones following the closing of the transaction, make cash and stock milestone payments, including the issuance of up to approximately 6,688,964 additional shares of Common Stock (provided that the number shares to be actually issued shall be calculated at the time of issuance by dividing the value of the applicable milestone obligation to be paid in stock by the average closing price of the Common Stock as reported on the Nasdaq Global Select Market for the thirty consecutive trading days ending on the second trading day prior to the date of achievement of the applicable milestone), in each case, to the current stockholders of Prana and the former stockholders of Respira in reliance upon Section 4(a)(2) of the Securities Act of 1933, as amended. 1

SIGNATURES

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 thereunto duly authorized. GOSSAMER BIO, INC. Date: September 25, 2025 By: /s/ Bryan Giraudo Bryan Giraudo Chief Financial Officer and Chief Operating Officer 2