Welcome to our dedicated page for Gossamer Bio SEC filings (Ticker: GOSS), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Gossamer Bio filings document a clinical-stage biopharmaceutical issuer centered on seralutinib for PAH and PH-ILD. Form 8-K reports cover operating and financial results, Phase 3 PROSERA clinical disclosures, material agreements, unregistered equity issuances, resource-allocation actions, and Nasdaq listing-compliance notices involving its common stock.
Proxy materials describe board governance, shareholder voting matters, executive compensation, equity awards, and incentive-plan administration. The filing record also documents capital-structure matters and formal disclosures connected to a late-stage pulmonary hypertension development company.
Gossamer Bio, Inc. director Sandra Milligan received a grant of stock options covering 115,000 shares of common stock. The options have an exercise price of $0.178 per share and expire on June 3, 2036. The award was made under the company’s Non-Employee Director Compensation Program and becomes fully vested and exercisable on the earlier of the first anniversary of the grant date or the next annual meeting of stockholders, subject to her continued board service. Following this grant, she holds 115,000 stock options directly.
Gossamer Bio, Inc. director Nathan Steven D received a grant of stock options for 115,000 shares of common stock at an exercise price of $0.1780 per share. The options expire on June 3, 2036 and vest in full on the earlier of the first anniversary of the grant or the next annual stockholder meeting, subject to continued board service.
Gossamer Bio, Inc. completed the early settlement of its exchange offer for $181,052,000 aggregate principal of its 5.00% Convertible Senior Notes due 2027, representing 90.526% of the notes outstanding. In exchange, the company issued $65,174,000 of new 7.50% Convertible Senior Secured First Lien Notes due 2030, 254,150,441 new common shares, 33,402,727 prefunded warrants and 135,789,000 purchase warrants.
The new notes carry a 7.50% cash interest rate, mature on July 1, 2030, and include a springing maturity to March 2, 2027 if more than $4.0 million of old notes remain outstanding. They also include a monthly tested minimum liquidity covenant starting with the fiscal month ending June 30, 2026, initially set at $40 million with step-downs tied to equity raises and FDA new drug application milestones.
Conversion and warrant exercise into stock generally require future stockholder approval, and both the new notes and warrants have ownership limits to cap any single holder’s beneficial ownership. A supplemental indenture for the old notes removes most restrictive covenants, and tendering holders agreed to lock-up and voting commitments for the new shares through the special meeting record date.
Gossamer Bio, Inc. reported the results of its annual stockholder meeting. Stockholders re-elected Class II directors Faheem Hasnain and Russell Cox to three-year terms expiring at the 2029 annual meeting. Hasnain received 92,301,637 votes for and Cox received 88,975,980 votes for, with substantial broker non-votes recorded for each.
Stockholders also ratified the selection of Ernst & Young LLP as independent registered public accounting firm for the fiscal year ending December 31, 2026, with 163,185,993 votes for. In an advisory vote, stockholders approved the compensation of the company’s named executive officers, with 111,286,550 votes for and 7,545,502 against.
Gossamer Bio reported that it has extended the early tender date for its ongoing exchange offer and consent solicitation for its 5.00% Convertible Senior Notes due 2027 to 5:00 p.m. New York City time on June 2, 2026. The exchange offer would swap these existing notes for a mix of up to $72.0 million in new 7.50% Convertible Senior Secured First Lien Notes due 2030, up to 317,647,058 shares of common stock or prefunded warrants, and, for holders who tender by the extended early tender date, additional purchase warrants. As of 5:00 p.m. on June 1, 2026, holders had validly tendered $181,052,000 in principal amount of the existing notes, toward a minimum condition that 98% of the notes be tendered. The expected early settlement date is June 4, 2026, with the final expiration scheduled for June 16, 2026 and a currently expected final settlement on June 18, 2026, if all conditions are satisfied or waived.
Gossamer Bio, Inc. is holding a virtual Special Meeting to approve proposals tied to an Exchange Offer to exchange $200.0 million of outstanding 5.00% Convertible Senior Notes due 2027 for a package of securities including up to $72.0 million of newly issued 7.50% first‑lien Convertible Senior Secured Notes due 2030 and up to 317,647,058 shares of common stock (or prefunded warrants), and, for early tenders, up to 150,000,000 purchase warrants.
The Exchange Offer, supported by holders representing approximately 75.2% of the Existing Convertible Notes, is expected to substantially dilute existing common stockholders: on a 100% tender and no prefunded warrants assumption, Existing Noteholders would hold ~57.5% of outstanding common stock immediately after closing and up to ~78.7% if the New Convertible Notes convert at the floor conversion price. The Board recommends voting FOR all proposals, which include increasing authorized shares from 700,000,000 to 4,000,000,000, approving the Restated 2019 Incentive Award Plan, Nasdaq Rule 5635(d) issuance authorization, and reverse split authority.
Gossamer Bio, Inc. is holding a virtual Special Meeting to approve proposals tied to an Exchange Offer to exchange $200.0 million of outstanding 5.00% Convertible Senior Notes due 2027 for a package of securities including up to $72.0 million of newly issued 7.50% first‑lien Convertible Senior Secured Notes due 2030 and up to 317,647,058 shares of common stock (or prefunded warrants), and, for early tenders, up to 150,000,000 purchase warrants.
The Exchange Offer, supported by holders representing approximately 75.2% of the Existing Convertible Notes, is expected to substantially dilute existing common stockholders: on a 100% tender and no prefunded warrants assumption, Existing Noteholders would hold ~57.5% of outstanding common stock immediately after closing and up to ~78.7% if the New Convertible Notes convert at the floor conversion price. The Board recommends voting FOR all proposals, which include increasing authorized shares from 700,000,000 to 4,000,000,000, approving the Restated 2019 Incentive Award Plan, Nasdaq Rule 5635(d) issuance authorization, and reverse split authority.
Gossamer Bio launched a major debt exchange and reported first-quarter 2026 results while advancing its lead PAH drug seralutinib toward a potential FDA filing. The company is offering to swap its $200 million 5.00% convertible notes due 2027 into a mix of new 7.50% secured convertible notes due 2030, up to 317.6 million shares or prefunded warrants, and up to 150 million purchase warrants, targeting at least 98% noteholder participation and backed by holders of about 75.2% of the notes. Management expects this could cut convertible debt outstanding to $72 million and extend maturities. Separately, Gossamer secured an in-person Pre-NDA Type B FDA meeting in mid-June and plans a September 2026 NDA submission for seralutinib in PAH, with potential approval in the third quarter of 2027. For the quarter ended March 31, 2026, revenue from its Chiesi collaboration was $17.0 million, R&D expenses were $43.1 million, G&A was $18.7 million, and net loss was $46.7 million on $99.2 million of cash, cash equivalents and marketable securities, which it expects to fund operations into the first quarter of 2027.
Gossamer Bio launched a major debt exchange and reported first-quarter 2026 results while advancing its lead PAH drug seralutinib toward a potential FDA filing. The company is offering to swap its $200 million 5.00% convertible notes due 2027 into a mix of new 7.50% secured convertible notes due 2030, up to 317.6 million shares or prefunded warrants, and up to 150 million purchase warrants, targeting at least 98% noteholder participation and backed by holders of about 75.2% of the notes. Management expects this could cut convertible debt outstanding to $72 million and extend maturities. Separately, Gossamer secured an in-person Pre-NDA Type B FDA meeting in mid-June and plans a September 2026 NDA submission for seralutinib in PAH, with potential approval in the third quarter of 2027. For the quarter ended March 31, 2026, revenue from its Chiesi collaboration was $17.0 million, R&D expenses were $43.1 million, G&A was $18.7 million, and net loss was $46.7 million on $99.2 million of cash, cash equivalents and marketable securities, which it expects to fund operations into the first quarter of 2027.
Gossamer Bio, Inc. reported first‑quarter 2026 revenue of $16.955 million, all from its collaboration with Chiesi, up from $9.889 million a year earlier. The company remains unprofitable, with a net loss of $46.664 million and an accumulated deficit of $1.4856 billion.
Cash, cash equivalents and marketable securities totaled about $99.2 million as of March 31, 2026, while total liabilities were $290.4 million, including $200 million of 5.00% convertible senior notes due 2027. Management states existing liquidity funds operations only into the first quarter of 2027 and raises substantial doubt about the company’s ability to continue as a going concern.
To cut expenses, Gossamer began a workforce reduction of 73 employees, roughly 46% of its staff, in March 2026, recording about $6.1 million in severance and related charges. The company continues to focus development on seralutinib for pulmonary arterial hypertension and PH‑ILD under its global collaboration with Chiesi.
Gossamer Bio, Inc. Schedule 13G/A reports that Octagon-related reporting persons beneficially own 8,976,054 common shares, representing 3.8% of the class. The filing states the calculation is based on 234,696,281 shares outstanding as of March 10, 2026, plus 1,226,504 shares issuable upon exercise of warrants.
The ownership position is reported as shared voting and dispositive power. The filing discloses that the position includes 7,750,000 directly held common shares and warrants to purchase up to 1,226,054 shares (exercise price $2.04, expiration July 24, 2028).