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 announced the final results of its exchange offer for its 5.00% Convertible Senior Notes due 2027. Holders tendered $181,052,000 in aggregate principal amount of these notes, leaving $18,948,000 outstanding after the transaction.
Tendering holders received a pro rata mix of up to $72.0 million of new 7.50% Convertible Senior Secured First Lien Notes due 2030, up to 317,647,058 common shares or prefunded warrants, and, for early tendering eligible holders, additional warrants. Following early settlement on June 4, 2026, Gossamer entered into a supplemental indenture that eliminated substantially all restrictive covenants and certain events of default in the prior indenture for the exchanged notes.
D. E. Shaw and related entities report a large stake in Gossamer Bio, Inc. following a debt-for-equity exchange. They report beneficial ownership of 46,485,295 common shares, equal to 9.5% of Gossamer’s outstanding stock as of June 5, 2026, held through Valence, Cogence and funds managed by DESIM.
On June 4, 2026, the reporting group acquired 48,107,644 new shares plus new 7.50% Convertible Senior Secured First Lien Notes due 2030 and purchase warrants in an exchange of existing 5.00% convertible notes. In total, the issuer issued $65,174,000 of new convertible notes, 254,150,441 new shares, 33,402,727 prefunded warrants and 135,789,000 purchase warrants in the early settlement.
The new notes pay 7.50% interest, mature in 2030 with a springing 2027 maturity if more than $4.0 million of old notes remain, and include conversion features subject to stockholder approval and a 4.99%–9.99% beneficial ownership cap. The purchase warrants are exercisable from December 3, 2026 to June 4, 2031 with similar ownership limits. D. E. Shaw’s entities also hold short positions referencing 3,732,304 shares.
Gossamer Bio, Inc. reporting persons filed a joint Schedule 13G disclosing shared beneficial ownership positions in the issuer's Common Stock. The filing shows 37,665,073 shares reported for DeepCurrents/related parties (representing 7.7%) and 27,646,139 shares attributed to DCIG Capital Master Fund (representing 5.7%). The filing cites June 5, 2026 as the reference date for 488,846,722 shares outstanding used to calculate percentages.
The statement clarifies record ownership: the Fund and a separately managed account are direct owners, DeepCurrents is the investment manager, DCIG GP is the general partner, and Kai Zheng is a managing member. Each Reporting Person disclaims beneficial ownership of shares held directly by the others.
683 Capital Management, 683 Capital Partners and Ari Zweiman report beneficial ownership totaling 49,868,571 shares of Gossamer Bio. The figure includes 39,504,484 shares of Common Stock, 9,102,055 currently exercisable warrants, and 1,262,032 shares issuable upon conversion of convertible notes.
The filing states this position represents approximately 9.99% of Common Stock on a basis that uses 488,846,722 shares outstanding as of June 5, 2026 plus the currently exercisable warrants and specified convertible-note issuances; the calculation is subject to a 9.99% beneficial ownership limitation in the relevant indenture.
Gossamer Bio has called a virtual special stockholder meeting to approve several major capital structure changes tied to a recent exchange of its $200.0 million 5.00% convertible notes.
The company has already exchanged $181,052,000 of these notes (90.526%) for $65,174,000 of new 7.50% secured convertible notes due 2030, 254,150,441 new shares, 33,402,727 prefunded warrants and 135,789,000 purchase warrants, leaving $18,948,000 of old notes outstanding.
Stockholders are being asked to approve potential share issuances on conversion of up to $72.0 million of new notes and exercise of 135,789,000 purchase warrants (exceeding Nasdaq’s 20% dilution threshold), a large increase in authorized common shares from 700,000,000 to 4,000,000,000, an expanded equity incentive plan, authority for a reverse stock split, and the ability to adjourn the meeting if needed. The company discloses that these transactions have already caused substantial dilution and could ultimately give former noteholders up to 868,235,293 shares, or approximately 78.7% of outstanding common stock under full conversion assumptions.
Gossamer Bio disclosed that Context Capital Management and related reporting persons collectively hold 48,835,788 shares of common stock, representing 9.9% of the class. The filing states the percentage is calculated using 488,846,722 shares outstanding as of June 5, 2026. The report clarifies the ownership cap in an agreement is 9.99% and shows shared voting and dispositive power over the reported shares.
Gossamer Bio, Inc. director John D. Quisel received a grant of stock options covering 115,000 shares of common stock as board compensation. The options have an exercise price of $0.178 per share and expire on June 3, 2036.
The entire option grant becomes fully vested and exercisable on the earlier of the first anniversary of the grant date or the next annual meeting of stockholders, conditioned on his continued board service. This is a routine non-employee director award rather than an open-market share purchase or sale.
Gossamer Bio director Skye Drynan received a new stock option grant as part of board compensation. The award covers 115,000 options to buy Gossamer Bio common stock at an exercise price of $0.178 per share, expiring on June 3, 2036.
The option was granted under the company’s Non-Employee Director Compensation Program and represents 115,000 underlying shares following this transaction. All option shares vest and become exercisable on the earlier of the first anniversary of the grant date or the next annual stockholder meeting, assuming continued board service through that date.
Gossamer Bio, Inc. director Daniel Thomas O received a stock option award for 115,000 shares of common stock. The option has a per-share exercise price of $0.1780 and expires on June 3, 2036. This grant was made under the company’s Non-Employee Director Compensation Program and represents compensation rather than an open-market purchase.
The entire option becomes fully vested and exercisable on the earlier of the first anniversary of the grant date or the next annual meeting of stockholders, provided he continues serving on the board through that vesting date. Following this grant, he holds 115,000 stock options directly.
Gossamer Bio, Inc. director Russell J. Cox received a grant of stock options covering 115,000 shares of common stock at an exercise price of $0.178 per share. The award was made under the company’s Non-Employee Director Compensation Program.
The options become fully vested and exercisable on the earlier of the first anniversary of the grant date or the next annual meeting of stockholders, subject to his continued service on the board through that date. Following this grant, Cox holds stock options for 115,000 shares.