{"url_path":"/sec/goss/8-k/2026-05-18/cover-page","section_key":"cover-page","section_title":"Cover Page","topic":"sec","document":{"doc_type":"8-K","doc_date":"2026-05-18","source_url":"https://www.sec.gov/Archives/edgar/data/1728117/0001728117-26-000036-index.html","accession_number":"0001728117-26-000036","cik":"0001728117","ticker":"GOSS","issuer_name":"Gossamer Bio, Inc.","edgar_url":"https://www.sec.gov/Archives/edgar/data/1728117/0001728117-26-000036-index.html","primary_entity_key":"0001728117","primary_entity_name":"Gossamer Bio, Inc."},"word_count":2547,"has_tables":true,"body_markdown":"goss-20260518\n0001728117FALSE00017281172026-05-182026-05-18\n\nUNITED STATES\n\nSECURITIES AND EXCHANGE COMMISSION\n\nWASHINGTON, D.C. 20549\n\nFORM 8-K\n\nCURRENT REPORT\n\nPursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934\n\nDate of Report (Date of earliest event reported): May 18, 2026\n\nGOSSAMER BIO, INC.\n\n(Exact name of Registrant as Specified in Its Charter)\n\n \n\nDelaware001-3879647-5461709\n\n(State or Other Jurisdiction\nof Incorporation)(Commission File Number)(IRS Employer\nIdentification No.)\n\n   \n\n3115 Merryfield Row, Suite 120\n\nSan Diego, California, 92121\n\n(Address of Principal Executive Offices) (Zip Code)\n\n(858) 684-1300\n\n(Registrant’s Telephone Number, Including Area Code)\n\nN/A\n\n(Former Name or Former Address, if Changed Since Last Report)\n\nCheck 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 Instructions A.2. below):\n\n☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)\n\n☒\nSoliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)\n\n☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))\n\n☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))\n\nSecurities registered pursuant to Section 12(b) of the Act:\n\nTitle of each class Trading\nSymbol(s) Name of each exchange on which registered\n\nCommon Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market\n\nIndicate 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).\n\nEmerging growth company ☐\n\nIf 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.  ☐\n\nExplanatory Note\n\nExchange Offer and Consent Solicitation\n\nOn May 18, 2026, Gossamer Bio, Inc. (the “Company”) commenced an exchange offer (the “Exchange Offer”) to exchange any and all of its 5.00% Convertible Senior Notes due 2027 (the “Existing Convertible Notes”) issued pursuant to an indenture, dated as of May 21, 2020, and a first supplemental indenture, dated as of May 21, 2020 (together, the “Existing Convertible Notes Indenture”), for a pro rata portion of (i) up to $72.0 million in aggregate principal amount of its new 7.50% Convertible Senior Secured First Lien Notes due 2030 (the “New Convertible Notes”), (ii) up to 317,647,058 shares of its common stock (the “Common Stock”), par value $0.0001 per share (the “New Shares”) or, in lieu of issuing shares of Common Stock to the extent any investor would beneficially own greater than 9.99% of the outstanding Common Stock, prefunded warrants to purchase shares of Common Stock (the “Prefunded Warrants” and, together with the New Shares, the “Equity Securities”) and (iii) up to 150,000,000 warrants to purchase shares of its Common Stock (the “Purchase Warrants”). Simultaneously with the Exchange Offer, the Company is soliciting consents (the “Consent Solicitation”) from holders of the Existing Convertible Notes to adopt certain proposed amendments (the “Proposed Amendments”) to the Existing Convertible Notes Indenture. The Proposed Amendments would eliminate substantially all of the restrictive covenants in the Existing Convertible Notes Indenture as well as certain events of default and related provisions applicable to the Existing Convertible Notes.\n\nPursuant to the terms of the Exchange Offer, if, at or prior to 5:00 p.m., New York City time, on June 1, 2026 (such time and date, as the same may be extended, the “Early Tender Date”), all conditions to the Exchange Offer and Consent Solicitation have been or are concurrently satisfied or waived, the Company may, subject to the terms of the Transaction Support Agreement (as defined below), accept for exchange (the “Early Settlement”) any Existing Convertible Notes validly tendered (and not validly withdrawn) at or prior to the Early Tender Date. The exchange for such Existing Convertible Notes would be made on the second business day following the Early Tender Date (the “Early Settlement Date”), which is currently expected to occur as early as June 3, 2026. Whether or not the Early Settlement occurs, if all conditions to the Exchange Offer and Consent Solicitation have been satisfied or waived at 5:00 p.m., New York City time, on June 16, 2026 (such time and date, as the same may be extended, the “Expiration Deadline”), unless extended, the Company will consummate the exchange of any Existing Convertible Notes that are validly tendered (and not validly withdrawn) at or prior to the Expiration Deadline on the second business day immediately following the Expiration Deadline (the “Final Settlement Date”), which is currently expected to occur on June 18, 2026. It is a condition to the Exchange Offer that a minimum of 98% of the aggregate principal amount of Existing Convertible Notes shall have been validly tendered (and, if applicable, not validly withdrawn). The Company’s ability to amend, extend, terminate, or waive the conditions of the Exchange Offer are subject to the terms of the Transaction Support Agreement.\n\nEligible Holders whose Existing Convertible Notes are accepted for exchange will also receive accrued and unpaid interest on such Existing Convertible Notes from, and including, the most recent interest payment date to, but excluding, the applicable Settlement Date, payable in cash on the applicable Settlement Date. Interest will cease to accrue on the applicable Settlement Date for all Existing Convertible Notes accepted for exchange in the Exchange Offer.\n\nUpon the terms and subject to the conditions of the Exchange Offer and Consent Solicitation, eligible holders of Existing Convertible Notes who validly tender (and do not validly withdraw) their Existing Convertible Notes and deliver their related consents at or prior to the Early Tender Date will be eligible to receive for each $1,000 in aggregate principal amount of Existing Convertible Notes validly tendered for exchange, $360 in aggregate principal amount of New Convertible Notes, 1,588.2353 shares of common stock (or Prefunded Warrants) and 750 Purchase Warrants. Eligible holders who validly tender Existing Convertible Notes after the Early Tender Date but at or prior to the Expiration Deadline, and whose Existing Convertible Notes are accepted for exchange by the Company, will receive for each $1,000 in aggregate principal amount of Existing Convertible Notes validly tendered for exchange, $360 in aggregate principal amount of New Convertible Notes and 1,588.2353 shares of common stock (or Prefunded Warrants).\n\nIf the Exchange Offer is consummated, the New Convertible Notes issued in the exchange will be secured, first lien obligations of the Company. The New Convertible Notes will mature on July 1, 2030, unless earlier redeemed, converted, equitized or repurchased in accordance with the terms of the New Convertible Notes, provided that the New Convertible Notes shall have a springing maturity date of March 2, 2027 (91 days prior to the stated maturity of the Existing Convertible Notes) if more than $4.0 million of the Existing Convertible Notes remain outstanding at such time. The New Convertible Notes will bear interest at a rate of 7.50% per annum from the initial settlement date of such New Convertible Notes, which interest will be payable in cash semi-annually on January 1 and July 1 of each year, starting on January 1, 2027.\n\nThe conversion rate for the New Convertible Notes will initially be the number of shares of Common Stock per $1,000 principal amount of New Convertible Notes equal to quotient of $1,000 divided by a 10% premium to the Reference Price, rounded to the nearest 1/10,000th of a share. The “Reference Price” will equal the greater of (i) $0.17 and (ii) the lower of (x) $0.34 and (y) the average of the daily volume-weighted average prices for the seven (7) consecutive VWAP trading days beginning on, and including, the VWAP trading day immediately following the final settlement date. The Purchase Warrants will be exercisable with a cash exercise price equal to the greater of (i) $0.34 and (ii) a 25% premium to the Reference Price, subject to adjustments.\n\nPrior to obtaining stockholder approval of certain proposals as described in more detail under “—Stockholder Proposals” below that will allow the issuance of common stock pursuant to the terms of the New Convertible Notes and Purchase Warrants, the Company will be permitted to satisfy its obligations upon conversion of the New Convertible Notes, and upon exercise of the Purchase Warrants, only in the form of cash settlement. Following such stockholder approval, the Company will be permitted to satisfy its obligations under the New Convertible Notes and Purchase Warrants with any settlement method it is otherwise permitted to elect, including by physical settlement of shares of common stock. Additionally, a holder of (i) New Convertible Notes will not be permitted to convert its New Convertible Notes at any time prior to the later of (a) the date the conversion rate has been determined and (b) the earlier of (1) the date of the Special Meeting at which we seek stockholder approval of the Stockholder Proposals, whether or not such approvals are obtained and (2) the date that is 61 calendar days following the initial settlement date of the Offered Securities, and (ii) Purchase Warrants will be exercisable at any time from December 3, 2026 until June 3, 2031. A “make whole” premium will be payable on the New Convertible Notes through an increase to the conversion rate in certain circumstances to compensate converting holders for interest that would have been payable to the maturity date.\n\nThe indenture that will govern the New Convertible Notes (the “New Convertible Notes Indenture”) will include incurrence based negative covenants, including but not limited to, limitations on debt, limitations on liens and entry into restrictive agreements, limitations on mergers, consolidations or sales of all or substantially all assets, limitations on transactions with affiliates, limitations on restricted payments and investments, limitations on disposals of assets, limitations on foreign subsidiaries and limitations on impairment of security. The New Convertible Notes Indenture will also include usual and customary affirmative covenants, including but not limited to, further assurance, payment of obligations, reporting, and compliance certificate. The New Convertible Notes Indenture will also contain a minimum liquidity covenant that will require us to maintain a minimum amount of liquidity of $40 million, tested monthly on the date that the compliance certificate for the applicable month will be delivered and commencing with the fiscal month ending June 30, 2026; provided that the minimum liquidity requirement will be reduced to (x) $20 million, upon completion of one or more equity raises with aggregate proceeds of at least $100 million, (y) $10 million, subject to satisfaction of condition (x) above and written notice from the FDA by December 1, 2026 that it has accepted for filing the Company’s new drug application and (z) $0, subject to satisfaction of conditions (x) and (y) above and completion of one or more equity raises with aggregate proceeds (including all proceeds under condition (x) above) of at least $150 million. The New Convertible Notes Indenture will contain other customary terms including with respect to events of default, amendments, defeasance, and satisfaction and discharge, and will be governed by New York law.\n\nUnder certain circumstances and subject to conditions set forth in the New Convertible Notes Indenture, the Company may elect to force a mandatory conversion of the New Convertible Notes.\n\nIf certain corporate events constituting a fundamental change occur (which shall include, among other things, the acquisition by any person or group of more than 50% of the outstanding common stock of the Company or a delisting of the Company’s common stock), the Company shall offer to repurchase all of the outstanding New Convertible Notes for cash at a repurchase price equal to 100% of the aggregate principal amount of the New Convertible Notes then outstanding plus accrued and unpaid interest.\n\nEstimated fees and expenses of approximately $7.2 million are expected to be paid in connection with the Exchange Offer and Consent Solicitation, assuming 100% participation in the Exchange Offer, of which approximately $0.3 million had been paid as of March 31, 2026.\n\nThe Offered Securities, and the Underlying Shares (as defined below) have not been, and will not be, registered under the Securities Act of 1933, as amended (the “Securities Act”), or any other securities laws. This Current Report on Form 8-K shall not constitute an offer to sell, or the solicitation of an offer to buy, the Offered Securities, the Underlying Shares, the Existing Convertible Notes or any other securities, nor will there be any sale of such securities or any other securities, in any state or other jurisdiction in which such offer, sale or solicitation would be unlawful.\n\nIrrevocable Election to Cash Settle Existing Convertible Notes\n\nPursuant to the terms of the Existing Convertible Notes Indenture, we are permitted by notice to the holders of Existing Convertible Notes, to elect to irrevocably fix the settlement method for the Existing Convertible Notes. On May 18, 2026, we provided notice to holders of Existing Convertible Notes of our irrevocable election to settle the Existing Convertible Notes exclusively in cash. Such election will apply to all conversions of Existing Convertible Notes with a conversion date that is on or after the date of such notice.\n\nStockholder Proposals\n\nIn connection with the transactions contemplated by the Exchange Offer and the Transaction Support Agreement, the Company will file a preliminary proxy statement with the Securities and Exchange Commission (the “SEC”) for the purposes of soliciting the affirmative vote of its stockholders at a special meeting of stockholders of the Company (the “Special Meeting”) with respect to the following proposals (the “Stockholder Proposals”):\n\n•To approve, in accordance with Nasdaq Listing Rule 5635(d), of the potential issuance of shares of Common Stock upon (i) conversion of up to $72.0 million in aggregate principal amount of the New Convertible Notes and make-whole payments in the form of Common Stock, and (ii) exercise of up to 150,000,000 Purchase Warrants, which issuances would, in the aggregate, exceed 20% of the shares of Common Stock issued and outstanding immediately prior to the time of commencement of the Exchange Offer;\n\n•To approve the Restated Plan to increase the number of shares of Common Stock authorized for issuance thereunder;\n\n•To approve an amendment to the Company’s Restated Certificate of Incorporation (the “Charter”) to increase the number of authorized shares of the Company’s Common Stock from 700,000,000 to 4,000,000,000, in order to support, among other things, the additional share issuances of Common Stock issuable upon conversion of the New Convertible Notes, Prefunded Warrants and Purchase Warrants and under the Restated Plan;\n\n•To approve a series of 30 alternate amendments to the Charter to effect (i) a reverse stock split of the Company’s issued and outstanding shares of Common Stock (on a range of proposed ratios of not less than 1-for-10 on the low end and not greater than 1-for-150 on the high end), with the exact ratio to be determined by the Board at a later date and (ii) a proportionate reduction in the number of authorized shares of Common Stock (and corresponding decrease to the total number of authorized shares of the Company’s capital stock); and\n\n•To approve one or more adjournments of the Special Meeting, if necessary, to solicit additional proxies if there are not sufficient votes to approve the foregoing proposals at the Special Meeting or any adjournment(s) thereof."}