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Gossamer Bio, Inc.

Securities Class Action

  • Date:
  • 6/1/2026
  • Company Name:
  • Gossamer Bio, Inc.
  • Stock Symbol:
  • GOSS
  • Class Period:
  • FROM 6/16/2025 TO 2/20/2026
  • Status:
  • Filed
  • Filing Date:
  • 3/31/2026
  • Court:
  • U.S. District Court: District of Southern California

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Bragar Eagel & Squire, P.C., a nationally recognized stockholder rights law firm, announces that a class action lawsuit has been filed against Gossamer Bio, Inc. (“Gossamer” or the “Company”) (NASDAQ:GOSS) in the United States District Court for the Southern District of California on behalf of all persons and entities who purchased or otherwise acquired Gossamer securities between June 16, 2025, and February 20, 2026, both dates inclusive (the “Class Period”). Investors have until June 1, 2026 to apply to the Court to be appointed as lead plaintiff in the lawsuit.

 

According to the complaint, during the class period, defendants provided investors with material information concerning Gossamer’s Phase 3 PROSERA study evaluating seralutinib for the treatment of pulmonary arterial hypertension (PAH). Defendants’ statements included, among other things, confidence in PROSERA’s trial design. Defendants provided these overwhelmingly positive statements to investors while, at the same time, disseminating false and misleading statements and/or concealing material adverse facts concerning the study design for the Company’s Phase 3 PROSERA study, particularly, controlling for the placebo response at the Latin American testing sites. This caused Plaintiff and other shareholders to purchase Gossamer’s securities at artificially inflated prices.

 

If you purchased or otherwise acquired Gossamer shares and suffered a loss, are a long-term stockholder, have information, would like to learn more about these claims, or have any questions concerning this announcement or your rights or interests with respect to these matters, please contact Brandon Walker or Melissa Fortunato by email at investigations@bespc.com, telephone at (212) 355-4648, or by filling out the form below.  There is no cost or obligation to you.
Contact Instructions
Please contact Brandon Walker or Melissa Fortunato by email at investigations@bespc.com with any questions.
The individual or institution below (“Plaintiff”) has reviewed and agrees to the Bragar Eagel & Squire, P.C. (“BESPC”) retainer agreement and authorizes BESPC to prosecute an action on Plaintiff’s behalf under the federal securities laws or applicable state laws to recover damages on behalf of investors in Gossamer Bio. BESPC will prosecute the action on a full contingency basis and will forward all costs and expenses.
 

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