Gossamer Bio, Inc. Class Action Lawsuit
Company: Gossamer Bio, Inc.
Ticker: (NASDAQ) GOSS
Class Action Period: June 16, 2025 - February 20, 2026
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Join the Gossamer Bio, Inc. Class Action Lawsuit
CLASS ACTION PERIOD
June 16, 2025 - February 20, 2026
Allegations
According to the complaint, defendants provided 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. On February 23, 2026, Gossamer published a press release and hosted a Special Call announcing topline results for its Phase 3 PROSERA study, which failed to meet the primary endpoint of improved six-minute walk distance (6MWD) at Week 24, with a +13.3 meter placebo-adjusted gain (p-0.0320) failing to meet the required 0.025 alpha threshold. Gossamer attributed this miss to patients at Latin American sites performing particularly well on placebo due to enrollment of a heavily-treated lower-risk population. Following this news, the price of Gossamer’s common stock declined from a closing market price of $2.13 per share on February 20, 2026 to $0.42 per share on February 23, 2025, a decline of over 80% in the span of just a single day.
Eligibility
To join the lawsuit, you must have experienced a loss on Gossamer Bio, Inc. shares purchased within the class period specified above.
Lead Plaintiff Deadline
If you suffered a loss in Gossamer Bio, Inc. during the relevant time frame, you have until June 1, 2026 to request that the Court appoint you as lead plaintiff. Your ability to share in any recovery doesn't require that you serve as a lead plaintiff.
Frequently Asked Questions
- How do I join the lawsuit against Gossamer Bio, Inc. (NASDAQ: GOSS)?
Investors who purchased shares of Gossamer Bio, Inc. (NASDAQ: GOSS) during the class period (June 16, 2025 - February 20, 2026) can join by submitting their transaction details through this case page.
- Ensure your purchase falls within the class period
- Provide basic transaction and loss details
- Submit your information before the deadline
The lead plaintiff deadline for this case is June 1, 2026, so investors should act quickly to protect their rights.
- Who is eligible for the Gossamer Bio, Inc. lawsuit?
Anyone who bought shares of Gossamer Bio, Inc. (NASDAQ: GOSS) during June 16, 2025 - February 20, 2026 and suffered financial losses may qualify.
- What is the lead plaintiff deadline to join the Gossamer Bio, Inc. case?
The lead plaintiff deadline for the Gossamer Bio, Inc. lawsuit is June 1, 2026. Investors should act quickly to avoid missing this deadline.
- What is the class period for Gossamer Bio, Inc.?
The class period for Gossamer Bio, Inc. (NASDAQ: GOSS) is June 16, 2025 - February 20, 2026, during which investors may have been affected by alleged misconduct.
- Can I still join the Gossamer Bio, Inc. lawsuit if I sold my shares?
Yes. Investors who purchased Gossamer Bio, Inc. shares during June 16, 2025 - February 20, 2026 may still qualify, even if they sold their shares later.
- How much compensation can I receive from the Gossamer Bio, Inc. lawsuit?
Compensation depends on the total losses and the final settlement. Eligible investors in the Gossamer Bio, Inc. case may receive a portion of the recovery.
- Do I need to pay to participate in the Gossamer Bio, Inc. case?
No, most securities fraud cases involving Gossamer Bio, Inc. operate on a contingency basis, meaning there are no upfront costs unless there is a recovery.
- Will I need to appear in court for the Gossamer Bio, Inc. lawsuit?
In most cases, investors do not need to appear in court. The legal team manages the Gossamer Bio, Inc. case on behalf of participants.
- What documents are required for the Gossamer Bio, Inc. lawsuit?
To participate in the Gossamer Bio, Inc. lawsuit, investors may need to provide transaction records, purchase dates, number of shares, and loss details.
- What happens after I submit my trade information for Gossamer Bio, Inc.?
After submission, your details for the Gossamer Bio, Inc. case will be reviewed, and you may be contacted regarding eligibility or next steps.
- Is this legal advice for the Gossamer Bio, Inc. lawsuit?
No, this page provides information about the Gossamer Bio, Inc. case and does not constitute legal advice or create an attorney-client relationship.
- Why should I act quickly on the Gossamer Bio, Inc. case?
The lead plaintiff deadline for the Gossamer Bio, Inc. lawsuit is June 1, 2026. If you are an investor, you may have the opportunity to seek appointment as lead plaintiff or remain an absent class member.
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