GOSS Investor Alert: Gossamer Bio Securities Fraud Lawsuit - Investors With Losses May Seek to Lead the Class Action After CEO Allegedly Concealed PROSERA Placebo Risk: SueWallSt

Important Information Regarding Section 20(a) Individual Liability Claims

NEW YORK, May 7, 2026 /PRNewswire/ -- SueWallSt alerts investors in Gossamer Bio, Inc. (NASDAQ: GOSS) of a pending securities class action naming senior leadership as individual defendants. Class Period: June 16, 2025 through February 20, 2026. Find out if you qualify to recover losses or contact Joseph E. Levi, Esq. at [email protected] | (888) SueWallSt.

Gossamer shares collapsed over 80%, falling $1.71 per share from $2.13 to $0.42 on February 23, 2026, after the Company revealed its Phase 3 PROSERA study failed to meet the primary endpoint. The Court has set June 1, 2026 as the deadline to apply for lead plaintiff appointment.

The Named Individual Defendant

Faheem Hasnain, Gossamer's Chief Executive Officer, Chairman, and Co-founder, is named as an individual defendant in the securities class action filed in the United States District Court for the Southern District of California. As the Company's top executive throughout the Class Period, the lawsuit contends Hasnain possessed the power and authority to control the contents of Gossamer's SEC filings, press releases, and presentations to analysts and institutional investors.

Section 20(a) Control Person Framework

The complaint asserts claims under Section 20(a) of the Securities Exchange Act of 1934 (15 U.S.C. § 78t(a)), which establishes personal liability for individuals who exercise control over entities that violate Section 10(b) and Rule 10b-5. The action alleges that Hasnain:

• Controlled the substance and timing of Gossamer's public communications regarding the Phase 3 PROSERA study's trial design and patient enrollment
• Received copies of the Company's reports and press releases prior to issuance and had the ability and opportunity to prevent their release or cause corrections
• Had access to material non-public information concerning clinical site selection and protocol design issues at Latin American testing sites
• Knew or recklessly disregarded that positive representations about PROSERA's patient selection goals were materially false or misleading

Sarbanes-Oxley Certification Obligations

As CEO, Hasnain bore personal certification responsibilities under Sections 302 and 906 of the Sarbanes-Oxley Act, requiring him to certify the accuracy and completeness of the Company's periodic SEC filings. The pleading asserts that these certifications were made while Hasnain knew or was deliberately reckless in not knowing that Gossamer's public statements concealed material trial design risks.

Speak with an attorney about your recovery options or call (888) SueWallSt.

"Corporate officers have a duty to ensure their companies' public statements are accurate and complete. When a CEO personally oversees communications about a pivotal clinical trial while allegedly concealing protocol design risks that jeopardize the primary endpoint, Section 20(a) provides an important avenue for investor accountability." -- Joseph E. Levi, Esq.

Scienter Allegations Against the Individual Defendant

As averred in the complaint, Hasnain had actual knowledge of, or access to, non-public information concerning the PROSERA trial design and clinical test site selection. As the drug sponsor's top executive, he allegedly knew or recklessly disregarded the protocol design issues that ultimately caused the Phase 3 study to fail its primary endpoint of improved six-minute walk distance at Week 24.

Submit your information to join the recovery or contact Joseph E. Levi, Esq. at (888) SueWallSt.

WHY SUEWALLST -- Ranked in ISS Securities Class Action Services' Top 50 Report for seven consecutive years, SueWallSt is a nationally recognized leader in shareholder rights litigation. With a team of over 70 professionals, the firm has recovered hundreds of millions of dollars for investors.

Frequently Asked Questions About the GOSS Lawsuit

Q: Who are the defendants named in the GOSS lawsuit? A: The complaint names Gossamer Bio, Inc. and individual defendant Faheem Hasnain, CEO, Chairman, and Co-founder, who signed SEC filings and made public statements throughout the Class Period.

Q: What is the GOSS lead plaintiff deadline? A: The deadline to apply for lead plaintiff appointment is June 1, 2026. This deadline applies only to investors seeking to serve as lead plaintiff. Class members who do not apply may still participate in any recovery without taking action before this date.

Q: What does it cost me to participate? A: Nothing. Securities class actions are handled on a pure contingency basis. No upfront fees, no retainer, no out-of-pocket costs.

Q: What do GOSS investors need to do right now? A: Gather brokerage records including purchase dates, share quantities, and prices paid. Contact SueWallSt for a free, no-obligation evaluation at [email protected] or (888) SueWallSt. No immediate action is required to remain eligible as a class member.

Q: What if I already sold my GOSS shares -- can I still recover losses? A: Yes. Eligibility is based on when you purchased, not whether you still hold them. Investors who bought during the Class Period and sold at a loss may still participate.

Q: Do I need to go to court or give testimony? A: No. The overwhelming majority of class members never appear in court or give depositions. You submit a claim form to receive your portion of recovery.

CONTACT:
SueWallSt
Joseph E. Levi, Esq.
Ed Korsinsky, Esq.
33 Whitehall Street, 27th Floor
New York, NY 10004
[email protected]
Tel: (888) SueWallSt
Fax: (212) 363-7171

SOURCE SueWallSt.com