RARE Investors Have Opportunity to Lead Ultragenyx Pharmaceutical Inc. Securities Fraud Lawsuit

The Schall Law Firm reminds investors of a class action lawsuit against Ultragenyx Pharmaceutical Inc.

Published on Feb. 6, 2026

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The Schall Law Firm, a national shareholder rights litigation firm, is reminding investors of a class action lawsuit against Ultragenyx Pharmaceutical Inc. for violations of securities laws. Investors who purchased the company's securities between August 3, 2023 and December 26, 2025 are encouraged to contact the firm to participate in the lawsuit.

Why it matters

This lawsuit alleges that Ultragenyx made false and misleading statements to the market about its understanding of the effects of its drug candidate on patients with Osteogenesis Imperfecta (OI). The company's failures were revealed when its Phase III ORBIT study failed to achieve a statistically significant reduction in annualized fracture rate, contradicting the company's previous optimistic statements.

The details

The class action lawsuit alleges that Ultragenyx violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated by the U.S. Securities and Exchange Commission. Investors who purchased the company's securities during the class period from August 3, 2023 to December 26, 2025 are encouraged to contact the Schall Law Firm to participate in the lawsuit.

  • The class period for the lawsuit is from August 3, 2023 to December 26, 2025.
  • Investors have until April 6, 2026 to contact the Schall Law Firm to participate in the lawsuit.

The players

Ultragenyx Pharmaceutical Inc.

A biopharmaceutical company that develops therapies for rare and ultra-rare genetic diseases.

The Schall Law Firm

A national shareholder rights litigation firm that specializes in securities class action lawsuits and shareholder rights litigation.

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What they’re saying

“We also encourage you to contact Brian Schall of the Schall Law Firm, 2049 Century Park East, Suite 2460, Los Angeles, CA 90067, at 310-301-3335, to discuss your rights free of charge.”

— Brian Schall, Attorney, Schall Law Firm

What’s next

The judge in the case will decide on whether to certify the class by April 6, 2026.

The takeaway

This lawsuit highlights the importance of transparency and accurate disclosures by pharmaceutical companies, especially those developing treatments for rare and ultra-rare diseases. Investors who suffered losses due to Ultragenyx's alleged misrepresentations have an opportunity to seek recourse through this class action lawsuit.