In re FibroGen Inc. Securities Litigation


Defendants win at the class certification stage in this 10b-5 securities matter.

The plaintiff alleged that FibroGen, a biopharmaceutical company, misrepresented both the safety and efficacy data of its flagship drug, as well as the extent to which the FDA had approved the company’s protocol for testing the drug’s safety.

Defense counsel retained Paul Zurek of Cornerstone Research as an expert witness. Dr. Zurek filed a class certification report in which he opined that the alleged misrepresentations did not impact the company’s stock price during last three months of the alleged class period. Dr. Zurek showed that after the penultimate alleged corrective disclosure the remaining information allegedly concealed entered the public domain prior to the final alleged corrective disclosure and did not impact the stock price.

In his ruling, a Northern District of California judge denied class certification for the period analyzed by Dr. Zurek.  The matter settled soon after the judge’s ruling.

For more information, contact Sasha Aganin, Kristin Feitzinger, or Samer Semaan.

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Paul Zurek

Vice President,
Cornerstone Research;
Lecturer in Law,
Stanford Law School