On June 11th, the Supreme Court granted certiorari to consider whether, in a case alleging a violation of Rule 10b-5, the district court must require proof that the alleged misrepresentation or omission was material before certifying a plaintiff class based on the fraud-on-the-market theory, and whether, in such a case, the district court must allow the defendant to present evidence rebutting the applicability of the fraud-on-the-market theory before certifying the class. Question Presented. In the opinion below, the Ninth Circuit, joining the Third and Seventh Circuits, held that while plaintiffs must show that the security in question was traded in an efficient market and that the alleged misrepresentations were public, they need to only plausibly allege, but need not prove, that the claimed misrepresentations were material. View Ninth Circuit Opinion.