On November 6, 2017, the Second Circuit clarified that plaintiffs do not need to provide an “event study” to demonstrate market efficiency at the class certification stage in putative class actions. Rather, courts will certify a putative class if plaintiffs can demonstrate sufficient indirect evidence of market efficiency. Waggoner v. Barclays PLC, No. 16-1912-cv (2d. Cir. Nov 6, 2017).