By J.B. Heaton (July 11, 2017, 2:32 PM EDT) -- On July 7, 2017, the U.S. Court of Appeals for the Second Circuit issued its opinion in the securities case of In re Petrobras Securities, No. 16-1914-CV, (2d Cir. July 7, 2017). The panel, including circuit Judges Peter Hall and Debra Ann Livingston, as well as Eastern District of New York District Judge Nicholas Garaufis sitting by designation, affirmed in part and vacated in part certain decisions by Southern District of New York Judge Jed Rakoff certifying a class of Petrobras securities litigants. In the part of the decision that affirmed the lower court, the Second Circuit found no abuse of discretion in Judge Rakoff's refusal to give statistical "event study" evidence a determinative role in deciding whether the Petrobras plaintiffs were entitled to the presumption of reliance that fraud-on-the-market theory allows for securities trades in efficient markets....