Today, in Amgen Inc. v. Connecticut Retirement Plans and Trust Funds, No. 11-1085, the Supreme Court held that proof of materiality is not a prerequisite for class certification in a securities fraud class action under Section 10(b), even though materiality is a predicate of the fraud-on-the-market presumption of reliance.  The opinion for the majority of the Court was authored by Justice Ginsburg.  Justices Scalia, Thomas, and Kennedy dissented.  Justice Alito wrote a concurring opinion indicating that, in an appropriate case, he (like the three dissenting justices) would be open to reconsidering the fraud-on-the-market presumption.  For more, see our report on the decision.  (See also our report and article on the argument.)