In its long-awaited decision in Halliburton Co. v. Erica P. John Fund, Inc. (“Halliburton II”), the US Supreme Court upheld the validity of the fraud-on-the-market presumption set forth in Basic Inc. v. Levinson, 485 US 224 (1988), while clarifying that a defendant in a securities fraud class action must be permitted to rebut Basic’s presumption of reliance at the class certification stage with evidence that alleged misrepresentations had no price impact at the time of investment. This ruling confirms the existence of an important defense against class certification in federal securities fraud class actions and raises significant new questions for consideration by the lower courts.

View full memo, Supreme Court Preserves “Fraud-on-the-Market” and Validates Use of “Price Impact” Defense Against Class Certification in Securities Class Actions