The securities class action industry was launched a quarter-century ago when the Supreme Court recognized the so-called “fraud-on-the-market” presumption of reliance in most putative securities class actions. The result has been that—despite Congressional efforts at securities litigation reform—most securities class actions that survive the pleadings stage are likely to achieve class certification, forcing defendants to settle. In the meantime, as explained in prior blog posts, the best economic thinking has shifted, calling the empirical assumptions underlying the fraud-on-the-market presumption into question.
In Halliburton Co. v. Erica P. John Fund, Inc. (pdf), decided today, the Supreme Court declined to abandon that presumption, instead largely maintaining the status quo. The Court did clarify one key aspect of how class certification works in the securities context, holding that defendants are now entitled to attempt to rebut the presumption by introducing evidence at the class certification stage that there was no “price impact”—i.e., that misrepresentation alleged in a particular lawsuit did not affect the stock’s price. This adjustment will make it possible for defendants to challenge class certification in a number of securities class actions, but is unlikely to alter the landscape of securities litigation significantly—a result that is troubling from a policy perspective because (for reasons we have previously stated) securities class actions generally benefit the lawyers who bring and defend them rather than the investors.
We provide more details about the decision below.