Securities Law Commons^™

Power And Statistical Significance In Securities Fraud Litigation, Jill E. Fisch, Jonah B. Gelbach

All Faculty Scholarship

Event studies, a half-century-old approach to measuring the effect of events on stock prices, are now ubiquitous in securities fraud litigation. In determining whether the event study demonstrates a price effect, expert witnesses typically base their conclusion on whether the results are statistically significant at the 95% confidence level, a threshold that is drawn from the academic literature. As a positive matter, this represents a disconnect with legal standards of proof. As a normative matter, it may reduce enforcement of fraud claims because litigation event studies typically involve quite low statistical power even for large-scale frauds.

This paper, written for …

Private Company Lies, Elizabeth Pollman

All Faculty Scholarship

Rule 10b-5’s antifraud catch-all is one of the most consequential pieces of American administrative law and most highly developed areas of judicially-created federal law. Although the rule broadly prohibits securities fraud in both public and private company stock, the vast majority of jurisprudence, and the voluminous academic literature that accompanies it, has developed through a public company lens.

This Article illuminates how the explosive growth of private markets has left huge portions of U.S. capital markets with relatively light securities fraud scrutiny and enforcement. Some of the largest private companies by valuation grow in an environment of extreme information asymmetry …

Federal Securities Fraud Litigation As A Lawmaking Partnership, Jill E. Fisch

All Faculty Scholarship

In its most recent Halliburton II decision, the Supreme Court rejected an effort to overrule its prior decision in Basic Inc. v. Levinson. The Court reasoned that adherence to Basic was warranted by principles of stare decisis that operate with “special force” in the context of statutory interpretation. This Article offers an alternative justification for adhering to Basic—the collaboration between the Court and Congress that has led to the development of the private class action for federal securities fraud. The Article characterizes this collaboration as a lawmaking partnership and argues that such a partnership offers distinctive lawmaking advantages. …