After Halliburton: event studies and their role in federal securities fraud litigation

  • Event studies have become increasingly important in securities fraud litigation after the Supreme Court’s decision in Halliburton II. Litigants have used event study methodology, which empirically analyzes the relationship between the disclosure of corporate information and the issuer’s stock price, to provide evidence in the evaluation of key elements of federal securities fraud, including materiality, reliance, causation, and damages. As the use of event studies grows and they increasingly serve a gatekeeping function in determining whether litigation will proceed beyond a preliminary stage, it will be critical for courts to use them correctly. This Article explores an array of considerations related to the use of event studies in securities fraud litigation. It starts by describing the basic function of the event study: to determine whether a highly unusual price movement has occurred and the traditional statistical approach to making that determination. The Article goes on to identify special features of securities fraud litigation that distinguish litigation from the scholarly context in which event studies were developed. The Article highlights the fact that the standard approach can lead to the wrong conclusion and describes the adjustments necessary to address the litigation context. We use the example of six dates in the Halliburton litigation to illustrate these points. Finally, the Article highlights the limitations of event studies – what they can and cannot prove – and explains how those limitations relate to the legal issues for which they are introduced. These limitations bear upon important normative questions about the role event studies should play in securities fraud litigation.

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Metadaten
Author:Jill E. Fisch, Jonah B. Gelbach, Jonathan Klick
URN:urn:nbn:de:hebis:30:3-420669
URL:https://ssrn.com/abstract=2865815
DOI:https://doi.org/10.2139/ssrn.2865815
Parent Title (English):Center for Financial Studies (Frankfurt am Main): CFS working paper series ; No. 552
Series (Serial Number):CFS working paper series (552)
Publisher:Center for Financial Studies
Place of publication:Frankfurt, M.
Document Type:Working Paper
Language:English
Date of Publication (online):2016/11/15
Year of first Publication:2016
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2016/11/15
Issue:August 1, 2016
Page Number:85
HeBIS-PPN:396765432
Institutes:Wirtschaftswissenschaften / Wirtschaftswissenschaften
Wissenschaftliche Zentren und koordinierte Programme / Center for Financial Studies (CFS)
Dewey Decimal Classification:3 Sozialwissenschaften / 33 Wirtschaft / 330 Wirtschaft
Sammlungen:Universitätspublikationen
Licence (German):License LogoDeutsches Urheberrecht