Editing Efficient-market hypothesis (section)

== Efficient markets applied in securities class action litigation ==

The theory of efficient markets has been practically applied in the field of [[Securities Class Action]] Litigation. Efficient market theory, in conjunction with "[[fraud-on-the-market theory]]", has been used in [[Securities Class Action]] Litigation to both justify and as mechanism for the calculation of damages.<ref>{{cite news|url=https://www.nytimes.com/2014/06/29/your-money/are-markets-efficient-even-the-supreme-court-is-weighing-in.html|title=Are Markets Efficient? Even the Supreme Court Is Weighing In|first=Jeff|last=Sommer|date=28 June 2014|newspaper=The New York Times}}</ref> In the Supreme Court Case, [[Erica P. John Fund, Inc. v. Halliburton Co.|Halliburton v. Erica P. John Fund, U.S. Supreme Court, No. 13-317]], the use of efficient market theory in supporting securities class action litigation was affirmed. Supreme Court Justice Roberts wrote that "the court's ruling was consistent with the ruling in '[[Basic Inc. v. Levinson|Basic]]' because it allows '[[direct evidence]] when such evidence is available' instead of relying exclusively on the efficient markets theory."<ref>{{cite news|url=https://www.nytimes.com/2014/06/24/business/Justices-rule-on-class-actions-for-securities-fraud.html|title=New Hurdle in Investors' Class Actions|first=Adam|last=Liptak|date=23 June 2014|newspaper=The New York Times}}</ref>