Scienter has been a critical element of a claim based on Exchange Act Section 10(b) in an SEC enforcement action since the Supreme Court’s decision in Aaron v. SEC, 446 U.S. 680 (1980). It has also been a key element in private damage actions based on the cause of action implied under Section 10(b) and Rule 10b-5 since Ernst & Ernst v. Hochfelder, 425 U.S....