 This distinguished between the primary liability of violators of Rule 10b-5 and non-primary defendants, who had not directly deceived investors.This was a more literal reading than hitherto of Section 10(b) of the Securities Exchange Act of 1934 and the Securities and Exchange Commission’s Rule 10b-5, which prohibit fraud or deceit in connection with the purchase or sale of securities.The Supreme Court's ruling reversed a long history of court decisions and SEC enforcement actions where aiders and abettors, often banks, accountants, trustees, and attorneys, were found liable under Rule 10b-5.