The Effect of Regulation Changes on Insider Trading

Abstract

Though lawyers and economists have speculated about the consequences of effective insider regulation, empirical research has yet to establish whether the regulation of insiders is even effective. Following the Securities and Exchange Act of 1933-1934, the most significant changes in insider regulation have occurred through a few important decisions in case law. This study examines the changes in the volume and profitability of insider trading after each of three important legal decisions concerning insiders. No. significant change in the properties of insider trading was observed following any of these three events. In addition, there appeared to be no combined effect from the three decisions. Thus it is concluded that the null hypothesis that changes in regulation had no effect on the trading of insiders cannot be rejected.