We derive conditions under which permitting manager “insiders” to trade on personal account increases the equilibrium level of output and the welfare of shareholders. These increases are produced by two effects of insider trading. First, insider trading impounds information about hidden...

Securities trading has generated some of the most sensational scandals in the popular business press. In one of the most publicized cases of insider trading, in the late 1980s Michael R. Milken and Ivan F. Boesky were sentenced to stiff prison terms and payment of enormous damage assessments and...