In recent years, several studies have begun to question the empirical va-lidity of this image. Eisenberg ~1976!, Demsetz ~1983!, Demsetz and Lehn ~1985!, Shleifer and Vishny ~1986!, and Morck, Shleifer and Vishny ~1988! show that, even among the largest American firms, there is a modest con-centration of ownership. Holderness and Sheehan ~1988! have found in the United States several hundred publicly traded firms with majority ~greater