This paper studies the net effects of the long-run sequence of events leading to merger, and of merger per se, on shareholder wealth. The appropriate measure of the wealth effect is shown to be the abnormal dollar return cumulated over time. Using this measure, the long-run wealth effect of the event sequence culminating in merger is significantly negative for acquiring firms. For acquired firms, the effect is negative, but not significant. The immediate impact of merger per se is positive and highly significant for acquired firms but larger in absolute value, and negative for acquiring firms. The evidence also reveals that measured abnormal rates of return to acquiring firms are sensitive to a slight variation in model specification and dependent on firm size, with smaller firms earning significantly negative post-merger returns.

Ross's Arbitrage Pricing Theory (APT) is a tractible and reasonable alternative to the mean-variance model. Nonetheless, understanding of the theory has been obscured by the complexity of the sequence economy models used for motivation. By contrast, we give a simple and direct derivation of the APT in a finite economy. Using an explicit bound on the deviations from APT prices across assets, a coarse calculation shows that theoretical deviations from APT pricing are negligible in our economy.

This paper tests the hypothesis that the future distribution of payoffs provided by a common stock depends upon whether ownership of the stock also conveys control over the firm's activities. For 26 firms that had two classes of common stock outstanding, the class with superior voting rights traded at a premium relative to the other class. However, in four firms where the ownership structure of the firm also included a class of voting preferred stock, the class of common with superior voting rights traded at a significant discount relative to the class of common with inferior voting rights. The analysis suggests that there are both benefits and costs of corporate control.