Risk and return: The case of merging firms

This study examines the market for acquisitions and the impact of mergers on the returns to the stockholders of the constituent firms. While employing the two-factor market model as recently developed and applied by Black-Jensen-Scholes and Fama-MacBeth, this study also considers changes in risk in analyzing the impact of mergers on stock prices. The results of the study are consistent with the hypothesis that the market for acquisitions is perfectly competitive and with the hypothesis that information regarding mergers is efficiently incorporated in the stock prices. Stockholders of acquiring firms seem to earn normal returns from mergers as from other investment-production activities with commensurate risk levels. Stockholders of acquired firms earn abnormal returns of approximately 14%, on the average, in the seven months preceding the merger.