Acquirer Valuation and Acquisition Decisions : Identifying Mispricing Using Short Interest

We use short interest as an investor-based measure of over/undervaluation that distinguishes between the misvaluation and Q-theories of mergers. Using this measure, we find that misvaluation is a strong determinant of merger decision making. Firms in the top quintile of short interest are 54% more likely to engage in stock acquisitions and 22% less likely to engage in cash acquisitions. Stock (but not cash) acquirers have higher short interest than their targets. Overall, our results suggest that the previously documented underperformance of stock acquirers and the overperformance of cash acquirers can be explained by misvaluation, as captured by short interest