Shareholder litigation in mergers and acquisitions

Using hand-collected data, we examine the targeting of shareholder class action lawsuits in merger and acquisition (M&A) transactions, and the associations of these lawsuits with offer completion rates and takeover premia. We find that M&A offers subject to shareholder lawsuits are completed at a significantly lower rate than offers not subject to litigation, after controlling for selection bias, different judicial standards, major offer characteristics, M&A financial and legal advisor reputations as well as industry and year fixed effects. M&A offers subject to shareholder lawsuits have significantly higher takeover premia in completed deals, after controlling for the same factors. Economically, the expected rise in takeover premia more than offsets the fall in the probability of deal completion, resulting in a positive expected gain to target shareholders. However, in general, target stock price reactions to bid announcements do not appear to fully anticipate the positive expected gain from potential litigation. We find that during a merger wave characterized by friendly single-bidder offers, shareholder litigation substitutes for the presence of a rival bidder by policing low-ball bids and forcing offer price improvement by the bidder. ► Using hand-collected data, we examine M&A shareholder class action lawsuits. ► M&A offers subject to these lawsuits are completed at a significantly lower rate. ► M&A offers subject to these lawsuits entail significantly higher takeover premia. ► There is a positive expected gain to target shareholders from such litigation. ► Shareholder litigation polices low-ball bids and forces offer price improvement.