The informational consequences of good and bad mergers
研究了并购公告如何影响收购方股票价格的信息含量，发现低信息含量的收购方在公告后信息含量显著上升，而高信息含量的则下降，分析师覆盖也有类似变化。
We study the information production dynamics in financial markets in response to Mergers and Acquisitions (M&As) announcements. We find that acquirers with low levels of pre-announcement stock price informativeness experience a substantial increase in their corresponding post-announcement stock price informativeness in response topositive Cumulative Abnormal Returns (CAR). We show that this increase is due to the enhanced prospect of deal completion. By contrast, high levels of acquirer pre-announcement stock price informativeness limit traders’ incentives to search for, and acquire, new information. We also find that similar dynamics apply to the changes in acquirers’ analyst coverage. Emphasizing the important role of information acquisition costs in influencing informed trading, a positive acquirer CAR increases the acquiring firm’s post-announcement stock price informativeness in M&As involving public rather than private and subsidiary targets. Overall, we show that M&As have important informational consequences beyond their immediate effects on stock prices.