Actual Share Repurchases, Price Efficiency, and the Information Content of Stock Prices
利用美国股票回购的手工数据，研究发现回购使股价更有效、降低异质风险，尤其在市场下跌时提供价格支撑，且未发现管理层利用回购操纵股价。
We examine the impact of actual share repurchases on stock prices using several measures of price efficiency and manually collected data on U.S. repurchases. We find that share repurchases make prices more efficient and reduce idiosyncratic risk. Further analyses reveal that the effects are primarily driven by repurchases in down markets. We conclude that share repurchases help to maintain accurate stock prices by providing price support at fundamental values. We find no evidence that managers use share repurchases to manipulate stock prices when selling their equity holdings or exercising stock options. Received June 1, 2015; accepted June 1, 2016, by Editor David Denis.