Stock Repurchase as a Takeover Defense
构建模型，说明经理人通过股票回购向市场传递公司价值高的信号，从而阻止收购；回购虽提升股价但也增加风险，且导致收购数量低于有效水平。
We develop a model in which stock repurchases serve as a defense against takeovers by signaling the manager’s private information about the value of the firm. The manager repurchases shares to block a takeover only if the cost of doing so is not too high. Since the cost is inversely related to the value of the firm under his management, a repurchase signals that the value of the stock is high, blocking a takeover. While a repurchase increases the expected value of the stock, it also makes the stock riskier. The model also implies that there are too few takeovers for efficiency.