The Credibility of Open Market Share Repurchase Signaling
研究发现，高管在回购公告前买入自家股票能增强低估信号的可信度，公告回报与内幕买入正相关，且内幕买入能预测公告后的股票收益。
Abstract Open market share repurchase announcements are commonly associated with equity undervaluation, but their signal about firm value can often be misleading. We conjecture that executives who buy shares of their firm before an announcement add credibility to the undervaluation signal. Consistent with this hypothesis, we find that announcement returns are positively related to past insider purchases, especially for firms that are priced less efficiently. Firms whose insiders bought more shares are also more likely to complete their repurchase plans. Finally, we find that insider purchases predict post-announcement stock returns.