宣告及實際買回庫藏股與異常報酬－－管理者之策略性應用

Announced and Actual Share Repurchases and Abnormal Returns: Managers’ Strategic Application

本研究旨在探討公司宣告買回庫藏股佔其流通在外股數比例大小與市場反應（股價績效）大小之關係，以及公司實際購回佔其宣告買回之比例與其股價被低估程度及公司現金流量水準之關係。實證結果顯示公司宣告買回庫藏股比例與宣告期間平均異常報酬有顯著正向相關，但實際購回比例卻與宣告期間平均異常報酬無顯著相關；此結果顯示台灣市場反應庫藏股實施之資訊內涵係來自宣告買回而非實際買回。實證結果亦顯示庫藏股宣告購回比例及前次宣告之實際購回比例皆與當次宣告之實際購回比例呈顯著正向相關，但宣告前一個月之平均異常報酬、宣告期間之平均異常報酬（亦即股價被低估之程度）及宣告前一季之現金流量水準皆對實際購回比例無顯著影響。 This paper examines the relation between abnormal returns at the announcementperiod and the fraction of shares stated in the announcement of the repurchase program,and the effect of undervaluation and cash flows on actual repurchases. The empiricalresults show that larger announced repurchase targets are associated with higher abnormalreturns, but there is insignificant association between abnormal returns and the firm’sactual share repurchases at the announcement period. These results indicate that theinformation content of the repurchase announcement in Taiwan comes from announcedtargets but is unrelated to actual repurchases. The results also show that there aresignificantly positive effects of announced repurchase targets of this time and actualrepurchases of prior time on actual repurchases of this time, but there are insignificanteffects of preannouncement performance, announcement period performance andpreannouncement cash flows on actual share repurchases.