本研究主要從公司治理與管理者固守職位假說的角度來探討內部人持股比率與股利收益率之關係，希望提供更多有關於公司股利行為的解釋面項，以便和其他股利理論作區別。實證結果顯示2003年期間的現金股利迴歸模型，在控制其他監督機制與股利影響因素下，內部人持股比率與現金股利收益率呈一非線性關係。且當內部人持股比率在32%之下，公司股利政策與內部人持有公司的股權在降低權益代理成本上互為替代的公司治理機制。而當內部人持股比率達到32%以上峙，隨著內部人持股的增加而增加管理者固守職位的可能性，公司因此會增加現金股利的發放以達到公司治理機制之間互補的監督效果。本文亦發現內部人持有公司股權的影響力在1998和2003年期間之間有著很重大的改變。尤其是在2003年期間，內部人股權與代理成本之間的關你為非線性關係。由研究結果可推論近年來有愈來愈多的管理者變得更加地鞏固其職權與利益，導致內部人股權的增加在發揮公司治理機制之效果可能有限。此研究結果的發現亦值得目前政府與公司管理者作為設立公司治理機制之參考。

This paper analyses the agency explanation for the cross-sectional variation of corporate dividend policy in the Taiwan by looking at the managerial entrenchment hypothesis drawn from the agency literature. We temp to offer a distinctive set of predictions that cannot be found in other competing stories for the explanation of cross-sectional dividend policy behavior. Especially in the 2003 period, consistent with such predictions, and controlling for other factors, strong evidence is found in the results of cash dividend regressions that a strong U-shaped relationship between dividend yields and insider ownership. Specifically, these findings show that the possibility of managerial entrenchment when insider ownership reaches a threshold of around 32%. Evidence is also presented that the effect of insider ownership changes significantly between the 1998 and 2003 periods; there is evidence that insider ownership is quadratically related to agency costs, especially in the 2003 periods. This is consistent with the anecdotal evidence that many insiders have become entrenched in recent years.