本研究主要探討伊斯蘭教法、所有權結構與投資效率之關係，並以印尼2012至2021年上市公司為樣本進行實證分析。依據過去文獻，本研究提出假說1遵行伊斯蘭教法的公司，投資效率越高；當加入所有權結構，並將所有權結構分為法人持股與內部人持股時，本文提出假說2，遵行伊斯蘭教法的公司，法人持股越高，投資效率越高；假說3遵行伊斯蘭教法的公司，內部人持股越高，投資效率越低。本研究實證結果發現遵循伊斯蘭教法的公司會有較高的投資效率；加入所有權結構後，發現遵循伊斯蘭教法的公司，法人持股越高，投資效率越高；遵循伊斯蘭教法的公司，內部人持股越高，投資效率越低。最後，本研究加入COVID-19疫情對投資效率的影響。本文實證結果顯示，伊斯蘭教法與COVID-19疫情對投資效率呈現負向影響；在加入法人持股後，COVID-19疫情期間遵循伊斯蘭教法的公司，法人持股越高，對於投資效率無顯著影響；然而加入內部人持股後，COVID-19疫情期間遵循伊斯蘭教法的公司，內部人持股越高，投資效率會越低。顯示宗教與所有權結構對投資效率的影響，會因環境的劇烈變動而有差異性的影響。
This study examines the relationship between Islamic law, ownership structure and investment efficiency, and uses the sample of listed companies in Indonesia from 2012 to 2021 for empirical analysis. According to the previous literature, this study proposes hypothesis 1 that follow Islamic law have higher investment efficiency; when ownership structure is added and divided into institutional ownership and insider ownership, this paper proposes hypothesis 2 that follow Islamic law have higher institutional ownership, the higher the investment efficiency; and hypothesis 3 that follow Islamic law have higher insider ownership, the lower the investment efficiency. The empirical results of this study found that companies that follow Islamic law will have higher investment efficiency; After adding the ownership structure, it is found that companies that follow Islamic law have higher institutional ownership and higher investment efficiency; Companies that follow Islamic law, the higher the insider ownership, the lower the investment efficiency.
Finally, this study incorporates the impact of COVID-19 on investment efficiency. The empirical results of this paper show that Islamic law and COVID-19 have a negative impact on investment efficiency. After adding institutional ownership, companies that follow Islamic law have no significant impact on investment efficiency during the COVID-19 period. And after adding insider ownership, during the COVID-19 period, for companies that follow Islamic law, the higher the insider ownership, the lower the investment efficiency will be. It shows that the impact of religion and ownership structure on investment efficiency will have differential effects due to drastic changes in the environment.
