本文主要探討所有權結構與多角化策略間之動態關係，並以中國大陸2003年至2008年間，上海證券交易所上市之企業為樣本，進行簡單差異分析，以檢測中國大陸上市公司所有權類型的變革對多角化策略間之動態關係，並探討股權分置改革對所有權與多角化策略間關係之影響。 實證結果發現，在全樣本期間，持有可交易股的國有企業對多角化程度有正向動態影響。然而，當考慮股權分置改革之影響後，發現，在股改前，國有企業所有權對多角化程度無動態影響；然而，在股改後，不論國有企業持有股權是否為可交易股，對多角化策略均具有正向的動態影響，顯示國有企業並未因為股權分置的改革，而改變其策略思維，反而更服膺中國政府的政策需要而積極多角化，支持國有企業負有政治成本的假說；在法人股東企業方面，所有權結構對繼之而起的多角化程度，在全樣本期呈顯著的正向動態影響，而股權分置的改革對其多角化程度則不具顯著動態關係，顯示中國法人股東在管理思維上與西方法人股東有著迥然不同的特性，並表現在極具差異性的公司監督管理實務上。 總而言之，政府的強大力量，仍是左右中國國有企業管理的重要推手，而股權分置改革希冀帶來的管理變革，在公司策略形成上，仍未有重大成效。 This paper examines the dynamic relationship between ownership style and corporate diversification as well as the impact of Split Share Reform on this relationship. Using a sample of listed firms in Shanghai Stock Exchange from 2003 to 2008 and the simple difference approach, we find that national enterprises with tradable shares have a positive dynamic influence on diversification in all sample period. Before the share reform, national enterprises did not have any dynamic effects on diversification. However, after the reform, national enterprises have a positive dynamic influence on diversification. Consistent with the political cost hypothesis, our results indicate that government is still important on national enterprises’ management. About legal person enterprises, we find that there are dynamic effects on diversification in all sample period and not in Split Share Reform, it shows that management behavior on Chinese legal person is not similar to Western legal persons. In conclusion, these results show that the Chinese national enterprise reform does not have a significant effect on the strategic thought of diversification; the authority of government is still the determinant.
