權益法長期投資之轉投資為我國擴張組織規模的重要方式，透過轉投資所有權發展模式，可能有其正面經濟效益（例如：分散風險、投入資金較少、降低成本、接近市場與稅務規劃等）；然而權益法長期投資之所有權結構繁複，財務報表資訊可能較不容易被外界瞭解而產生資訊不對稱之代理問題，進而衍生對財務報告資訊透明度及可靠性的疑慮。另外，企業若有意圖操縱損益、隱匿非常規交易或進行其他損害股東權益的不適當投資決策時，也比較可能透過較繁複的轉投資方式進行。 本研究考量公司治理內部層級（股份控制權與盈餘分配權偏離程度、董監事持股質押與獨立董監席次）與外部層級（外國法人持股）因素，實證發現股份控制權與盈餘分配權偏離程度越大，或存在董監事持股質押之公司，將降低權益法下投資淨收益（包含具控制力（子公司）與具重大影響力但無控制力之權益法淨收益）之持續性的關聯性；增加獨立董監席次或增加外國法人持股比率，將增加權益法下投資淨收益之持續性的關聯性。故實證結果與本研究推論一致，即公司治理情況越佳（差），將增加（降低）權益法下投資淨收益之持續性的關聯性。另外，實證結果亦顯示股市非理性定價獨立董監席次變數，其對於權益法下投資淨收益之持續性的關聯性；然而股市理性定價其它三項公司治理變數（股份控制權與盈餘分配權偏離程度變數、董監事持股質押變數及外國法人持股比率變數），其對權益法下投資淨收益之持續性的關聯性。本研究亦針對具控制力（子公司）之權益法下投資淨收益之持續性的關聯性，與股市對該關聯性之評價反應之進行測試，其實證結果與對權益法下投資淨收益之測試結果相近。

Taiwan companies frequently expand their organization through pyramidal structures and cross-holdings. Legitimate reasons for firms to expand through complex structures include, among others, capital needs, risk considerations, and government policies. However, complex capital structures could also be used to cover up earnings manipulation and other entrenching behaviors. I hypothesize that the persistence of investment income under equity method is lower for firms with poor corporate governance. I also test whether the stock market can rationally price the connection between corporate governance and the persistence of investment income under equity method. My empirical findings are: the deviation between voting right and cash-flow right and board members' use of shareholdings as collateral to finance (the percentage of shareholdings by foreign institutions and the number of outside board members) are negatively (positively) correlated with the persistence of investment income under equity method. Finally, the results of the Mishkin test reveal that stock market can rationally price the implication of corporate governance on the persistence of investment income except when corporate governance is measured by the number of outside board members. Ultilizing the data availability under special reporting rules of Taiwan, I further test whether the persistence of investment income from subsidiaries is lower for firms with poor corporate governance, and whether the stock market can rationally price the connection of this persistence and corporate governance. My results in this section are similar to those of the first part.