本研究以大同集團為個案研究對象，從決策及資源分配掌控者觀點定義該集團企業之最終控制者，首先分析大同集團企業之董監結構及股權結構，並針對該集團之公司治理議題作探討，亦對相關之法令缺失，提出改善及政策建議。 研究結果顯示，大同集團企業之最終控制者林蔚山家族係透過交叉持股及掌握董事會席次控制權等控制途徑掌控集團企業，其集團內十一家公開發行以上公司的平均直接持股率、股份控制權、盈餘分配權分別為1.17%、21.83%、1.07%，但平均席次控制權則高達61.85%，股份控制權（席次控制權）與盈餘分配權偏離差之平均值則達20.76%（60.79%），席次控制權與盈餘分配權之偏離倍數為178.01倍，亦即最終控制者可以一單位的出資獲取178單位以席次控制力衡量的實質控制力。大同集團企業席次控制權與盈餘分配權嚴重偏離之個案研究發現，符合經營者之經營誘因不足，而財富侵佔動機較強之學術假設。此外，本研究探討該集團企業掏空資產案件、大幅減資、投資通達國際之相關財務資訊透明度，針對大同集團之股權結構與董監組成分析，提出公司治理相關議題討論。最後，本研究針對公司治理相關法令，提出改善及政策建議。 關鍵詞：集團企業、股權結構、公司治理、席次控制權 / This study employs the Tatung business group as our sample and defines the ultimate owner as the entity with ultimate influence over major decisions regarding the operation, management, and allocation of company resources. We first analyze the characteristics of different boards of directors and corporate ownership structure of the Tatung business group. Corporate governance related issues are then identified, followed by discussions on the deficiencies of relevant regulations and suggestions for improvements on government policies. The analysis indicates that cross-holdings, pyramid structure and seat control over the board members are approaches applied by the Lin Family to actively control the Tatung business group. An analysis on the measurement of voting rights, cash flow rights and board seat-control shows that direct shareholding, voting rights and cash flow rights are on average 1.17%, 21.83% and 1.07%, respectively, while the board seat-control ratio is 61.85%. The average deviation between voting right (board seat-control) and cash flow rights is 20.76% (60.79%). The number of board seats controlled by the owner is 178.01 times greater than cash flow rights. In other words, the ultimate owner gets approximately 178 units of controlling power through one unit of capital input. To the extent that ownership and control is highly deviated, a weaker disciplinary effect and a stronger entrenchment effect can be expected. In addition, in this study of the Tatung business group, we examine the emptied assets case, significant capital reduction, and the transparency of financial information of investment in Nature Worldwide Technology Corporation. For the corporate ownership structure and the characteristics of different boards of directors of the Tatung business group, we identify the critical issues regarding corporate governance. Finally, discussions on the deficiencies of relevant regulations and suggestions for improvements on government policies are provided. Keywords: Business group; Corporate ownership structure; Corporate governance; Board seat-control.