本研究採用個案研究法，透過次級資料分析及財務報表評估和比較分析，來探討Y個案公司之購併歷程與結果。2011年4月Y證券公司成功地購併寶來證券，Y公司除了支付260億元現金，並發行約10億股新股以購併寶來證，換算總收購價達新台幣489億元；若以淨值估算，溢價超過七成；若以股價換算，溢價幅度約11.6%；雙雙創下證券業購併史上新高紀錄，因此本個案相當具有探討及分析價值。本研究透過財務報表分析，比較個案公司在購併案完成後之營運及財務綜效表現。研究結果發現：Y公司購併寶來證券後，其營運費用率明顯下降；各業務之市占排名不僅位居龍頭地位且大幅領先同業；財務報表ROA、ROE及EPS分別較購併前成長37%、42%及58%，證明其購併後之綜效相當顯著。

This research conducted a case study using the secondary data and financial reports to explore the context and analyze the results for the Y financial holding company after completing merger and acquisition (M&A) process. Case Y successfully merges and acquire the Taiwan-based Polaris Securities Company in 2011. To acquire Polaris Securities, Y company needed to pay 26 billion NT dollars in cash and issue approximate one billion new shares. The total acquisition cost was about 48.9 billion NT dollars which was over 70% premium in net value estimation, and around 11.6% of premium percentage by converting into share price. Since it is the largest M&A case of securities firms in Taiwan, its operating synergy after M&A is worth to be explored. The results showed that Y company's operating expenses apparently decreased after merging Polaris, and its market share was at top rank leading ahead in the banking and finance industry. Besides, the financial reports such as ROA, ROE and EPS all showed great growth rates of 37%, 42%, and 58%, respectively. It proved that the decision of M&A was quite correct and its synergy was significant.