我國政府於2002年制定「企業併購法」，旨在協助企業透過併購進行組織調整，並提升企業經營效率，同時兼顧股東權益。然而過去學者的研究結果顯示，併購對廠商績效表現的影響並不一致。這可能是因為不同產業、地點、時空背景或研究方法的差異所導致，因此本文將以台灣製造業廠商於2004年至2020年期間發生之併購事件作為研究對象進行探討。另外為深入了解不同時期併購效果，將時間拆分為2004年至2008年、2009年至2014年以及2015年至2020年，並且使用傾向分數配對法(PSM)結合雙重差分法(DID)的模型，以探討併購活動對廠商績效及表現之影響，提供併購相關研究不同面向的資訊，以豐富現有的研究知識。
本文以總要素生產力及員工平均薪資作為績效表現影響的變數，實證結果顯示僅在2015年至2020年的區間中，併購對於總要素生產力及員工平均薪資具有顯著的正向影響，並且觀察到國外併購效果與整體併購效果具有顯著正向差異，以及在區分併購類型的情況下，亦發現水平併購效果與垂直併購效果皆顯著大於整體併購效果，其中又以水平併購效果最為強烈。另外本研究亦發現，併購效果可能並非在廠商併購後立即出現，部分區間顯示併購效果必須至併購後第四期及第五期才會慢慢出現，這將可能是導致在2004年至2008年以及2009年至2014年區間中，未觀察到整體併購效果的原因。最後本文亦發現市場中規模較大、研發投入較高、Tobin’s Q較高、以及生產力較高的廠商，其參與併購的機率就愈高。

Taiwan government enacted the "The Business Mergers and Acquisitions Act" in 2002, aiming to assist companies in conducting organizational adjustments through mergers and acquisitions, while enhancing operational efficiency and considering shareholder interests. However, previous research by scholars has shown inconsistent effects of mergers and acquisitions on firm performance. This could be attributed to differences in industries, locations, temporal contexts, or research methodologies. Therefore, this study focuses on merger and acquisition events in the Taiwanese manufacturing industry from 2004 to 2020. To gain deeper insights into the effects of mergers and acquisitions during different time periods, the study divides the timeframe into three intervals: 2004 to 2008, 2009 to 2014, and 2015 to 2020. By using the propensity score matching (PSM) method combined with the difference-in-differences (DID) model, the study aims to investigate the impact of merger and acquisition activities on firm performance and outcomes. It intends to provide additional perspectives and enrich existing research knowledge in the field of mergers and acquisitions.
The variables of total factor productivity and average employee salary are used in this study as indicators of performance. The empirical results reveal that the impact of mergers and acquisitions on total factor productivity and average employee salary is significantly positive only during the period of 2015 to 2020. Furthermore, significant differences are observed between the effects of foreign acquisitions and overall acquisitions. Additionally, when distinguishing between different types of mergers, both horizontal and vertical mergers show significantly greater effects compared to overall mergers, with horizontal mergers exhibiting the strongest impact.Moreover, the study finds that the effects of mergers and acquisitions may not be immediate. Some periods indicate that the effects of mergers and acquisitions become evident only in the fourth and fifth periods after the merger, suggesting a delayed manifestation. This may be one of the reasons why overall merger effects were not observed during the periods of 2004 to 2008 and 2009 to 2014.Lastly, the study also finds that larger firms with higher research and development investments, higher Tobin’s Q, and higher productivity are more likely to engage in mergers and acquisitions.

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