全球併購與股市標準累積平均異常報酬之關係： 以台灣上市上櫃公司做為主併者之研究

Abstract

有鑑於臺灣經貿環境日益發達、全球佈局步伐日趨繁湊下，臺灣企業參與或主導併購活動的頻率亦日漸揚升，是故，併購，尤其是全球性的併購，對臺灣企業、學界、政府，乃至於投資人，都是一項關鍵的議題。因此，本研究提出以臺灣企業為主併者，亦即聚焦於臺灣企業主動佈局的思維與角色，對全球進行併購時，國內股市所產生之累積平均異常報酬的分析，以及其成因的研究。 本研究的合併案資料來源為SDC資料庫，而樣本取樣期間為1/1/1990至12/31/2005，取樣標的為臺灣上市、櫃公司為併購案中之主併者，且該併購案之交易金額最少需為100萬美元，總計有109個研究樣本。此外，各樣本相關的股市資訊乃是由臺灣經濟資料庫（TEJ）中所粹擷而得。 本研究的研究法有二：針對標準累積平均異常報酬現象的分析，乃是運用事件研究法；而對於標準累積平均異常報酬的成因分析則採OLS迴歸法分析。 本文研究顯示，此109個合併案的主併者，其標準平均異常報酬及標準累積平均異常報酬之顯著峰值乃於宣告日後一交易日顯現，而並非宣告當日，這也符合了我國既有的「上市上櫃公司及興櫃股票公司合併或分割應注意事項」及「對上市公司重大訊息說明記者會作業程序」的法條規範之精神，而值得注意的是，此峰值為正向而非負向。而在潛在成因的研究方面，本研究共探討了六個可能的因子，即「主併者之產業」、「多角化程度」、「牽涉區域配對」、「宣告年度」、「交易後持股比例」，及「交易金額」，而研究顯示唯「多角化程度」具顯著影響，但解釋能力仍不大，亦即上述六個因子，無法顯著證明為此109個合併案所致的主併者標準累積平均異常報酬之直接影響成因，此原因可能是臺灣為新興經濟體，與成熟經濟體的歐美經濟行為不同，且臺灣股市結構與美股不同所致。

The study originates from the intention to investigate the standardized cumulative average abnormal returns (SCAR) in the stock market and the possible determinants in of the M&A activities, especially the global ones, with Taiwanese enterprises as acquirers due to the topics’ increasing significance and urgent necessity for the enterprises, academia, government, and investors as well under the more prosperous economic environment and more rapid globalization tide. The M&A data were collected from the SDC database with the sampling period from 1/1/1990 to 12/31/2005. The samples are the Taiwanese listed or OTC companies which act as the acquirers in the M&A cases with the transaction scale higher than USD 1 million, amounting to 109 qualified cases. Additionally, the stock market related information was collected from the TEJ databases. Two methodologies are employed in this research. For the investigation on the SCAR, the event study serves; for the analysis of the determinants, the OLS regression functions. Findings of the 109 M&A cases show that the SCAR reaches the peak on the next effective transaction date to the date announced instead of the date announced, complying with the regulations and the spirit of “Guidelines for Mergers or Splits by Listed, OCT, and Emerging Stock Companies” and “Taiwan Stock Exchange Corporation Procedures for Press Conferences Concerning Material Information of Listed Companies”. However, the peak appears to be positive instead of negative. As to the analyses of the determining factors, six variables are examined: acquirer’s industry, diversification, region match, year announced, percentage owned after the transaction, and the transaction scale. The statistical results show that, only diversification surfaces the significant impact on SCAR but with a low R2. That is, the six factors couldn’t be directly verified to contribute to SCAR. The reasons why may be attributed to the different economic stage that Taiwan locates in and U.S.A. belong to. In other words, the emerging economic behavior would diverge from the developed one. In addition, the distinct structures of stock markets in Taiwan and in U.S.A also serve the potential cause.