本研究主要探討企業分割宣告對股價的影響及企業在分割後之長期股價表現與經營績效變化.本研究實證結果:(一)在宣告期間母公司的股價反應：母公司於宣告期間之股價為不顯著負的異常報酬。(二)在分割後母子公司的股價表現：母公司分割宣告日後之累積異常報酬為正，而子公司上市(櫃)後之累積異常報酬為負的。(三)在分割後母子公司的營運績效表現：母公司在分割後所衡量之經營績效的表現普遍比分割前之經營績效的表現來得好，顯見分割對母公司之經營績效有很大的改善。而子公司在分割後之經營績效的表現並未優於分割前，子公司的經營績效並不穩定，其經營績效並不優於母公司。另以分割動機，跨產業分割(聚焦)或同產業分割(非聚焦)來觀察，無論是聚焦分割或非聚焦分割，母公司之長期累積異常報酬及財務績效表現均比分割前的表現好，但子公司分割後之表現就未有正面的反應。This study investigates the stock price impact on the spin-off declaration and the long-term stock and operating performance of firms following the spin-off.The empirical results can be summarized in the following points：(1) The announcement abnormal return of the parent firms is insignificantly negative. (2) For the long-run post-performance, the parent corporations outperform their benchmark and the subsidiary firms underperform their peers. (3) The operating performance of the parent corporations improves materially after the break up of the operational divisions. Overall, the empirical results confirm that the operation performance of the parent corporations is improved by the corporate focus, while the performance of spun-off firms is not improved.For the motivation, the parent corporations have improved their operating performance, for both of with-in industry and cross-industry spin-offs. On the other hand, the performance of the subsidiary firms is not dramatically improved.
