許多文獻探討過初次公開發行對其發行公司本身的影響。而近期也有一些研究再討論初次公開發行宣告對其競爭者的影響。本文將探討範圍擴大，研究初次公開發行對競爭者以及其上下游的影響。我們發現其競爭著對於初次公開發行宣告的反應結果分為資訊效果以及競爭效果。而在競爭者存在不同效果下，其上下游產業也面臨不一樣的反應。在資訊效果下上下游產業具有正面反應。相反的，在競爭效果下，對於上下游則是產生負面的效果。另外，本文發現，在資訊效果下，初次公開發行公司的公司規模對於競爭者和上下游產業的財富效果具有正向的關係。我們也懷疑可能存在其他對於異常報酬更具解釋力的變數。 Previous literatures examine the direct effect of the IPO on the firm foundation. Recently, some researches examine if the IPOs announcement has industry-wide effect. We broaden the investigation through the whole supply chain by examining the wealth effect of IPOs announcement on the rivals, customers and suppliers. This paper finds that when the rivals are under the information effect, the customers and suppliers will suffer positive effect. Otherwise, when the rivals are under the competition effect, the customers and suppliers will suffer negative effect. Moreover, the size of the IPO firm is significantly positively related with the CAR of the rivals, customers and suppliers. We conjecture that there are still some variables which would be more powerful in explaining the abnormal return of the rivals, customers and suppliers.
