本研究利用事件研究法探討華為孟晚舟事件對華為台灣供應鏈廠商股價是否產生異常報酬，並進一步檢定收押事件在股票市場中所呈現之反應效率。從檢定結果顯示，當華為財務長孟晚舟被收押時，除事件日後第3天之異常報酬其P值呈現極為顯著之外，事件期間其餘各日之P值皆呈現非常不顯著之現象，此現象說明了台灣華為供應鏈之上市櫃公司對於華為孟晚舟事件此重大事件呈現先無感再遲鈍之不可思議的反應。顯示台灣股票市場對此事件之無感反應，不僅未呈現傳統台股實證研究所認定的半強式效率市場，甚至連弱式效率市場都不及的結果。

This study intends to examine whether the Huawei CFO Meng Wanzhou's arrest will result in significant stock abnormal rates of return of Huawei's Taiwan supply chains by event study methods. Our empirical results show that negative abnormal returns were not found significantly on any day of the whole event period except the third day after the event day. The findings reveal that the stock performance of Huawei's Taiwan supply chains tends to be insensitive and then slowly reacts under the event impact, showing an extraordinary sub-weak form of securities markets. The phenomenon highlights that active investors could take advantage of this promising opportunity to go for short selling and reap handsome profit in such an international economic and trade conflict event.