本文利用國內前六大交易量的券商報告，探討台灣於 2020.10.26實施零股交易後的情況，當券商出具買進推薦的券商報告時，在一個月後的超額報酬卻是負的，這與其自營商在一個月後做出賣出的行為是一致的。另外在券商推薦家數和超額報酬之間是呈現正相關，並且隨著時間拉長有更顯著的現象，最後在該股票自然人比例與超額報酬是呈現負相關的，代表即便零股交易開放了更多自然人進入市場，但是他們對於股價的影響仍然是不顯著的。

The paper examines the situation in Taiwan after the implementation of intraday odd lot trading on October 26, 2020, using top six trading volume domestic brokerage recommendation reports. When brokerage firms issue buy-recommended reports, the excess returns are negative one month later, which is consistent with the proprietary trading department behavior of selling one month later. In addition, the correlation between the number of different brokerage firm with the same recommendation and the abnormal return is positive, and it becomes more significant as time lengthens. Finally, the ratio of natural persons and the abnormal returns is negatively correlated with the abnormal return, which means even though more natural persons have entered the market as a result of intraday odd lot trading, their impact on the stock price is still not significant.

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