The empirical results indicate that not only uptick block trading but also downtick block trading there is no evidence of any option price reaction before the block trade.

• 藉以观察选择权价格产生异常波动的时点，是否确实早于股价的波动。实证结果发现，选择权市场并未明显有私有资讯者先行(偷跑)的情形产生。