A Case Study of Illegal Insider Trading — The Scandal of Vultures' Insider Trading

The purpose of this paper is to look at the duration of the four-month period before the window dressing of Power Quotient International Co., LTD. (PQI) annual report between 2004 and 2005 was disclosed. The vultures sold 6,373,000 shares of PQI's stock based on the illegally obtained insider information. The empirical results indicate that the vultures' selling did not make PQI's stock price go down during insider period, but PQI's stock price did appear to rise and significantly exceeded the non-insider period. However, the proportion of vultures' selling is negatively correlated with the changes in PQI's stock price. The effect of vultures' selling is indifferent from the effect of non-vultures' selling during insider period. Market liquidity is also affected unfavorably in the presence of vultures' trading. Additionally, the newspaper's reports on PQI's positive or negative news significantly influence the investment decision of investors in Taiwan, and significantly influence the PQI's price changes and market liquidity.