내부자매도·매수에 따른 차별적 거래행태 및 공시전략

Insider sell and buy have negative and positive information characteristic, respectively. And managers have tendency to avoid exposure of negative information more than positive information. Furthermore, limited financial resource makes insiders compare uncertainty of return on/of investment for insider buy with any other alternative investment options. However, in case of insider sell, they can avoid more losses from their own stocks by selling them early before negative information spread in the stock market. Those characteristic differences between insider buy and sell would cause differential trading and disclosing behaviors. The results of empirical analysis are as follows. First, insider sell shows higher daily trading volume and lower annual trading frequency than Insider buy. Second, insider sell have higher disclosure frequencies on Friday than Insider buy. The empirical results raise the problem of insider trading disclosure system in Korea, which allows high discretion to top managers to hide negative information of insider sell. Based on our empirical results, we suggest that revision and supplementation of insider trading disclosure regulation are necessary. This study contributes to academics and regulators as follow. While existing insider trading mainly focused on information effects, this study expands the issue to discriminatory transaction behaviors and disclosure incentives between insider trading transactions of sell and buy. Our study provides empirical evidence of manager’s opportunistic behavior exploiting insider trading disclosure rule in Korea, which allows more discretion in making disclosure timing decision than U.S.