规范化的信息披露是证券市场正常运转的基石。本文利用重大事件披露违规公司研究信息披露违规背后是否存在股价异常波动与内幕交易现象,并将样本公司按照处分类型和公司类型分类检验。研究表明,总体样本公司的股票存在显著的内幕交易行为,并呈现出牛市背景下的新特征:受到公开谴责的公司股票内幕交易程度显著高于受到公开处罚的公司股票,ST公司股票的内幕交易程度显著高于非ST公司股票。
Normative information disclosure plays an important role in the securities market. This paper discusses the problems of stock price abnormal volatility and insider trading using the sample of illegal disclosure companies, classifies and analyzes the sample companies. The results show there is insider trading in the process of material facts disclosure, insider trading and manipulation activity exhibit new character in ascending market. The insider trading degree of companies being criticized is larger than that of companies being punished, and the degree of ST companies is larger than that of non-ST companies.