上市公司信息泄露减少了吗?——基于《上市公司信息披露管理办法》实施前后的比较

Has Information Leakage of Listed Companies Decreased? Based on Comparison pre and post Implementation of “Administrative Measures on Information Disclosure by Listed Companies”

运用事件研究法对《上市公司信息披露管理办法》实施前后两年,即2005—2009年深沪两市A股业绩预告利多、高送转和增发三类重大事件信息披露的市场反应进行实证分析,利用内幕交易和信息泄露程度测度上市公司信息披露的公平性,检验了《上市公司信息披露管理办法》的实施效果。结果显示,信息公平披露规则在实施当年的短期内发挥了作用,但总体效果并不明显,信息泄露程度呈先下降后回升的趋势,内幕交易依然存在。为此,应进一步加强信息披露的监管,加大对违规信息披露的处罚力度;在强调公平信息披露的同时,关注上市公司信息披露的及时性;正确处理好资本市场效率与信息披露公平两者之间的关系。

The thesis empirically analyses market response of annual performance projection,high dividend payout and new issuance of listed companies in share A at Shenzhen and Shanghai Stock Exchanges pre and post of implementation of ＂Administrative Measures on Information Disclosure by Listed Companies＂ in 2005-2009 by using event study.Justice of companies listed information disclosure is measured by using insider trading and information leakage degree to test implementation results of it.The results show that fair information disclosure rules play a role in short-term,but its effect is not obvious as a whole.Information leakage degree descends firstly and then picks up while insider information to trade still exists.Therefore,we should strengthen supervision of the information disclosure,reinforce punishment of illegal information disclosure,pay attention to timeliness of listed companies information disclose while emphasize its fairness,handle relationship of capital market efficiency and information disclosure fair correctly.