The Credibility of Voluntary Disclosure and Insider Stock Transactions
研究高科技公司自愿披露创新战略时股价的反应，发现内部人买入能增强披露可信度，且该效应在信息不对称程度高的公司中更强。
ABSTRACT We examine stock price reaction to voluntary disclosure of innovation strategy by high‐tech firms and its relation with insider stock transactions before the disclosure. We find that, despite the qualitative and subjective nature of strategy‐related disclosure, there is positive stock price reaction to the disclosure. The evidence suggests that investors view the disclosure as credible good news. We also find that the disclosure is associated with more positive stock price reaction when it is preceded by insider purchase transactions. This evidence is consistent with insider purchase enhancing the credibility of the disclosure. The credibility‐enhancing effect is found to be stronger for firms with higher degrees of information asymmetry (younger firms, firms with lower analyst following, loss firms, and firms with higher research and development (R&D) intensity). Our evidence also indicates that predisclosure insider purchase is associated with greater future abnormal returns, suggesting that managers are privy to good news shortly before the disclosure.