What Do Independent Directors Know? Evidence from Their Trading
比较独立董事与其他高管买卖自家公司股票的表现，发现独立董事买入时能获得显著正异常收益，且与高管差距不大；在治理最差的公司中两者收益更高，审计委员会成员收益高于其他独立董事，独立董事在坏消息前和财报重述期间卖出也能获异常收益。
We compare the trading performance of independent directors and other executives. The findings reveal that independent directors earn positive substantial abnormal returns when they purchase their company stock, and that the difference from the same firm's executives is relatively small at most horizons. We also find that executives and independent directors make higher returns in firms with the weakest governance, the gap between these two widens in such firms, and that independent directors sitting on the audit committee earn higher returns than other independent directors at the same firm. Independent directors also earn significantly abnormal returns when they sell the company stock in a window before bad news and around earnings restatements. The Author 2009. Published by Oxford University Press on behalf of The Society for Financial Studies. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org., Oxford University Press.