The IRRC data set is not an exhaustive listing of all provisions. Although firms can review their listing and point out mistakes before publication, the IRRC does not update every company in each new edition of the book, so some changes may be missed. Also the charter and bylaws are not available for all companies and thus the IRRC must infer some provisions from proxy statements and other filings. Overall, the IRRC intends its listings as a starting point for institutional investors to review governance provisions. Thus, these listings are a noisy measure of a firm's governance provisions, but there is no reason to suspect any systematic bias. Also, all of our analysis uses data available at time t to forecast performance at time t + 1 and beyond, so there is no possibility of look-ahead bias induced by our statistical procedures.