Using a proprietary database of institutional investors’ daily stock trading records in the post-Regulation FD period, this study examines whether transient institutions have the independent ability to correctly process small negative earnings surprise announcements, which management claims transient institutions have difficulty in interpreting. We find economically significant abnormal selling by transient institutions in response to small negative earnings surprises. Transient institutions’ selling in response to small negative earnings surprises is also associated with significant contemporaneous stock price declines. However, we find no evidence that transient institutions’ trading in response to small negative earnings surprises is an overreaction as there is no reversal of stock prices subsequent to transient institutions’ trading. More importantly, we show that transient institutions’ trading in response to small negative earnings surprises helps improve the informational efficiency of share prices.