This article explores the price behavior of a sample of corporate securities in which trading was temporarily suspended by the SEC. Suspensions are found to coincide with substantial devaluations of the suspended securities. Further, significant and prolonged negative abnormal returns are observed in the postsuspension period, an apparent violation of semistrong form market efficiency.

A vector autoregressive (VAR) model is used to examine the relation between aggregate insider transactions and stock market returns. Consistent with the extant literature, there is some predictive content associated with aggregate insider transactions, but its magnitude is slight. In contrast, market returns have substantial influence on the aggregate purchases and sales of corporate insiders. The findings suggest that: 1) the degree of mispricing observed by insiders is small; 2) very little of the mispricing is associated with unanticipated macroeconomic factors; and 3) investors cannot use aggregate insider transactions to profitably predict future market returns over the following eight weeks.