Trading options and CDS on stocks under the short sale ban

We analyze price discovery in the options and CDS markets during the 2008 short-sale ban. Among the banned stocks, those with high open-purchased put–call ratios, low synthetic-to-stock price ratios, or high CDS rates exhibit poor performance in the following days. Additionally, options prices are more efficient for unbanned stocks during the ban period. These findings suggest that informed investors engage in derivative trading during highly distressed market conditions and that derivative prices contain more information about stock prices during the ban.