"This paper analyzes the performance of the commercial mortgage-backed security (CMBS) market before and during the recent financial crisis. Using a comprehensive sample of CMBS deals from 1996 to 2008, we show that (unlike the residential mortgage market) the loans underlying CMBS did not...

We study credit ratings on subprime and Alt-A mortgage-backed-securities (MBS) deals issued between 2001 and 2007, the period leading up to the subprime crisis. The fraction of highly rated securities in each deal is decreasing in mortgage credit risk (measured either ex ante or ex post),...