In both the subprime crisis and the euro-area crisis, regulators imposed bans on short sales, aimed mainly at preventing stock price turbulence from destabilizing financial institutions. Contrary to the regulators’ intentions, financial institutions whose stocks were banned experienced greater...

We present a model in which issuers of structured bonds choose coarse and opaque ratings to enhance the liquidity of their primary market, at the cost of reducing secondary market liquidity or even causing it to freeze. The degree of transparency is inefficiently low if the social value of...