Philipp Bagus explains all, on Mises.org.
Here’s a quote:
“On Thursday, October 28, 2011, prices of European stocks soared. Big banks like Société Générale (+22.54%), BNP Paribas (+19.92%), Commerzbank (+16.49%) or Deutsche Bank (+15.35%) experienced fantastic one-day gains. What happened?
Today’s banks are not free-market institutions. They live in a symbiosis with governments that they are financing. The banks’ survival depends on privileges and government interventions. Such an intervention explains the unusual stock gains.”