Deutsche Bank shares slide 11% after sudden spike in the cost of insuring against its default

Deutsche Bank shares fell by more than 11% on Friday following a spike in credit default swaps Thursday night, as concerns about the stability of European banks persisted.

The German lender’s Frankfurt-listed shares retreated for a third consecutive day and have now lost more than a fifth of their value so far this month. Credit default swaps — a form of insurance for a company’s bondholders against its default — leapt to 173 basis points Thursday night from 142 basis points the previous day.

The emergency rescue of Credit Suisse by UBS, in the wake of the collapse of U.S.-based Silicon Valley Bank, has triggered contagion concern among investors, which was deepened by further monetary policy tightening from the U.S. Federal Reserve on Wednesday.