Credit default swaps hardly used to be a subject to keep people awake at night. No longer. Designed as insurance for a company’s creditors against its default, issuance of such derivatives exploded in recent years. But transparency failed to keep pace and the bankruptcy of Lehman Brothers last month turned into a nightmare for global finance.

Largely unfettered by regulation, the $58,000bn market evolved with over-the-counter transactions. The absence of a clearing house, where trades are recorded and cleared, has now come to haunt investors.