Custodians, brokers and investment banks are considering a potentially “onerous” policy statement from the UK regulator, which will demand they supply information on the assets of a client 48 hours after a firm goes bust.

The new rule is designed as a quick way to preserve assets in the event of financial collapses such as Lehman Brothers and MF Global. Ownership of Lehman assets are still being fought over four years after the bank's demise; the asset hunt at MF Global is six months old, so far.