At least 1000 hedge funds, one in eight of the worldwide total, are trying to unwind investments held by their prime brokers amid moves today by investment firm Olivant to recover its 2.78% holding in UBS, which was held in accounts managed by Lehman Brothers in Europe.

More than one-fifth of those trying to move assets from Lehman and other prime brokers manage more than $1bn (€707m), and are moving after "confusion and disarray" drove home just how much a fund's operational integrity is based on the health and good judgement of its prime brokers, according to analysis by US hedge fund technology provider Paladyne Systems.