The collapse of Lehman Brothers has had many unexpected consequences, not least a potential undermining of the prime brokerage business model. This is opening the door to custodians to target a market they have coveted for years.

Steve Ingle, derivatives product manager at BNY Mellon Asset Servicing, believes competition between custodians and prime brokers is growing. He said: "It is going to be a fraught environment for the next few years.