Alex Ehrlich, the former Goldman Sachs banker who switched to be global head of prime services at UBS roughly six years ago, has left the Swiss bank and is thought to be joining Morgan Stanley as head of its prime brokerage unit.

Ehrlich, who left Goldman Sachs after missing out on promotion to the US firm's top partner echelon and subsequently hired several prime broking staff from the bank over to UBS, has left the Swiss group, where he was the US-based global head of prime services, according to a source familiar with his departure.