Mintz Levin Cohn Ferris Glovsky and Popeo is planning to wind down its London intellectual property (IP) practice in the wake of the loss of three patent attorneys to Cooley earlier this month.

Mintz Levin's London managing partner Julian Crump has also left the firm to set up IP boutique Beresford Crump, alongside patent attorney Keith Beresford.

Crump had been with Mintz Levin since 2004. His new firm will focus on IP matters in the pharmaceuticals and life sciences sectors. He is joined at his new firm by fellow Mintz Levin partner Alison Haile.

Earlier this month Cooley hired three patent attorneys from Mintz Levin's London office, David Wraige, Jacqueline Ireland and Daniel Sellwood.

The moves follow on from Cooley's April 2014 hire of former Mintz Levin IP head Ivor Elrifi as a partner in its New York and Boston offices, alongside fellow Mintz Levin partner Heidi Erlacher and four other lawyers.

London IP partners Emma Bevan and Isobel Finnie are still listed on Mintz Levin's website but are expected to leave the firm imminently. It is not clear where they are going.

A source close to the firm said: "The IP practice in London will not exist after the end of the week."

In a statement the firm said: "Mintz Levin will no longer conduct European patent prosecution from its London office.

"The London office will continue to offer corporate services and we will continue to provide European patent prosecution through our correspondent firms, including those our former London colleagues have joined. All US services, including our extensive patent practice, are unaffected."