When Paul Weiss Rifkind Wharton & Garrison hired Simpson Thacher & Bartlett corporate partner Alvaro Membrillera earlier this year, the move marked the elite US firm's first lateral hire in London since it first opened in the City 16 years ago.

Given the firm's London base had been led by the same two partners – Mark Bergman and David Lakhdhir – ever since its 2001 launch, it is fair to say the hire came as a surprise to many.