Silver was project manager on the Foster and Partners schemes for Stansted airport, the Cambridge law faculty, the Commerzbank headquarters in Frankfurt and the Sackler galleries at the Royal Academy of Arts in London.
Foster and Partners recently restructured by creating six main working groups under the control of key directors. Silver missed out on leadership of one of the six groups, but as a part-time employee he was not considered.
Silver will leave Foster at the end of next month and will become a part-time director at Hamilton Associates in August.
He said: "I'm very much looking forward to working with Robin, who I never actually worked with on a project at Foster's. It will be a very interesting range of work."