Law firm Proskauer has strengthened its global capital markets team by adding three partners and a senior counsel in London, effective September. Partner Peter Castellon joins from Citigroup in London, where he works as deputy general counsel for banking and capital markets. Katherine Mulhern joins as a partner from Kaye Scholer, where she is a corporate partner in the London office. Roberto Bruno also joins as a partner from Cravath, Swaine & Moore's London office, where he is a senior attorney in the corporate department. Max Kirchner joins as senior counsel from the New York office of Latham & Watkins.