It's no secret what the favorite color is at Greenhill & Co. The investment bank specializes in mergers and acquisitions advisory, restructurings, and capital raising for corporate clients and governments around the globe. To avoid potential conflicts of interest and focus solely on the client, it does not engage in lending or capital markets services such as securities underwriting, research, and trading, unlike many of its rivals. Greenhill mainly advises companies in the industrial, consumer & retail, healthcare, and communications sectors. Its top clients include Arconic, AT&T, GlaxoSmithKline, London Stock Exchange, Tesco, Visa, and Wells Fargo, among others.