(2 minutes) State Street Corp. agreed to buy Brown Brothers Harriman & Co.’s investor-services unit for $3.5 billion in cash, a deal that expands the custody bank’s core business serving … State Street acquires BBH Investor Services for $3.5bn - Citywire State Street Buys BBH Investor Services for $3.5B | FTF News state street buying bbh investor services State Street to pay $3.5bn BBH’s investor services business State Street has entered into a definitive agreement to buy investor services business of Brown Brothers Harriman & Co. (BBH) in a cash deal valued at $3.5bn. Securities finance industry news | State Street to acquire BBH