(Reuters) - State Street Corp said on Tuesday it would buy investment bank Brown Brothers Harriman & Co’s (BBH) investor services business for $3.5 billion in cash. The deal will include BBH’s custody, accounting, fund administration, global markets and technology services operations, State Street said. Reporting by Noor Zainab Hussain in Bengaluru; Editing by Vinay Dwivedi Our Standards: The Thomson Reuters Trust Principles.