Complex sentence: Headquartered on Wall Street, Brown Brothers Harriman started with nine partners and about 200 employees, performing specialized banking services for customers, mainly medium-sized corporations; it was not a member of the Federal Reserve System or the Federal Deposit Insurance Corporation.
Split into simpler sentences: Headquartered on Wall Street, Brown Brothers Harriman started with nine partners and about two hundred employees. The firm performed specialized banking services for customers, mainly medium-sized corporations; it was not a member of the Federal Reserve System or the Federal Deposit Insurance Corporation.