You can find financial institutions in
Appendix D of the BSA Exam Manual.
The list includes:
A broker or dealer in securities or commodities.
An investment banker or investment company.
The
Professional Service Provider section of the exam manual provides a description and examples:
A professional service provider acts as an intermediary between its client and the bank. Professional service providers include lawyers, accountants,
investment brokers, and other third parties that act as financial liaisons for their clients. These providers may conduct financial dealings for their clients. For example, an attorney may perform services for a client, or arrange for services to be performed on the client’s behalf, such as settlement of real estate transactions, asset transfers, management of client monies, investment services, and trust arrangements.