12 C.F.R. § 263.457 – Subpoenas.

(a) Service. Service of a subpoena may be made:
1. (1) By personal service;
2. (2) If the person to be served is an individual, by delivery to a person of suitable age and discretion at the physical location where the individual resides or works;
3. (3) By delivery to an agent which, in the case of a corporation or other association, is delivery to an officer, director, managing or general agent, or to any other agent authorized by appointment or by law to receive service and, if the agent is one authorized by statute to receive service and the statute so requires, by also mailing a copy to the party;
4. (4) By registered or certified mail or by an express delivery service addressed to the person's or authorized agent's last known address; or
5. (5) In such other manner as is reasonably calculated to give actual notice.
(b) Area of service. Service in any state, territory, possession of the United States, or the District of Columbia, on any person or company doing business in any state, territory, possession of the United States, or the District of Columbia, or on any person as otherwise provided by law, is effective without regard to the place where the hearing or testimony is held, provided that if service is made on a foreign bank in connection with an action or proceeding involving one or more of its branches or agencies located in any state, territory, possession of the United States, or the District of Columbia, service must be made on at least one branch or agency so involved. Foreign nationals are subject to such subpoenas if such service is made upon a duly authorized agent located in the United States or such other means permissible by law.
(c) Witness fees and mileage. Witnesses summoned in any proceeding under this subpart must be paid the same fees and mileage that are paid witnesses in the district courts of the United States. Such fees and mileage need not be tendered when the subpoena is issued on behalf of the Board by any of its designated representatives.