The district courts of the United States and the United States courts of any Territory or other place subject to the jurisdiction of the United States shall have exclusive jurisdiction of violations of this chapter or the rules and regulations thereunder, and of all suits in equity and actions at law brought to enforce any liability or duty created by this chapter or the rules and regulations thereunder. Any criminal proceeding may be brought in the district wherein any act or transaction constituting the violation occurred. Any suit or action to enforce any liability or duty created by this chapter or rules and regulations thereunder, or to enjoin any violation of such chapter or rules and regulations, may be brought in any such district or in the district wherein the defendant is found or is an inhabitant or transacts business, and process in such cases may be served in any other district of which the defendant is an inhabitant or wherever the defendant may be found. In any action or proceeding instituted by the Commission under this chapter in a United States district court for any judicial district, a subpoena issued to compel the attendance of a witness or the production of documents or tangible things (or both) at a hearing or trial may be served at any place within the United States. Rule 45(c)(3)(A)(ii) of the Federal Rules of Civil Procedure shall not apply to a subpoena issued under the preceding sentence. Judgments and decrees so rendered shall be subject to review as provided in sections 1254, 1291, 1292, and 1294 of title 28. No costs shall be assessed for or against the Commission in any proceeding under this chapter brought by or against it in the Supreme Court or such other courts.