Minn. Stat. § 221.67: SERVICE OF PROCESS.

The use of any of the public highways of this state for the transportation of persons or property for compensation by a motor carrier in interstate commerce shall be deemed an irrevocable appointment by the carrier of the secretary of state to be the carrier's true and lawful attorney upon whom may be served all legal process in any action or proceeding brought under this chapter against the carrier or the carrier's executor, administrator, personal representative, heirs, successors or assigns. This use is a signification of agreement by the interstate motor carrier that any process in any action against the carrier or the carrier's executor, administrator, personal representative, heirs, successors, or assigns which is so served shall be of the same legal force and validity as if served upon the carrier personally. Service shall be made according to section 5.25 and the plaintiff's affidavit of compliance with the provisions of this section and sections 221.60, 221.65, and 221.68 must be attached to the summons.