Mich. Comp. Laws § 500.402c: Motor vehicle rental company; insurance transaction; definitions.

Sec. 402c.

A certificate of authority to transact insurance in this state is not required for the sale of any travel or auto-related insurance coverages by a motor vehicle rental company or its officers or employees in connection with and incidental to the rental of a motor vehicle.

As used in this section:

"Motor vehicle" means a motorized vehicle designed for transporting passengers or goods.

"Motor vehicle rental company" means any person in the business of providing motor vehicles to the public under a rental agreement for a period not to exceed 90 days.