Mich. Comp. Laws § 500.1212

Sec. 1212. (1) An agent may not appoint, employ or in any manner receive the benefit of business done or services rendered in this state by a person acting as a solicitor unless that person is so authorized to act by a written contract with the agent, he is licensed as a solicitor in accordance with this chapter, and the agent has notified the commissioner in writing of the appointment. (2) A person who is licensed as a solicitor, within the lines of insurance permitted by the license, may act on behalf of a licensed agent if the agent has properly notified the commissioner of the appointment of that person as his solicitor.