Mich. Comp. Laws § 445.1660

Sec. 10. (1) A licensee or registrant may surrender a license or registration by delivering to the commissioner the license or registration with written notice that the licensee or registrant surrenders the license or registration. The surrender, revocation, or suspension of a license or registration under this act does not affect the licensee's or registrant's civil or criminal liability for acts committed before the surrender, revocation, or suspension. The surrender of a license or registration does not affect a proceeding to suspend or revoke a license or registration. (2) Except as otherwise provided by law, a revocation, suspension, or surrender of a license or registration does not impair or affect the obligation of a preexisting contract between the licensee or registrant and another person. (3) A licensee or registrant whose license or registration has been destroyed or lost may comply with this section by submitting to the commissioner a notarized affidavit of the loss accompanied by written notice that the licensee or registrant surrenders the license or registration.