Mich. Comp. Laws § 252.309: Permit; issuance or denial.

Sec. 9.

Except for signs existing on March 31, 1972, a permit shall be issued or denied within 30 days after proper receipt of the permit form and the permit fee from the applicant. A permit shall not be issued for a sign which is prohibited by section 18(a), (b), (c), or (d). A permit shall not be issued for a sign that violates this act unless the sign is eligible for removal compensation under section 22.