Michigan Compiled Laws, Chapter 500. Insurance Code of 1956 § 500.2608

Sec. 2608. (1) The commissioner shall review filings as soon as reasonably possible after they have been made in order to determine whether they meet the requirements of this chapter.

(2) Subject to the exception specified in subsection (3) of this section, each filing shall be on file for a waiting period of 15 days before it becomes effective, which period may be extended by the commissioner for an additional period not to exceed 15 days if he gives written notice within such waiting period to the insurer or rating organization which made the filing that he needs such additional time for the consideration of such filing. Upon written application by such insurer or rating organization, the commissioner may authorize a filing which he has reviewed to become effective before the expiration of the waiting period or any extension thereof. A filing shall be deemed to meet the requirements of this chapter unless disapproved by the commissioner within the waiting period or any extension thereof.

(3) Specific inland marine rates on risks specially rated by a rating organization shall become effective when filed and shall be deemed to meet the requirements of this chapter until such time as the commissioner reviews the filing and so long thereafter as the filing remains in effect.