Mich. Comp. Laws § 125.1634a

Sec. 34a. (1) Notwithstanding any other provision of this act, a corporation for which a copy of articles of incorporation is on file with the secretary of state on or before the effective date of this section shall be deemed validly incorporated under this act from the date on which the articles of incorporation were filed, whether or not the articles of incorporation were adopted, executed, printed, certified, or filed in accordance with this act as in effect at the time of filing. (2) Any action taken by the corporation under this act, which at the time of the taking of the action the corporation would have been empowered to take, is deemed valid from the date the action was taken. (3) Any bond, note, or other evidence of indebtedness of any corporation and any instrument relating thereto authorized, issued, or delivered prior to the effective date of this section, is valid and legal for all purposes.