Mich. Comp. Laws § 565.282: Validation of acknowledgments.

Sec. 2.

Any acknowledgment of any married woman to a deed of conveyance or other instrument affecting real property taken since the fourth day of August, A.D. 1875, in the same manner as if such married woman had been sole, is hereby declared valid and effectual for all intents and purposes, and shall be so held in all courts and places.