Mich. Comp. Laws § 339.733: Statements, records, schedules, working papers, or memoranda; restriction; sale, transfer, bequeathing, or assignment.

Sec. 733.

Statements, records, schedules, working papers, or memoranda made by a licensee or by an employee of a licensee shall remain the property of the licensee unless there is an agreement to the contrary. This subsection does not apply to a report submitted by a licensee to a client or a document constituting the original books or records of a client's business.

Statements, records, schedules, working papers, or memoranda pertaining to a client shall not be sold, transferred, or bequeathed without consent of the client or the client's personal representative and shall not be assigned except to 1 or more surviving partners or a new partner of the licensee or members of the licensee's firm.