Mich. Comp. Laws § 600.5838b

Sec. 5838b. (1) An action for legal malpractice against an attorney-at-law or a law firm shall not be commenced after whichever of the following is earlier: (a) The expiration of the applicable period of limitations under this chapter. (b) Six years after the date of the act or omission that is the basis for the claim. (2) A legal malpractice action that is not commenced within the time prescribed by subsection (1) is barred. (3) As used in this section: (a) "Attorney-at-law" means an individual licensed to practice law in this state or elsewhere. (b) "Law firm" means a person that is primarily engaged in the practice of law, regardless of whether organized as a sole proprietorship, partnership, limited liability partnership, professional limited liability company, professional corporation, or other business entity. Law firm includes a legal services organization.