Michigan Compiled Laws, Chapter 445. Trade and Commerce § 445.774a

Sec. 4a. (1) An employer may obtain from an employee an agreement or covenant which protects an employer's reasonable competitive business interests and expressly prohibits an employee from engaging in employment or a line of business after termination of employment if the agreement or covenant is reasonable as to its duration, geographical area, and the type of employment or line of business. To the extent any such agreement or covenant is found to be unreasonable in any respect, a court may limit the agreement to render it reasonable in light of the circumstances in which it was made and specifically enforce the agreement as limited.

(2) This section shall apply to covenants and agreements which are entered into after March 29, 1985.