On November 6, 2017 the Minnesota Court of Appeals published an opinion reaffirming the common law principle that non-competes are valid only if they are included in the initial employment agreement or if the employer offers (and the employee accepts) additional consideration for such an agreement.
In this case (Safety Center v. Stier), the employee was given a written offer letter that said nothing about agreeing not to compete. She signed the acceptance letter and showed up for her first day of work a week later when she was then given the non-compete. She signed it, but because it wasn’t included in the initial offer from the employer and the employer offered no other consideration, the court held that it was invalid.