Wis. Stat. § 632.37: Motor vehicle glass repair practices; restriction on specifying vendor.

An insurer that issues a motor vehicle insurance policy covering the repair or replacement of motor vehicle glass may not require, as a condition of that coverage, that an insured, or a 3rd party, making a claim under the policy for the repair or replacement of motor vehicle glass obtain services or parts from a particular vendor, or in a particular location, specified by the insurer.