Wis. Stat. § 619.03: Voluntary risk-sharing plans.

Insurers doing business within this state are authorized to prepare voluntary plans providing any specified kind, line or class of insurance coverage or subdivision or combination thereof for all or any part of this state in which such insurance is not readily available in the voluntary market and in which the public interest requires the availability of such coverage. Voluntary risk-sharing plans shall be submitted to the commissioner and if approved may be put into operation.