Wis. Stat. § 196.53: Franchise, foreign corporation not to have.

No license, permit or franchise to own, operate, manage or control any plant or equipment for the production, transmission, delivery or furnishing of heat, light, water or power may be granted or transferred to a foreign corporation. This section does not apply to an independent system operator, as defined in s. 196.485 (1) (d), or an independent transmission owner, as defined in s. 196.485 (1) (dm), that is approved by the applicable federal agency, as defined in s. 196.485 (1) (c), and that controls transmission facilities, as defined in s. 196.485 (1) (h), in this and another state.