Wis. Stat. § 180.0304: Lack of corporate power.

(1) Except as provided in sub. (2), the validity of any corporate action or any conveyance or transfer of property to or by the corporation may not be challenged on the ground that the corporation lacks or lacked power to act.

(2) A corporation’s power to act may be challenged in any of the following proceedings:

(a) In a proceeding by a shareholder against the corporation to enjoin the act.

(b) In a proceeding by the corporation, directly, derivatively or through a receiver, trustee or other legal representative, against an incumbent or former director, officer, employee or agent of the corporation.

(c) In a proceeding by the attorney general under s. 180.1430 (1).

(3) In a shareholder’s proceeding under sub. (2) (a) to enjoin an unauthorized corporate act, the court may enjoin or set aside the act, if equitable and if all affected persons are parties to the proceeding, and the court may award damages for loss, other than loss of anticipated profits, suffered by the corporation or another party because of enjoining the unauthorized act.