Wis. Stat. § 214.09: Acquisitions.

Subject to rules of the division, a savings bank holding company may acquire control of a savings bank or of a savings bank holding company upon application to and with the prior written approval of the division. The application shall be in a form prescribed by the division. The division shall approve the application if the division determines that the acquisition is consistent with the interest of maintaining a sound financial system and that the proposed acquisition does not afford a basis for supervisory objection.