Wis. Stat. § 221.0701: Interest exchange.

A bank or other corporation may acquire all of the outstanding shares of one or more classes or series of a bank organized under this chapter, with the approval of the division, if the board of directors of the bank, by resolution adopted by the board, approves a plan of interest exchange and its shareholders also approve a plan of interest exchange. This section does not limit the power of a corporation or bank to acquire all or part of the shares of one or more classes or series of a bank through a voluntary exchange or otherwise. Application for approval of an interest exchange shall be made to the division on a form prescribed by the division. The application shall be accompanied by a fee established by the division.