Wis. Stat. § 221.1201: Stock in bank-owned banks.

A bank, or, subject to the limitations of s. 221.0901, a bank holding company, may, with the approval of the division, acquire and hold stock, in an aggregate amount not exceeding 10 percent of its capital, in one or more of the following:

(1) A bank chartered under s. 221.1202.

(2) A national bank chartered under 12 USC 27 (b).

(3) A bank holding company wholly owning a bank described under sub. (1) or (2).