Wis. Stat. § 221.0205: Capital stock.

Immediately following a bank’s organization under this chapter, the division shall determine the required capital of the bank, subject to review by the banking institutions review board. In addition to the required capital stock, a contingent fund and paid-in surplus each in an amount equal to at least 25 percent of the aggregate amount of the capital stock, shall be subscribed at the time the subscription list of shareholders is prepared by the incorporators.