Wis. Stat. § 221.0711: Duty to demand payment.

(1) Manner of demanding payment. A shareholder or beneficial shareholder who is sent a dissenters’ notice described in s. 221.0710, or a beneficial shareholder whose shares are held by a nominee who is sent a dissenters’ notice described in s. 221.0710, must demand payment in writing and certify whether he or she acquired beneficial ownership of the shares before the date specified in the dissenters’ notice under s. 221.0710 (2) (c). A shareholder or beneficial shareholder with certificated shares must also deposit his or her certificates in accordance with the terms of the notice.

(2) Effect of demand on holders of certificated shares. A shareholder or beneficial shareholder with certificated shares who demands payment and deposits his or her share certificates under sub. (1) retains all other rights of a shareholder or beneficial shareholder until these rights are canceled or modified by the effectuation of the corporate action.

(3) Effect of failure to demand. A shareholder or beneficial shareholder with certificated or uncertificated shares who does not demand payment by the date set in the dissenters’ notice, or a shareholder or beneficial shareholder with certificated shares who does not deposit his or her share certificates where required and by the date set in the dissenters’ notice, is not entitled to payment for his or her shares under ss. 221.0701 to 221.0718.