Section 809.13. Rule (Intervention).

  A person who is not a party to an appeal may file in the court of appeals a petition to intervene in the appeal. A party may file a response to the petition within 11 days after service of the petition. The court may grant the petition upon a showing that the petitioner's interest meets the requirements of s. 803.09 (1) or (2) .

Sup. Ct. Order, 83 Wis. 2d xiii (1978); 1981 c. 390 s. 252 ; Sup. Ct. Order No. 00-02 , 2001 WI 39, 242 Wis. 2d xxvii. Judicial Council Committee's Note, 1978: Former s. 817.12 (6) permitted the addition of parties but did not set the criteria for doing so. This void is filled by making the intervention rule in the Rules of Civil Procedure applicable to proceedings in the Court of Appeals. [Re Order effective July 1, 1978] Judicial Council Note, 2001: The 7-day time limit has been changed to 11 days. Please see the comment to s. 808.07 (6) concerning time limits. [Re Order No. 00-02 effective July 1, 2001] A party who could have, but failed to, file a timely notice of appeal may not participate in the appeal as an intervenor or by filing a non-party brief. Weina v. Atlantic Mutual Insurance Co. 177 Wis. 2d 341 , 501 N.W.2d 465 (Ct. App. 1993). A non-party to a circuit court action may intervene in an appeal brought by another party, even after the time for filing a notice of appeal has passed. City of Madison v. WERC, 2000 WI 39 , 234 Wis. 2d 550 , 610 N.W.2d 94 , 99-0500 .