Wis. Stat. § 553.73
When any person, including any nonresident of this state, engages in conduct prohibited or made actionable by this chapter or any rule or order under this chapter, whether or not the person has filed a consent to service of process under s. 553.27(10), and personal jurisdiction over the person cannot otherwise be obtained in this state, that conduct shall be considered equivalent to the person's appointment of the division to be the person's attorney to receive service of any lawful process in any noncriminal suit, action, or proceeding against the person or the person's successor or personal representative that grows out of that conduct and that is brought under this law or any rule or order under this chapter, with the same force and validity as if served on the person personally. Service may be made by leaving a copy of the process at the office of the division, but it is not effective unless the plaintiff, who may be the division in a suit, action, or proceeding instituted by the division, immediately sends notice of the service and a copy of the process by registered or certified mail to the defendant or respondent at his or her last-known address or takes other steps that are reasonably calculated to give actual notice, and the plaintiff's affidavit of compliance with this section is filed in the case on or before the return day of the process, if any, or within any further time that the court allows.
Wis. Stat. § 553.73