Wisconsin Statutes Property (Ch. 700 to 710) § 706.06. Authentication

(1) Any instrument may be acknowledged, or its execution otherwise authenticated by its signators, as provided by the laws of this state; or as provided in this section or ch. 140.

(2) Any public officer entitled by virtue of his or her office to administer oaths, and any member in good standing of the State Bar of Wisconsin, may authenticate one or more of the signatures on an instrument relating to lands in this state, by endorsing the instrument “Acknowledged,” “Authenticated,” or “Signatures Guaranteed,” or other words to similar effect, adding the date of authentication, his or her own signature, and his or her official or professional title.The endorsement, unless expressly limited, shall operate as an authentication of all signatures on the instrument; and shall constitute a certification that each authenticated signature is the genuine signature of the person represented; and, as to signatures made in a representative capacity, shall constitute a certification that the signer purported, and was believed, to be such representative.

(3) Affidavits shall be authenticated by a certificate of due execution of the instrument, executed by a person entitled to administer oaths.

(4) In addition to any criminal penalty or civil remedy otherwise provided by law, knowingly false authentication of an instrument shall subject the authenticator to liability in tort for compensatory and punitive damages caused thereby to any person.