Wis. Stat. § 891.05

Every patent which shall have been executed and delivered by the commissioners of school and university lands or by the commissioners of public lands, purporting to convey any land, and every deed or patent which shall have been executed and delivered by the governor, purporting to convey any lands granted to the state by the United States, shall be received as presumptive evidence of the facts therein stated and that the grantee named therein became vested thereby at the date thereof with an absolute title in fee to the lands therein described.