Wis. Stat. § 703.21: Separate taxation.

(1) Every unit and its percentage of undivided interest in the common elements shall be deemed to be a parcel and shall be subject to separate assessments and taxation by each assessing unit and special district for all types of taxes authorized by law including, but not limited to, special levies based on the value of property and special assessments. Neither the building, the property nor any of the common elements shall be deemed to be a parcel separate from the unit.

(2) The rights, duties and obligations of unit owners under this chapter shall inure to and be binding upon grantees under tax deeds and persons acquiring title by foreclosure of tax liens and their successors in interest.