Wis. Stat. § 858.01
Except as provided by s. 865.11, the personal representative, within a reasonable time but no later than 6 months after appointment unless the court has by order extended or shortened the time, shall file an inventory of all property owned by the decedent. The inventory when filed shall show, as of the date of the decedent's death, the value of all property, what property is marital property and the type and amount of any existing obligation relating to any item of property. If a special administrator or personal representative has filed an inventory, no personal representative who is later appointed need file a further inventory unless additional property is found or the court orders otherwise.
Wis. Stat. § 858.01
See notes in 1985 Wis. Act 37, marital property trailer bill.