Wisconsin Statutes Property (Ch. 700 to 710) § 705.03. Ownership during lifetime

(1) A joint account belongs, during the lifetime of all parties, to the parties without regard to the proportion of their respective contributions to the sums on deposit and without regard to the number of signatures required for payment. The application of any sum withdrawn from a joint account by a party thereto shall not be subject to inquiry by any person, including any other party to the account and notwithstanding such other party's minority or other disability, except that the spouse of one of the parties may recover under s. 766.70. No financial institution is liable to the spouse of a married person who is a party to a joint account for any sum withdrawn by any party to the account unless the financial institution violates a court order.

(2) A P.O.D. account belongs to the original payee during the original payee's lifetime and not to the P.O.D. beneficiary or beneficiaries. If 2 or more parties are named as original payees, during their lifetimes rights as between them are governed by sub. (1); and a surviving original payee may revoke or amend the P.O.D. beneficiary designation at will.

(3) A marital account belongs, during the lifetime of both parties, to the parties without regard to the proportion of their respective contributions to the sums on deposit or to the number of signatures required for payment. A party to a marital account may name one or more P.O.D. beneficiaries for that party's interest. No person may inquire about the application of any sums withdrawn from a marital account by a party to the account, except that if the parties are married to one another the other party to the account may recover under s. 766.70.