Mont. Code Ann. § 72-6-221
Authority of financial institution
72-6-221 . Authority of financial institution. A financial institution may enter into a contract of deposit for a multiple-party account to the same extent it may enter into a contract of deposit for a single-party account and may provide for a POD designation and an agency designation in either a single-party account or a multiple-party account. A financial institution need not inquire as to the source of a deposit to an account or as to the proposed application of a payment from an account.