Mont. Code Ann. § 72-9-108

If the title to any property to which this part applies was held by the decedent at the time of death, title of the surviving spouse may be perfected by an order of the district court or by execution of an instrument by the personal representative or the heirs or devisees of the decedent with the approval of the district court. Neither the personal representative nor the district court in which the decedent's estate is being administered has a duty to discover or attempt to discover whether property held by the decedent is property to which this part applies, unless a written demand is made by the surviving spouse or the spouse's successor in interest.