Mont. Code Ann. § 42-2-208

When a putative father receives notice that a child in whom the putative father claims a parental interest is the subject of a termination of parental rights proceeding, the putative father must appear at the hearing held on the petition to terminate parental rights and demonstrate, at a minimum, that the criteria set out in 42-2-610 for determining whether the putative father has made reasonable efforts to establish a substantial relationship with the child who is the subject of the proceedings have been met.