Montana Title 42. Adoption § 42-2-611. Irrevocable waiver of parental rights

(a) a putative father who was timely served with notice of intent to release if the court is provided with proof of service and proof that the putative father failed to timely comply with the requirements of the putative father registry;

(b) a parent or putative father who is served with notice of proceedings and fails to appear at the hearing; or

(c) a parent or putative father who is served with notice of proceedings and appears and denies any interest in custody of the child.