Montana Title 28. Contracts and Other Obligations § 28-2-407. What constitutes undue influence

(1) the use by one in whom a confidence is reposed by another person or who holds a real or apparent authority over the other person of the confidence or authority for the purpose of obtaining an unfair advantage over the other person;

(2) taking an unfair advantage of another person's weakness of mind; or

(3) taking a grossly oppressive and unfair advantage of another person's necessities or distress.