R2d § 177
When Undue Influence Makes a Contract Voidable
(1) Undue influence is unfair persuasion of a party who is under the domination of the person exercising the persuasion or who by virtue of the relation between them is justified in assuming that that person will not act in a manner inconsistent with his welfare. (2) If a party's manifestation of assent is induced by undue influence by the other party, the contract is voidable by the victim. (3) If a party's manifestation of assent is induced by one who is not a party to the transaction, the contract is voidable by the victim unless the other party to the transaction in good faith and without reason to know of the undue influence either gives value or relies materially on the transaction.
Professor's notes
Elements: (1) undue influence is unfair persuasion of a party who is under the domination of the person exercising the persuasion or who, by virtue of the relation between them, is justified in assuming that that person will not act in a manner inconsistent with his welfare; (2) if a party's manifestation of assent is induced by undue influence by the other, the contract is voidable by the victim.
Quebodeaux v. Quebodeaux operationalizes: intra-family transfer where a dominant party's influence overbore the weaker party's volition.
Common misunderstanding: students confuse undue influence with duress. Duress requires an improper threat (§ 175). Undue influence requires a confidential or dominant relationship plus unfair persuasion: no threat necessary. The doctrine reaches family, fiduciary, and trust-based contexts where pressure works through relationship rather than fear.
Cases that operationalize this rule
Text
R2d § 177. When Undue Influence Makes a Contract Voidable.
(1) Undue influence is unfair persuasion of a party who is under the domination of the person exercising the persuasion or who by virtue of the relation between them is justified in assuming that that person will not act in a manner inconsistent with his welfare.
(2) If a party’s manifestation of assent is induced by undue influence by the other party, the contract is voidable by the victim.
(3) If a party’s manifestation of assent is induced by one who is not a party to the transaction, the contract is voidable by the victim unless the other party to the transaction in good faith and without reason to know of the undue influence either gives value or relies materially on the transaction.