USA
158 Relief Including Restitution see also Validity
1. In any case governed by the rules stated in this Chapter, either party may have a claim for relief including restitution under the rules stated in §§ 240 and 376.
2. In any case governed by the rules stated in this Chapter, if those rules together with the rules stated in Chapter 16 will not avoid injustice, the court may grant relief on such terms as justice requires including protection of the parties' reliance interests.
[Chapter 6 - Mistake]
197 Restitution Generally Unavailable see also Validity
Except as stated in §§ 198 and 199, a party has no claim in restitution for performance that he has rendered under or in return for a promise that is unenforceable on grounds of public policy unless denial of restitution would cause disproportionate forfeiture.
198 Restitution in Favor of Party Who Is Excusably Ignorant or Is Not Equally in the Wrong see also Validity
A party has a claim in restitution for performance that he has rendered under or in return for a promise that is unenforceable on grounds of public policy if
- he was excusably ignorant of the facts or of legislation of a minor character, in the absence of which the promise would be enforceable, or
- he was not equally in the wrong with the promisor.
199 Restitution Where Party Withdraws or Situation Is Contrary to Public Interest see also Validity
A party has a claim in restitution for performance that he has rendered under or in return for a promise that is unenforceable on grounds of public policy if he did not engage in serious misconduct and
- he withdraws from the transaction before the improper purpose has been achieved, or
- allowance of the claim would put an end to a continuing situation that is contrary to the public interest.
272 Relief Including Restitution see also Mandatory obligations Termination
1. In any case governed by the rules stated in this Chapter, either party may have a claim for relief including restitution under the rules stated In §§ 240 and 377.
2. In any case governed by the rules stated in this Chapter, if those rules together with the rules stated in Chapter 16 will not avoid injustice, the court may grant relief on such terms as justice requires including protection of the parties' reliance interests.
[Chapter 11 - Impracticability of Performance and Frustration of Purpose]
Topic 4 - Restitution
370 Requirement That Benefit Be Conferred
A party is entitled to restitution under the rules stated in this Restatement only to the extent that he has conferred a benefit on the other party by way of part performance or reliance.
371 Measure of Restitution Interest
If a sum of money is awarded to protect a party's restitution interest, it may as justice requires be measured by either
- the reasonable value to the other party of what he received in terms of what it would have cost him to obtain it from a person in the claimant's position, or
- the extent to which the other party's property has been increased in value or his other interests advanced.
372 Specific Restitution
1. Specific restitution will be granted to a party who is entitled to restitution, except that:
- specific restitution based on a breach by the other party under the rule stated in § 373 may be refused in the discretion of the court if it would unduly interfere with the certainty of title to land or otherwise cause injustice, and
- specific restitution in favor of the party in breach under the rule stated in § 374 will not be granted.
2. A decree of specific restitution may be made conditional on return of or compensation for anything that the party claiming restitution has received.
3. If specific restitution, with or without a sum of money, will be substantially as effective as restitution in money in putting the party claiming restitution in the position he was in before rendering any performance, the other party can discharge his duty by tendering such restitution before suit is brought and keeping his tender good.
373 Restitution When Other Party Is in Breach
1. Subject to the rule stated in Subsection (2), on a breach by non-performance that gives rise to a claim for damages for total breach or on a repudiation, the injured party is entitled to restitution for any benefit that he has conferred on the other party by way of part performance or reliance.
2. The injured party has no right to restitution if he has performed all of his duties under the contract and no performance by the other party remains due other than payment of a definite sum of money for that performance.
374 Restitution in Favor of Party in Breach
1. Subject to the rule stated in Subsection (2), if a party justifiably refuses to perform on the ground that his remaining duties of performance have been discharged by the other party's breach, the party in breach is entitled to restitution for any benefit that he has conferred by way of part performance or reliance in excess of the loss that he has caused by his own breach.
2. To the extent that, under the manifested assent of the parties, a party's performance is to be retained in the case of breach, that party is not entitled to restitution if the value of the performance as liquidated damages is reasonable in the light of the anticipated or actual loss caused by the breach and the difficulties of proof of loss. § 375 Restitution When Contract Is Within Statute of Frauds
A party who would otherwise have a claim in restitution under a contract is not barred from restitution for the reason that the contract is unenforceable by him because of the Statute of Frauds unless the Statute provides otherwise or its purpose would be frustrated by allowing restitution.
376 Restitution When Contract Is Voidable see also Validity
A party who has avoided a contract on the ground of lack of capacity, mistake, misrepresentation, duress, undue influence or abuse of a fiduciary relation is entitled to restitution for any benefit that he has conferred on the other party by way of part performance or reliance.
377 Restitution in Cases of Impracticability, Frustration, Non-Occurrence Of Condition or Disclaimer by Beneficiary
A party whose duty of performance does not arise or is discharged as a result of impracticability of performance, frustration of purpose, non-occurrence of a condition or disclaimer by a beneficiary is entitled to restitution for any benefit that he has conferred on the other party by way of part performance or reliance.

