If the essential purpose of a contract is frustrated, each party’s duty of performance is discharged, even if performance is not impossible.
A party’s principal reason for making the contract is substantially frustrated by a supervening event.
Non-occurrence of the event was a basic assumption upon which the contract was made.
The party did not expressly or impliedly assume the risk of the occurrence.
Frustration of purpose is included under the UCC § 2-615 provisions (see commercial impracticability, above).