A claim for unjust enrichment may be brought by a party to recover the value of a benefit retained even absent any contractual relationship, if fairness and justice require it. Young v. Young, 164 Wn.2d 477, 484, 191 P.3d 1258 (2008).
Unjust enrichment requires proof of three elements:
(1) the defendant receives a benefit;
(2) the received benefit is at the plaintiff's expense; and
(3) the circumstances make it unjust for the defendant to retain the benefit without payment. Young v. Young, 164 Wn.2d at 484-85.
An unjust enrichment claim is founded on notions of justice and equity. Young v. Young, 164 Wn.2d at 486.