Quasi-contract

In common law jurisdictions, the law of quasi-contract can be traced to the medieval form of action known as indebitatus assumpsit. In essence, the plaintiff would recover a money sum from the defendant as if the defendant had promised to pay it: that is, as if there were a contract subsisting between the parties. The defendant's promise - her agreement to be bound by the "contract" - was implied by law. The law of quasi-contract was generally used to enforce restitutionary

A quasi-contract was distinct from a contract implied in fact.

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