Quantum meruit

Quantum meruit is a Latin phrase meaning "what one has earned". In the context of contract law, it means something along the lines of "reasonable value of services".

In the United States, the elements of quantum meruit are determined by state common law. For example, to state a claim for unjust enrichment in New York, a plaintiff must allege that (1) defendant was enriched; (2) the enrichment was at plaintiff's expense; and (3) the circumstances were such that equity and good conscience require defendants to make restitution.

Quantum meruit is the measure of damages where an express contract is mutually modified by the implied agreement of the parties, or not completed. While there is often confusion between the concept of quantum meruit and that of "unjust enrichment" of one party at the expense of another, the two concepts are distinct.

The concept of quantum meruit applies in (but is not limited to) the following situations:

The measure of value set forth in a contract may be submitted to the court as evidence of the value of the improvements or services, but the court is not required to use the contract's terms when calculating a quantum meruit award. (This is because the values set forth in the contract are rebuttable, meaning the one who ultimately may have to pay the award can contest the value of services set in the contract.)

I. An example used in United States law schools is usually as follows:

II. Quantum meruit can also apply where there is a breached contract.

III. If a plaintiff is prohibited from completing work based on a long-term service contract where other contracts have been negotiated, the plaintiff may ask a court to determine a judgment based on the amounts that the defendant benefited. Third parties may also bring actions against the plaintiff.

IV. A promoter enters into a long-term service contract with a theatre to exclusively present events for a specified period. The promoter books events and contracts with others to perform during the entire period but alleges that the theatre is unsafe. The promoter withholds payments until the theatre is made safe. The theatre performs no repairs. Instead, the theatre terminates the entire service contract before the benefit of the events occurs to the plaintiff and refuses to repair the theatre. After the contract is terminated, the theatre operates the events negotiated by the promoter and gains a significant benefit but does not pay the promoter anything. The theatre also cancels some events without cause. A court determines that the promoter is entitled to an assumpsit on a quantum meruit.

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