Quantum meruit is an equitable remedy that is based upon the promise implied by law to pay for beneficial services rendered and knowingly accepted. The purpose of this common law doctrine is to prevent a party from being unjustly enriched by retaining the benefits of the performance without paying anything in return.

To recover under a quantum meruit claim, a claimant must prove that: (1) valuable services were rendered or materials furnished; (2) for the person sought to be charged; (3) those services and materials were accepted by the person sought to be charged, and were used and enjoyed by him; and (4) the person sought to be charged was reasonably notified that the plaintiff performing such services or furnishing such materials was expecting to be paid by the person sought to be charged.

Pleading In The Alternative

A party generally cannot recover under a quantum meruit claim when there is a valid contract covering the services or materials furnished. The measure of damages for recovery under a quantum meruit theory is the reasonable value of the work performed and the materials furnished.

But a party to a contract may seek alternative relief under both contract and quasi-contract theories. And pleading in the alternative does not defeat the effect of an arbitration clause that broadly covers all disputes between signatories that arise out of the underlying agreement.

In Missouri, quantum meruit is a legal doctrine that allows a party to recover the reasonable value of services or materials provided when there is no existing contract, or the contract is unenforceable. To succeed on a quantum meruit claim, the claimant must demonstrate that they provided valuable services or materials, the services or materials were accepted and used by the defendant, the defendant was aware that the claimant expected payment, and there was no valid contract covering the services or materials. However, if there is a valid contract, a quantum meruit claim typically cannot be pursued. Despite this, Missouri law allows for pleading in the alternative, meaning a party can seek recovery under both contract and quasi-contract theories, such as quantum meruit, without affecting the validity of an arbitration clause in the contract. This means that even if the parties have agreed to arbitrate disputes, a claimant may still plead a quantum meruit claim as an alternative to a breach of contract claim.