Meanings

"As much as he has deserved" or "reasonable value of services"

Situations

I. When a person employs (impliedly or expressly) another to do work for him, without any agreement as to his compensation, the law implies a promise from, the employer to the workman that he will pay him for his services, as much as be may deserve or merit.

II. When there is an express contract for a stipulated amount and mode of compensation for services, the plaintiff cannot abandon the contract and resort to an action for a quantum meruit on an implied assumpsit.

Examples

I. The famous example used in the nation’s law schools is usually as follows:

A Man (plaintiff in this hypothetical) talks to a neighbor (defendant) and tells him he's going to build a wall on their property that will give a benefit to both the man and his neighbor. The neighbor does not agree nor disagree with what the man wants to build. The man builds the wall, and then asks the neighbor to compensate him for the benefit of the wall that he conferred on the neighbor (usually half the value of the wall). The neighbor refuses. The man is entitled to some compensation based quantum meruit. This is because there was an implied promise between the man and the neighbor, which is derived from contract law, because the man was acting under the assumption that the neighbor would pay for part of his services. The plaintiff files suit in court on the basis of quantum meruit. The plaintiff makes an estimation of value conferred on the defendant, which the defendant has not paid. Plaintiff will likely win because of quantum meruit. The winning of the case will be directed as an assumpsit on a quantum meruit.

II. This is not the only factual scenario where this will work. Quantum meruit will also work where there is a breached contract.

A contractor is contracted to work on a school. Contractor does some work but messes up part of the work (breach of contract). School suspends the construction work because of the problem. Contractor is entitled to be paid for the services he has already done for the school on the basis of quantum meruit.