See - January 2014 Philippine Supreme Court Decisions on Civil Law | LEXOTERICA: A PHILIPPINE BLAWG
"x x x.
Contracts; Principle of quantum merit; when allowed. -
Case law instructs that under this principle (quantum meruit), a contractor is allowed to recover the reasonable value of the thing or services rendered despite the lack of a written contract, in order to avoid unjust enrichment.
Quantum meruit means that, in an action for work and labor, payment shall be made in such amount as the plaintiff reasonably deserves.
The measure of recovery should relate to the reasonable value of the services performed because the principle aims to prevent undue enrichment based on the equitable postulate that it is unjust for a person to retain any benefit without paying for it.
- Rivelisa Realty, Inc., represented by Ricardo P. Venturina v. First Sta. Clara Builders Corporation, represented by Ramon A. Pangilinan, as President, G.R. No. 189618. January 15, 2014.
x x x."
