quantum valebant n[Latin, as much as they were worth]
1 : a count in a common-law action of assumpsit to recover the value of goods or materials furnished
2 : a theory or doctrine that permits recovery for materials provided on the basis of an implied contract
Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.