"Actio de in rem verso"

Abstract

JURE naturae aequum est neminem cum alterius detrimento et injuria fieri locupletiorem is one of the few rules of natural law which pervade all legislations, notwithstanding that the legislator has not taken the trouble of formulating it expressely. It is, in fact, a fundamental principle of equity and, we may add, of law, that any advantage acquired without a legal title at the expense of others is to be returned by the person receiving it. As a sanction to this rule of equity the law grants an action against that person whose estate has been increased cum iniuria et alterius detrimento, which is called by modem writers action de in rem verso.