The Doctrine has defined unjust enrichment as:
«That case in which a person, as a result of a patrimonial displacement verified in accordance with the requirements demanded by a specific legal system, experiences an increase in his active patrimony at the expense of another person, but in such circumstances that conflict with the postulates of justice and equity crystallized in the positive order itself» (Álvarez Suarez).
Unjust enrichment is a figure of jurisprudential creation. Specifically, in the words of the Supreme Court, Civil Chamber (Section 1), Sentence no. 1016/2006 of October 6:
“In the absence of a general regulation of the figure of enrichment without cause in our legal system, jurisprudence supports it in the general principle of law that no one can unjustifiably enrich themselves at the expense of another by creating themselves, in case they have reached thus producing that benefit, the obligation to restore or repair the patrimony impoverished by those who, at their expense, have enriched theirs… This conception, which only requires a correlation between such impoverishment and enrichment, can be accommodated both in the direct relationship between both interested parties or through an indirect patrimonial attribution from the patrimonial situation of a third party”.
The necessary requirements for the application of unjust enrichment have been established by the Jurisprudence, in reiterated doctrine, contained for example in Sentence of the Supreme Court, Civil Chamber, of November 15, 1990, in the following terms :
“An already ancient and traditional Jurisprudence that was based on a well-known text from Las Partidas in which it was said that no one should enrich themselves tortiously in harm to another (7, 34, 17), has been insisting that The requirements that any claim to enrichment must meet are specified in the acquisition of a profit or patrimonial advantage by the defendant with the correlative impoverishment of the plaintiff, the proper connection between enrichment and impoverishment and the lack of cause that justifies said enrichment….”
The doctrine and jurisprudence end up reducing the issue to the existence or not in the case of a just cause of the patrimonial attribution in question, understanding as such the legal situation that, in accordance with the legal system, authorizes its beneficiary to receive and keep it.
In short, for the appreciation of the figure of unfair enrichment it is necessary:
- Production of an increase in the assets of the defendant.
- Correlative impoverishment of the plaintiff
- That no legal precept excludes the application of this general principle of law.
Clarify that it is not necessary to mediate bad faith on the part of any of the parties; the responsibility for unjust or unjust enrichment is not based on the existence of bad faith, but on the fact of having obtained an undue gain (This has been declared by the Supreme Court, Chamber Civil Law, for example in Judgment No. 1129/1994 of December 14).
Some examples of cases in which jurisprudence has understood the concurrence of unjust enrichment, or patrimonial transfer without just cause, are the following:
- The use and/or consumption of someone else’s thing without title: Therefore, the benefit or advantage obtained must be restored.
- Untitled employment in a professional activity: This assumption is related to the figure of the negotiorum gestio or the manager of other people’s businesses, having revealed our doctrine such as the management of other people’s businesses and the doctrine of unjust enrichment are found in bordering territories.
- The incorporation of profits into someone else’s thing. They are those cases in which the legal system does not recognize the validity of a patrimonial attribution when it is not based on business relationships or on principles of justice such as accession cases.
- Another case of unjust enrichment is payments without cause (or improper payments).
At this point it is necessary to make a brief reference to a legal figure intimately linked to unjust enrichment, the collection of what is undue.
Article 1895 of the Code Civil establishes that: “When something is received for which there was no right to collect, and which has been improperly delivered by mistake, the obligation to return it arises< em>.”
Regarding the requirements for the collection of what is improper, among others, the Supreme Court ruled in its judgment of November 21, 1957:
“The following are requirements for the action to repeat wrongdoing to succeed: 1º) Effective payment, made with the intention of extinguishing the debt (animus solvendi). 2º) Absence of obligation between the one who pays and the one who receives, and consequently lack of cause in the payment, which may be subjectively improper. 3º) Error on the part of the person who made the payment”
Part of the Doctrine comes to consider that collection of undue is a manifestation or principle that prohibits unjust enrichment.