What is unjust enrichment (ongerechtvaardigde verrijking) under Dutch law?

Dutch term: Ongerechtvaardigde verrijking | Legal basis: Article 6:212 BW

Unjust enrichment (ongerechtvaardigde verrijking) under article 6:212 of the Dutch Civil Code creates a claim for compensation when one party has been enriched at the expense of another without legal justification. The enriched party must compensate the impoverished party to the extent that this is reasonable.

The claim requires: enrichment of one party, impoverishment of another, a connection between the two, and the absence of legal justification. The compensation is limited to the lesser of the enrichment and the impoverishment. Unjust enrichment is a residual claim: it is available only where no other legal basis (contract, tort) provides a remedy.

Why it matters for international businesses

In commercial practice, unjust enrichment claims arise when contractual arrangements fail (void contracts, invalid assignments) and one party has received a benefit that it cannot legally retain.