Definition : Unjust (unjustified) enrichment 

An act by which one person enriches himself at the expense of another without this enrichment being justified. The Civil Code of Quebec recognizes that a person who has fulfilled an obligation without reason and who has thus become impoverished may ask to be reimbursed by a person who has enriched himself to his detriment. Thus, no one can enrich himself at the expense of others.
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