Instytucja niesłusznego zbogacenia w polskim Kodeksie zobowiązań z 1933 r. na tle współczesnych kodyfikacji

The paper discusses the unjust enrichmennt as found in the Polish Code of Obligations of 1933. The discussion is conducted in a comparative way and makes allusions to other regulations of the time (those detectable in the ABGB, Code Civil, BGB, Obligationenrecht). It also makes reference to the solution accepted in the Polish Civil Code of 1964. What was discussed was the very construction of unjust enrichment as found in the aforementioned regulations (1), grounds for the claims (2), the scope within which the duty to return the enrichment applied (3), the nature of the claim – whether it was autonomous or subsidiary (4). In his final remarks, the author tried to assess the discussed institution as regulated in the Code of Obligations (5).