This article hold to a comparative study in the three legal systems of European, French, American and Iranian concerning the obligation of warranty the hidden defects of products in the sale contracts. In the first instance to determinate the signification of defect and des sanctions foreseen in case of defect of product and finally the elimination of non-liability clauses in the same contract by referring the logic governing on the contract law and the Islamic regulation of Shariat.law, refund
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