Background and Purpose: In some cases, the occurrence of phenomena beyond the imagination and power of the parties makes the implementation of the contract impossible. In different legal systems, such a situation is justified by different institutions and theories. The purpose of this article is to investigate the effect of fundamental conditions in commercial contracts in Iranian jurisprudence and law and Canada law.
Materials and methods: This paper is descriptive and analytical method.
Ethical considerations: In this paper, the originality of the text, honesty, and trustworthiness are respected.
Results: The impossibility of executing a contract, which is described by the theory of frustration in Canada law, has many similarities with the rule "when the execution of an obligation is impossible, that obligation is void" in jurisprudence and force majeure in civil law. in Iranian law, the effects of this situation are more diverse, in such a way that depending on the subject, it may be forced dissolution or Voluntary liquidation or suspension and even the right to terminate.
Conclusion: The results showed Although the result of the impossibility of executing the contract ultimately provides the reasons for the obligee's exemption, but in terms of the basis and justification of the obligee's acquittal, the two systems have different bases. Despite some differences in the concepts and expressions, the results of the impossibility of contract execution in both systems based on the release and acquittal of the obligee are similar.