The Impact of Behavior of Contracting Parties on Iranian Law and European Principles of International Contracts and Documents

Basically, after the conclusion of the contract, which can sometimes be very long, is the stage of implementation and fulfillment of mutual obligations, which arises in the first place from the authorized intention of the parties, which is based on the principle of freedom of contract and is manifested in the contract documents. Although the parties state their claims in the contract documents according to the principle of freedom of contract, these freedoms are subject to legal restrictions. On the other hand, the behavior of the parties to the contract is very important in how to fulfill the mutual obligations contained in the written documents of the contract. But it has not been widely cited in British courts. It should be noted that in all legal systems based on the rule of will of the parties in contracts, the subsequent behavior of the parties is considered the source of interpretation of the contract. Therefore, in Iranian law, despite the lack of specification, it can be accepted that by fulfilling the above conditions, the subsequent behavior of the parties in interpreting the contract can be cited. In the Convention on Sale and International Documents under study, despite the disagreement, it is accepted that the subsequent behavior of the parties can resolve the ambiguities in the contract, and explicitly the subsequent actions and behavior of the parties in interpreting the contract and clearing the ambiguity is considered.