The Study of rights of obligee in any commercial contract, particularly contract of sale, is very important for the theoretical and practical reasons, in case that the other party performs part of contract only and is not able or ready to perform the other part; Because, on the one hand, the obligor wants to know whether he entitles to expect from the obligee to accept the executed part of contract and to terminate the breached part of that only; On the other hand, the obligee faces with these questions: what is his rights in this cases? Does he have to accept the executed and to terminate the breached part of contract only or entitles to terminate the whole of contract?
In this article the author tries to explain the rights of buyer and seller in these cases according to regulations of the Vienna Convention concerning International Sale of Goods (1980) and Iranian Law.
The result of this study proves that from the point of view of the Convention will be different the law of this case in that the contract is instalment or simple and whether the matter of contract is severable on the legal and physical reasons; however, it must be pretended that the apparent tendency of codificators of the Convention is the avoidance from the whole termination of contract for the partial breach, where as Iranian Law principally dose not allow the partial termination or the separation of contract.