One of the most important issues in transaction law is the role of formalities in them. Today, according to the principle of sovereignty of the will, it is stated that the principle is on the consent in contracts, but this article seeks to show that In the transactions of immovable property and intellectual (industrial) property that contain the transfer of objective rights, the legislator considers it necessary to perform formalities in the transaction, considering the higher interests, especially the protection of the rights of third parties, and guaranteeing the implementation of non-compliance with this requirement. It is different depending on the opinion of the legislator (but mostly it is either the invalidity of the legal act or the inability to cite). According to the investigations carried out in different cases in Iranian law, the research briefly concluded that in transactions regarding the transfer of objective rights in immovable property and intellectual (industrial) property, their registration is mandatory and in some cases the legislator went further and considered notification as necessary. The exception to this rule is the transfer of movable property, where, due to the merger of ownership and possession, the loss does not go to third parties. However, even in this case, sometimes the legislator considers the formalities to be necessary, such as the transfer of a car. However, in subjective rights and transfer cases, the rule is the consent of the contractor. Because the subjective right is a relative right and can only be invoked against others, not applicable in such a way as to expose their legal position to be disturbed.