Nowadays, in the field of inventions, the importance of the claims in the declaration is not hidden from anyone. In other words, the beating heart of a patent application is the claims contained in a declaration. Despite the importance of the claims, the Law on Patents, Industrial Designs and Trademarks, approved in November 2007, does not define the claim. Also, the law does not specify rule about how a claim should be written in the declaration, how the claim should be interpreted, why the claim was written, whether or not the inventor should write the claim, and the types of claims and other issues. Therefore, it is necessary that the claim, the function and also the types of claims be ruled by the legislator. Therefore, in this article, with the Analytical and descriptive method an attempt has been made to study position of the claim and the subtleties of claim writing, which have a great impact on the acceptance or rejection of the patent application by the relevant experts, and in this way the importance of correct linguistic signs And choosing the right words can not be neglected. Therefore, it is suggested that in the draft proposal for the protection of industrial property, a part of the law be devoted to the subject of the claim and instead of the characteristics of the claim, the intrinsic elements of the claim be mentioned.