Writing Patent Specification

A well drafted application decides the fate of an invention. Drafting plays a vital role in the success of an invention during its prosecution, management and maintenance during its tenure and turning it into cash. Drafting a patent application is one of the most important and at the same time one of the most difficult process.


A Patent Specification has several sections and seems more complicated unless you understand the basic structure of a patent application. Some of the basic structures are reproduced below:

Indian Patent Office (IPO)

A typical patent specification has the following sections:

1. Title of invention;

2. Field of invention;

3. Background of invention with regard to the drawback associated with known art;

4. Object of invention;

5. Statement of invention;

6. A summary of invention;

7. A brief description of the accompanying drawing;

8. Detailed description of the invention with reference to drawing/examples;

9. Claim(s); and

10. Abstract.


Title of invention should reflect the main art of the invention. It should be precise, meaningful and should be normally within 15 words. A title can be used for more than one invention.


Field of invention should describe the scope of the invention and subject matter of the invention on which it relates. Basically, it should be crisp and clear enough so that the Examiner of patent easily understands the nature of the invention and classifies the technology according to its genera.


This section describes the state of the art in the particular technical area to which the patent relates and what problems remain to be solved or disadvantages accompanying the prior art solutions. In other words, Background of the invention should describe what others have done in the field, and what problems have not been solved by this prior work. It is always better to mention the status of the closest technology, experiments, patents and patent applications in this section.


Object of invention should clearly reflect the advantages of the invention. It should describe the solution of the existing technical problem associated with the existing field of art. Each and every object and advantages of the invention should be described in a separate sentence. Basically, this portion is a comparative analysis of the inventive technology over the existing one.


Statement of invention describes the exact novel features of the invention. It should clearly reflect the inventive feature of the invention over the existing one. This part is very useful to declare inventiveness of the invention and also relates exactly to the independent claims and to complement the omnibus claim in situations of infringement proceedings.


Summary of invention describes a broad overview of the invention and, thus, provide a structure for understanding the Detailed Description and Claim sections of the specification. The summary of the invention describes the invention overall, e.g., the purpose of the invention, problems solved, advantages offered, and so forth.


The brief description of drawings includes a written description of the invention that explains how to make and use it. It should point the reference numerals used in the drawings and should be specific. The details should be sufficient enough for a person skilled in the art to understand and perform the invention.


The detailed description describes in detail what the invention is and how it is made and used. Examples showing how the invention works in a particular application may or may not be present. It should reflect the complete picture of the invention and should be sufficient for a person skilled in the art to perform the invention by developing necessary technical know‐how.


Claims are the essence of a patent. The claims define the invention which the inventor holds as his exclusive property and has the right to exclude others from making, using and selling. The claims specify the scope of ownership in a piece of property, i.e. Intellectual Property. These claims are of paramount importance in both patent prosecution in the Patent Office and patent litigation in the courts. Therefore, during claim drafting the choice of words used in the patent claims should be dealt in a great understanding and thought.

Following points should be considered while drafting patent claims:

􀀹 Each claim should be a single sentence and should be clearly worded.

􀀹 Each claim should be precise and without unnecessary repetition.

􀀹 Rights are given to claims only, not for any matter described in the complete specification.

􀀹 Claims define the boundaries of legal protection and form a protective fence around the invention.

􀀹 Each claim is evaluated on its own merit and, therefore, if one of the claims is objected, it does not mean that the rest of the claims are invalid.

Tips on Drafting Claims

􀀹 Figure out the all essential features or elements of your invention that you want to claim rights to.

􀀹 Start with broadest claims of your invention and then progress to narrower claims.

􀀹 Start claims on a new page and number each claim using Arabic numbers starting with 1.

􀀹 Precede your claims with a short statement such as “I/We claim: …”

􀀹 Each claim should consist of an introduction, linking word, and body.

􀀹 The first claim would be the Independent claim and subsequent claim would be dependent claims. And, these claims should be linked so as to form a single inventive concept.

􀀹 There is no restriction to the number of claims to be incorporated in the specification. But the applicant has to pay additional fee, if there are more than ten claims.

􀀹 Claims must be supported by the description and should be based on the description. This means that all the characteristics of the invention that form the part of the claims must be fully explained in the description.