What to Know About Drafting Patent Claims

“When drafting a patent application, it is good practice to spend time drafting quality claims. Do not simply rely upon your ability to add claims later, because invariably you will want to at some point add claims that are not described in the specification.”

patent claims - https://depositphotos.com/152773296/stock-photo-table-with-poster-concept.htmlIn order to obtain exclusive rights on an invention, you must file for and obtain a patent. Many inventors will initially opt to file a provisional patent application to initiate the application process, which is a perfectly reasonable decision to make, and will result in a “patent pending” that can even result in a licensing deal. Ultimately, if a patent is desired, a nonprovisional patent application must be filed, and it is this nonprovisional patent application that will mature into an issued patent.

U.S. patent laws require that the patent applicant particularly point out and distinctly claim the subject matter which the inventor regards as his or her invention. Any patent, or patent application, contains a variety of different sections that contain different information. Generally speaking, a patent is divided into a specification, drawings and patent claims. Only the patent claims define the exclusive right granted to the patent applicant; the rest of the patent is there to facilitate understanding of the claimed invention. Therefore, patent claims are in many respects the most important part of the patent application because it is the claims that define the invention for which the Patent Office has granted protection.

When a nonprovisional patent application is filed a patent examiner will review the application to determine whether a patent can be allowed. The patent examiner does not review the entire patent application and does not evaluate the invention described in the patent application. Instead, the patent examiner will spend his or her time evaluating the patent claims submitted in order to determine whether the claimed invention is patent eligible, useful, novel and non-obvious. Generally speaking, for most inventions outside of the computer software and life sciences arena, patent eligibility is not an issue. Usefulness is also not generally problematic. Thus, patent examiners tend to focus their time on whether the claimed invention is novel and non-obvious.

35 USC 112 is the statutory requirement for applicants to particularly point out and distinctly claim the subject matter regarded as the invention. Like most statutes, Title 35 is not very specific with respect to the details regarding implementation of its directives. If you read the statute you will notice that 35 USC 112 only states that a claim is necessary, but the statute does not provide any information on the structure or format of the claim or claims submitted by the applicant. It is, therefore, necessary to turn to Title 37 of the Code of Federal Regulations (CFR), promulgated by the United States Patent and Trademark Office, to expand upon what is actually and formalistically required. The basic section that deals with claim requirements is 37 CFR 1.75.

Original Claims

It is necessary to include a full and complete description of the invention in the initial filing with the Patent Office. Rearranging of an application is always allowed, but the addition of new material is never allowed. In determining the breadth of what is covered by the initial filing, the applicant may rely on the description contained in the specification, any drawings present at the time of filing, as well as the originally filed claims.

Today, as the result of the Patent Law Treaty Implementation Act, patent claims and drawings are no longer required in order to obtain a filing date on a nonprovisional patent application. While patent claims can always be added to an application if the original disclosure as filed will support the claims, it is exceptionally dangerous to file a patent application without drawings. Drawings are almost always required and adding drawings later will be difficult if not completely impossible because drawings invariably convey more than the textual description of the drawings.

It is realistically essential to file any nonprovisional patent application with drawings, and advisable to file a nonprovisional patent applications with claims. Those claims filed with a nonprovisional patent application are original claims. These original claims can support themselves, meaning those claims that arrive in a patent application at the time the application is filed are considered a part of the larger, overall disclosure. Having claims present at the time of filing helps ensure that at least what you are claiming has sufficiently been disclosed in the patent application at the time of filing.

Originally filed claims need not be exhaustive. Throughout prosecution, patent claims can be amended and even added, provided of course the initial disclosure is broad enough to cover the added or amended matter. Therefore, when drafting a patent application, it is good practice to spend time drafting quality claims. Do not simply rely upon your ability to add claims later because invariably you will want to at some point add claims—or elements thereof—that are not described in the specification. Include enough claims with the initial filing to cover the invention and important variations.


Form of Claims 

The claim or claims filed in a nonprovisional patent application must commence on a separate sheet and should appear after the detailed description of the invention. While there is no set statutory form for claims, the present practice in the Patent Office is to insist that each claim must be the object of a sentence starting with “I claim,” “The invention claimed is”, or the substantial equivalent thereof.  This is accomplished by stating at the top of a clean sheet of paper after the detailed description: “I claim:” or “The invention claimed is:”. Notice the colon, which is important because each claim must contain this preliminary phrase. Having the statement present with a colon followed by a series of numbered claims will result in each claim starting with the required “I claim” (or equivalent) statement.

Each claim must be a single sentence, so each claim must begin with a capital letter and end with a period. This is true regardless of how tortured the sentence structure is and how incomprehensible the sentence may be to those not trained in patent claim drafting. Where a claim sets forth a plurality of elements or steps, each element or step of the claim can be separated by a line indentation. Because of the “one sentence” rule patent claims also tend to make heavy use of commas and semicolons. Abbreviations may be used but are not best practice and should be avoided because of the risk of ambiguity.

Reference characters corresponding to elements recited in the detailed description and the drawings may be used in conjunction with the recitation of the same element or group of elements in the claims. The reference characters, however, should be enclosed within parentheses so as to avoid confusion with other numbers or characters which may appear in the claims.

Claim Arrangement and Numbering

Claims should preferably be arranged in order of scope so that the first claim presented is the broadest (i.e., least restrictive). All dependent claims should be grouped together with the claim or claims to which they refer to the extent practicable. Similarly, product and process claims should be separately grouped. Such arrangements are for the purpose of facilitating classification and examination. Failure to arrange claims in the desired sequence is not fatal. The examiner who sees an inappropriate arrangement may issue an objection, although today this type of objection is rather rare. Objections are issued as to form and do not relate to the substantive patentability requirements. See

The refusal to grant claims because the subject matter as claimed is considered unpatentable is called a “rejection.” If the form of the claim (as distinguished from its substance) is improper, an “objection” is made. The practical difference between a rejection and an objection is that a rejection, involving the merits of the claim, is subject to review by the Patent Trial and Appeals Board, while an objection, if persistent, may be reviewed only by way of petition to the Commissioner. If the rejection and objection are for the same reason, an appeal can be taken to the Board. Objections vs. Rejections.


Independent vs. Dependent Claims

An independent claim is a stand-alone claim that contains a preamble and all of the elements necessary to define the invention.

37 CFR 1.75(c) explains that one or more claims may be presented in dependent form, referring back to and further limiting another claim or claims in the same application. Claims that refer back to and further limit another claim are called dependent claims. Dependent claims incorporate by reference each of the limitations of the claim from which they depend. Because dependent claims incorporate by reference each of the limitations of the claims from which they depend they are easy to write. Additionally, dependent claims are used in every application because additional fees are charged by the Patent Office if the application has more than three independent claims. Most patent applications have few independent claims and many dependent claims.

It is important to remember that dependent claims must further limit the claim from which they depend. This is most frequently accomplished by claiming a narrower range (where appropriate) or by the addition of one or more elements or characteristics. Claims written in dependent form that broaden the scope of the claim from which they depend are considered to be in improper dependent form.

For additional tips, including claim examples, read here.


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Join the Discussion

3 comments so far.

  • [Avatar for Ken Foster]
    Ken Foster
    October 5, 2019 11:04 am

    I so enjoy learning from Gene Quinn and his excellent Blogs. This one especially rang true to me. Thanks to years of training from various IP attorneys I’ve worked with as individual contributor and leader of new product development groups I can say this is a great example of best practices. Get the provisional written in a form that is almost as good as a full non-provisional application then continue the development. Stay tight communication with your I attorney. Excellent blog again!

  • [Avatar for Ken Starr]
    Ken Starr
    September 28, 2019 08:52 pm

    Big corporations have killed patents, until they drain out the swamp, filing for a patent in America is pointless.

  • [Avatar for Pass on the Application]
    Pass on the Application
    September 28, 2019 06:24 pm

    Pointless information, who in their right mind would file for a patent in the U.S.? The guy that invented 4G LTE can not get Apple to pay for the patents they stole and made billions off of his IP. My advise keep your invention private or team up with a major corporation in Germany.