USPTO Guidance for Claim Interpretation

Claims interpretation

The USPTO recently hosted a webinar about the general approach to interpreting claims and how the specification interacts with and modifies those claims. With the goal of providing answers to common examiner questions, the webinar specifically discussed the importance of the broadest reasonable interpretation (BRI) of each claim, how to handle claim limitations, and the added difficulty of limitations related to 35 USC 112(f) (aka “Means-or-Step-Plus-Function” Limitations). The hope is to create consistent examination guidance that ensures all claims will be interpreted similarly by anyone of ordinary skill in the art. 

Below is a summary of the key points of the USPTO's presentation.

Broadest Reasonable Interpretation (BRI)

The USPTO and the PTAB use the broadest reasonable interpretation (BRI) of claims because it ensures that patented claims will not be interpreted to include more than the examiner intended after the initial review. Reasonableness is measured by the specific words of the claims, the specification, and the knowledge of those of ordinary skill in the art.

When determining BRI, the USPTO recommends reviewing the entire application, including the claims, specification, and the drawings. Dictionary definitions alone are not sufficient for interpreting the claim language. Instead, they should be used to confirm terms of art or terms provided by the applicant and should be cited when relied upon. If there are any terms with an ambiguous meaning or if it is apparent that the applicant has a different view of the claim scope, the examiner should add written remarks to the office action to address the issue.

Reading limitations from the specification into the claims means that the BRI incorrectly limits the claims. Features in the specification that are not claimed should not be considered when constructing BRI.

Prior art can also be used to aid in the interpretation, but regardless of what is used to interpret the claims, it must be consistent with the way the terms are used in the original disclosure.

The same BRI must be used when evaluating the claim for compliance with the patentability statutes (§101, §112, §102, §103) and non-statutory double patenting.

Claim Limitations

All language that limits a claim must be considered, regardless of where it appears, but all such language must be read in context of the entire application.

A preamble can limit claims, but there is no clean-cut rule for when it will do so; it is a fact-specific determination. For example, a preamble that states a limitation on the structure of the invention would limit the claims, while a preamble that merely provides an intended use of the invention may not.

Wherein, whereby, and thereby clauses may also limit claims, so long as the language creates a patentable distinction. For example, language that limits the structure of the invention, requires steps to be performed, or states a material condition would limit the claims, while language that merely states the result of a limitation already recited in the claim may not.

Non-functional descriptive material (AKA “printed matter”), such as product labels and instructions should be considered when such material is functionally or structurally related to the invention. For example, printed matter that performs a function, such as volume markings on a measuring cup, should be given weight in interpreting the claims, while printed matter that merely serves as support for information, such as images on playing cards, should not.

In method claims, only steps that must be performed are considered in interpreting the claims, so contingent limitations should not be given any weight.


35 USC 112(f) Limitations (aka “Means-or-Step-Plus-Function” Limitations)

BRI still applies, even when a claim has a 112(f) limitation. 112(f) applies to limitations, not entire claims. The only difference in determining the BRI of a claim with a §112(f) limitation is that the meaning of the §112(f) limitation is controlled by the applicant’s specific disclosure of the structure that performs the claimed function, rather than plainly understood, commonly accepted meaning. Most 112(f) limitations are more narrowly defined as a result.

An applicant can argue for or against the application of 112(f) and can create a presumption that 112(f) is invoked by using the terms “means” or “step” (or conversely, a presumption that it is not invoked by not using those terms), but ultimately whether 112(f) is invoked is controlled by the claim language and whether the limitation meets the 3-prong test set forth in MPEP 2181.

If an examiner is having trouble determining if a claim limitation invokes §112(f) or how to treat a claim limitation that properly invokes §112(f), they can find helpful guidance here.

The USPTO encourages clear and early communication as to whether the examiner believes the claims invoke 112(f), so that any differences on the issue can be worked out at the beginning.

The USPTO is hoping to provide specific, easy-to-follow claim interpretation guidance for examiners in their application review process. Until that guidance is fully in effect, individual examiner analytics can provide insight into the best prosecution strategy for a difficult examiner. To see how Juristat Examiner Reports can benefit your practice, sign up for a demo today.

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