What is the difference between structural and functional limitations in apparatus claims?
In apparatus claims, features can be recited either structurally or functionally. As stated in MPEP 2114: “Features of an apparatus may be recited either structurally or functionally. In re Schreiber, 128 F.3d 1473, 1478, 44 USPQ2d 1429, 1432 (Fed. Cir. 1997).” Structural limitations describe the physical components of the apparatus, while functional limitations describe what…
Read MoreHow can an applicant resolve ambiguities in functional limitations?
The MPEP provides several ways an applicant can resolve ambiguities in functional limitations during prosecution: Use a quantitative metric instead of a qualitative functional feature. For example, include a numeric limitation for a physical property. Demonstrate that the specification provides a formula for calculating a property, along with examples that meet and do not meet…
Read MoreWhat is the purpose of functional limitations in patent claims?
The purpose of functional limitations in patent claims is to define an element in terms of what it does rather than what it is. According to MPEP 2173.05(g), “A functional limitation is an attempt to define something by what it does, rather than by what it is (e.g., as evidenced by its specific structure or…
Read MoreHow does MPEP 2114 address computer-implemented functional claim limitations?
MPEP 2114 provides specific guidance on computer-implemented functional claim limitations. Key points include: For computer-implemented functional claim limitations, the specification must disclose an algorithm for performing the claimed function. If the specification does not provide a disclosure of the computer and algorithm in sufficient detail, a rejection under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C.…
Read MoreHow does the written description requirement relate to means-plus-function claim limitations?
Means-plus-function claim limitations have a special relationship with the written description requirement. According to MPEP 2163.03: “A claim limitation expressed in means- (or step-) plus-function language ‘shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.’ 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.” However,…
Read MoreWhat are the potential issues with functional limitations in patent claims?
While functional limitations are allowed in patent claims, they can potentially raise issues of indefiniteness. The MPEP notes that “the use of functional language in a claim may fail ‘to provide a clear-cut indication of the scope of the subject matter embraced by the claim’ and thus be indefinite.” Some potential issues include: Claims that…
Read MoreHow are computer-implemented functional claim limitations interpreted in patent examination?
Computer-implemented functional claim limitations are interpreted broadly in patent examination. According to MPEP 2114: “Functional claim language that is not limited to a specific structure covers all devices that are capable of performing the recited function.” This means that if a prior art device can inherently perform the claimed function, it may be grounds for…
Read MoreWhat is the difference between functional limitations and means-plus-function claim language?
While both functional limitations and means-plus-function claim language describe elements by their function, there are important differences: Means-plus-function claims are a specific form of functional claiming authorized by 35 U.S.C. 112(f). Means-plus-function claims are interpreted more narrowly, limited to the structure disclosed in the specification and its equivalents. General functional limitations can be broader and…
Read MoreAre functional limitations allowed in patent claims?
Yes, functional limitations are generally allowed in patent claims. The MPEP states, “There is nothing inherently wrong with defining some part of an invention in functional terms. Functional language does not, in and of itself, render a claim improper.” In fact, functional language can be used to limit claims without using the means-plus-function format. However,…
Read MoreWhat is a functional limitation in a patent claim?
A functional limitation in a patent claim is a term that recites a feature “by what it does rather than by what it is”. As stated in the MPEP, “A claim term is functional when it recites a feature ‘by what it does rather than by what it is’ (e.g., as evidenced by its specific…
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