Evolution of Claim Interpretation under the BRI Test and Functional Claiming

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The Federal Circuit has provided patent applicants and owners with bolstered ammunition for use in establishing patentability and addressing functional claim terms. In the recent In re Smith decision, the Federal Circuit reversed a PTAB decision upholding an interpretation of claim terms that, while a “possible” interpretation, was deemed unreasonable in view of the specification. See In re Smith Int’l, Inc., Fed. Cir. No. 2016-2303 (September 26, 2017). This decision may provide patent applicants with a defense against claim rejections relying upon unsupported and overly-broad interpretations, and may provide patent litigants with a corresponding defense against invalidity.

In the In re Smith decision, the patent owner (Schlumberger) had sued a defendant (Baker Hughes) for infringement, and the defendant requested an ex parte reexamination. The claim term at issue was the word “body” as used in the context of a drilling tool for oil and gas operations. The body moves axially relative to a mandrel, which causes a cam sleeve to push cutters radially outward. The claims at issue did not include the mandrel or cam sleeve. Specifically, the claims recited a body defining an outermost diameter of the tool and at least one non-pivotable, moveable arm having a surface that engages the body, in which the body guides a direction of translation of the arm along surfaces of the arm and body. The Examiner had rejected the claim using an interpretation of the term “body” as encompassing various parts, including a “mandrel” and “cam sleeve.” The provided rationale was that the specification did not define the term body, and did not “prohibit” the Examiner’s reasoning.

The PTAB affirmed, finding that the term “body” was generic and without structural specificity, equating the term with other terms such as “member” or “element” that have recently been referred to as “nonce” terms in the context of functional claiming. Specifically, the Board reasoned that although “the specification describes the body as a discrete element separate from other elements,” the specification does not “define[ ] the term ‘body’” or “preclude the Examiner’s interpretation.” Board Decision, 2016 Pat. App. LEXIS 3764, at *4. (emphases in original). The Board also rejected the argument that a person of ordinary skill in the art would understand the term “body” as a distinct element from other components, reasoning that the patent owner had “not shown that the parts identified in the prior art as bodies are so similar as to create a specific identity of what a body is,” and further reasoning that the term “body” may include one or more other elements. Id. at *4–5. The PTO argued in support of the Board’s construction based on:

  1. the recitation of “a body” as a whole element in claim 28;
  2. a lack of recitation of “mandrel” in the claims;
  3. a lack of definition of “body” in the specification; and
  4. a lack of an established meaning of “body” in the art.

The PTO also urged that the proposed construction of the “body” as an “outer housing” is not supported by the specification.

The Federal Circuit reversed the PTAB’s decision, holding that the PTAB’s construction of the term “body” was unreasonably broad. The court reiterated that the appropriate test is whether the claims are given their broadest reasonable interpretation, not their broadest possible interpretation. Specifically, the court noted that the Board’s reliance upon “a broadest possible interpretation of a claim term, irrespective of repeated and consistent descriptions in the specification that indicate otherwise … is not properly giving the claim term its broadest reasonable interpretation in light of the specification (emphasis in original). See In re Smith Int’l, Inc., at 13. The court referenced description in the specification that described the body as a component distinct from the others, and held that the PTAB erred in concluding that the Examiner’s interpretation was reasonable (simply “because the specification does not ‘in and of itself proscribe the Examiner’s construction”). Id. at 12. The court further held that:

[t]he correct inquiry in giving a claim term its broadest reasonable interpretation in light of the specification is not whether the specification proscribes or precludes some broad reading of the claim term adopted by the examiner. And it is not simply an interpretation that is not inconsistent with the specification. It is an interpretation that corresponds with what and how the inventor describes his invention in the specification, i.e., an interpretation that is ‘consistent with the specification.’ In re Morris, 127 F.3d 1048, 1054 (Fed. Cir. 1997) (citation and internal quotation marks omitted); see also In re Suitco Surface, 603 F.3d 1255, 1259–60 (Fed. Cir. 2010). Id. at 12-13.

The court noted that the PTAB cannot construe the claims “so broadly that its constructions are unreasonable under general claim construction principles,” and that “the protocol of giving claims their broadest reasonable interpretation … does not include giving claims a legally incorrect interpretation … divorced from the specification and the record evidence.” Microsoft Corp. v. Proxyconn, Inc., 789 F.3d 1292, 1298 (Fed. Cir. 2015) (emphasis in original, citations and internal quotation marks omitted); See PPC Broadband, Inc. v. Corning Optical Commc’ns RF, LLC, 815 F.3d 747, 751–53 (Fed. Cir. 2016). The In re Smith decision thus elaborates upon long-standing law, which requires that an interpretation of claim terms must be consistent with the specification, and may assist the patent applicant or patentee in combating overly-broad claim interpretation.

The In re Smith decision also touches on the use of general terms such as “body” without corresponding structure, which may be argued as “nonce” terms as relative to functional claiming and a traditional means-plus-function interpretation. The court noted that description in the specification was important for providing an interpretation favorable to the patentee. Importantly, the decision suggests that, if the specification and/or claims had further defined the “body” with more particular structure, the issues would likely have been alleviated. For further information regarding U.S. Patent Law on interpreting claim terms which appear as generic structure, reference may be made to a recent article published by this firm, “Functional Claiming under U.S. Patent Law,” Eric Curtin, et al., International In-house Counsel Journal, Vol. 8, No. 32, Summer 2015, 1. This article provides various practical considerations for addressing challenges with functional terms and related structure. For instance, “[d]rafting patent claims that emphasize operations, steps and activities of structure can be beneficial,” and reciting “internal/inherent structure” with a claim term “may also usurp an interpretation under § 112(6/f).” Id.As applicable here, the Federal Circuit suggested that defining further structure would have assisted, possibly avoiding costly litigation.

The considerations presented herein can be helpful in patent drafting, prosecution and litigation. Contact Crawford Maunu for further discussion as to how these aspects may be important for your patent portfolio. You may find us on the web at

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