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Broadest Reasonable Interpretation Unreasonably Broad?

October 31, 2017

In US patent law, during patent examination, claims are to be given the broadest reasonable interpretation (BRI) consistent the specification. A pair of recent decisions of the US Federal Circuit explored this principle in the context of inter partes review and ex parte re-examination proceedings.


Owens Corning v. Fast Felt Corp. 2016-2613 (Fed. Cir)

This was an appeal from an inter partes review (IPR) of the claims of U.S. Patent No. 8,137,757 (the ‘757 patent), which Fast Felt Corporation asserted against Owens Corning in an infringement action. The US Patent Trial and Appeal Board had concluded, upon review, that Owens Corning had failed to show obviousness of any of the challenged claims. The ‘757 patent relates to polymer “nail tabs” which are applied on “roofing and building cover material” to reinforce specific locations at which nails will be driven through the material to attach it to various surfaces. The ‘757 patent proposes an “automated” process to affix or bond “tab material that quickly solidifies and adheres or bonds” to a surface. The specification suggested that the surface to which the tab material is affixed can be “either dry felt, saturated felt, a fiberglass, polyester or other inorganic substrate roofing material whether or not coated with asphalt or an asphalt mix, or roll roofing material or shingles”. The preferred embodiments described in the patent focused on roofing materials that are or will be coated or saturated with asphalt or asphalt mix, although the claims were plainly not so limited.

In appealing the Board’s dismissal of its asserted ground of unpatentability for obviousness, Owens Corning argued that the Board adopted an erroneous claim construction. Specifically, it contended that the Board effectively treated “roofing or building cover material” as being limited to material that either has been or would be coated or saturated with asphalt or asphalt mix, and that such a construction is legally incorrect under the BRI standard. Indeed, the Board’s determination that a skilled person would not be motivated to combine the teachings of the prior art references under consideration in the IPR was predicated on the understanding of the claims as requiring materials that would eventually be coated with asphalt even if they had not already been coated before printing.

The Federal Circuit held that the Board erred in construing the claims to exclude such materials. The Court emphasized that the Board is to give a claim its broadest reasonable construction in light of the specification of the patent in which it appears. The focus on the preferred embodiments, i.e. roofing materials that are or will be coated or saturated with asphalt, does not narrow the claim scope in IPR. Furthermore, the specification was not limited to roofing materials and there was evidence that some building cover materials are commonly installed without any coating or saturation with asphalt or asphalt mixes. Accordingly, the Court concluded that a skilled person would be motivated to combine the prior art references to print nail tabs on building cover materials that are not asphalt coated or saturated.


In re Smith International, Inc. 2016-2303 (Fed. Cir)

Smith owns U.S. Patent No. 6,732,817 (the ‘817 patent) which is directed to a downhole drilling tool for oil and gas operations. The ‘817 patent was asserted in an infringement action against Baker Hughes Inc., and Baker Hughes had requested ex parte re-examination of the claims of the patent. The representative independent claim 28 recited an “expandable downhole tool for use in a drilling assembly” comprising “a body” and “at least one non-pivotable, movable arm… having angled surfaces that engage said body to prevent said arm from vibrating”. The US Patent Trial and Appeal Board affirmed the examiner’s rejection of claim 28 as being anticipated. The Board accepted the examiner’s interpretation of the term “body” as a generic term that encompasses the drilling tool’s internal components, reasoning that the term “body” was recited in the claims without further limiting features and that the specification did not proscribe a broad reading of the term. On appeal, Smith challenged the Board’s construction of “body”. In particular, Smith contended that “body” should be interpreted as an “outer housing” that is distinct from other separately identified components residing inside the drilling tool.

The Federal Circuit agreed with Smith and concluded that the Board’s construction of “body” was unreasonably broad. The Court noted that the specification does not use the term as a generic body, and instead consistently describes the body as a component distinct from others in the drilling tool. The BRI inquiry does not entail merely identifying whether the specification proscribes certain broad reading of the claim term adopted by the examiner. Instead, it is an interpretation “that corresponds with what and how the inventor describes his invention in the specification”. Accordingly, since the Board’s determination of anticipation relied on an incorrect claim construction, the Court held that the challenged claims of the ‘817 patent are not unpatentable as being anticipated or obvious in view of the prior art.


These cases bolster the principle that the broadest-reasonable-interpretation of patent claims must be grounded in the specification as a whole and cannot, in particular, proceed by reading limitations into a claim from the preferred embodiments described in the specification. Moreover, the lack of an express definition or disclaimer in the specification does not allow the PTAB or an examiner to adopt a broadest possible interpretation of a claim term. The principle of BRI emphasizes the importance of drafting to ensure that a patent specification provides sufficient and consistent support for the actual scope of protection (i.e. the different contemplated embodiments of an invention) sought in an application. 


Information in this article is for information only. It is not, and should not be taken as, legal advice. If you have any questions relating to the information in the above article or any intellectual property related matter, please contact our office and a Rowand LLP professional will be pleased to assist you.


Tags: patents