The Kamstrup case at the CAFC

Kamstrup A/S appeals a final written decision of the Patent Trial and Appeal Board. The Board found claims 1–15 of Kamstrup’s U.S. Patent No. 8,806,957 unpatentable as obvious or anticipated. On appeal, Kamstrup challenges the Board’s claim constructions. In addition, Kamstrup challenges the Board’s anticipation and obviousness determinations largely on the basis that the Board erred in rejecting Kamstrup’s claim construction arguments. We affirm. Kamstrup owns U.S. Patent No. 8,806,957 (the “’957 patent”). The ’957 patent describes ultrasonic flow meters and housings. ’957 patent abstract. The specification discloses that the meters are used for “calculating a consumed quantity of water, heat, cooling, gas or the like.” Id. at 1:27–30. Ultrasonic flow meters include “housing” to protect electronic components, such as a display or battery. Id. at 1:32–38. The ’957 patent is directed to “an ultrasonic flow meter housing in the form of a monolithic polymer structure being cast in one piece.” Id. at 1:58–60. It explains that “the present invention can be fabricated with a reduced number of steps compared to existing meters, since only a single step is used to form the monolithic polymer structure.” Id. at 2:6–9. (...) We review the Board’s legal conclusions de novo and its factual findings for substantial evidence. See ACCO Brands Corp. v. Fellowes, Inc., 813 F.3d 1361, 1365 (Fed. Cir. 2016). Substantial evidence is “such relevant evidence as a reasonable mind might accept as adequate to support a conclusion.” In re Gartside, 203 F.3d 1305, 1312 (Fed. Cir. 2000) (citations omitted). Claim construction is ultimately a question of law that may be based on underlying factual findings. Teva Pharms. U.S.A., Inc. v. Sandoz, Inc., 574 U.S. 318, 332–33 (2015). Thus, we review the Board’s claim constructions de novo and review any underlying factual determinations for substantial evidence. Wasica Fin. GmbH v. Cont’l Auto. Sys., Inc., 853 F.3d 1272, 1278 (Fed. Cir. 2017). (...) Kamstrup argues that the Board erred in construing “cast in one piece” as a product-by-process claim element. A product-by-process claim is one in which a product is claimed, at least in part, by the “process by which it is made.” In re Thorpe, 777 F.2d 695, 697 (Fed. Cir. 1985). Product-by-process claims “enable an applicant to claim an otherwise patentable product that resists definition by other than the process by which it is made.” Id. “In determining validity of a product-by-process claim, the focus is on the product and not the process of making it. That is because of the . . . long-standing rule that an old product is not patentable even if it is made by a new process.” Greenliant Sys., 692 F.3d at 1268 (citations omitted). “As we recognized in Amgen, if the process by which a product is made imparts ‘structural and functional differences’ distinguishing the claimed product from the prior art, then those differences ‘are relevant as evidence of no anticipation’ although they ‘are not explicitly part of the claim.’” Id. (quoting Amgen Inc. v. F. Hoffman-La Roche Ltd, 580 F.3d 1340, 1365–67 (Fed. Cir. 2009)). The specification, the prosecution history, and any extrinsic evidence may enlighten whether structural and functional differences exist. Amgen, 580 F.3d at 1365–67; Purdue Pharma L.P. v. Epic Pharma, LLC, 811 F.3d 1345, 1353–54 (Fed. Cir. 2016). (...) First, even if true, Kamstrup has not identified functional and structural differences between a structure “cast in one piece” and a structure manufactured using another method. Rather, the argument is merely that the claim element describes a manufacturing method with some inherent restrictions. Further, Kamstrup has not identified disclosure in the specification or prosecution history or extrinsic evidence evidencing structural and functional differences. Second, the alleged structural and functional difference that Kamstrup identifies is detached from the claims. The claims state that the structure should be “cast in one piece,” not cast in one mold. ’957 patent at 6:40–42 (emphasis added). The Board correctly found that the written description “focuses on reducing the number of steps required to fabricate the flow meter housing, not on casting in a single mold.” Axioma, 2021 WL 1235790, at *7 (citing ’957 patent at 1:55–57, 2:6–9). While certain figures of the written description, namely Figures 5A and 5B, depict a single mold, the Board correctly found that those embodiments are narrower than the claims—which do not require use of a single mold—and correctly declined to import narrower limitations from the specification to the claims. Id. Substantial evidence also supports the Board’s finding that the extrinsic evidence does not exclusively show that “cast in one piece” means “cast in one mold.” Id. at *8. Consequently, we hold that because Kamstrup fails to show that the process claimed imparts “structural and functional differences” distinguished from the prior art, it is not entitled patentable weight. Greenliant Sys., 692 F.3d at 1268.