Opinion ID: 754812
Heading Depth: 3
Heading Rank: 2

Heading: Doctrine of Equivalents Infringement

Text: 44 Chiuminatta argues that, should we rule against it on the question of literal infringement, we may affirm the district court under the doctrine of equivalents. Although the district court did not reach the issue because it found literal infringement, Chiuminatta argues that the undisputed evidence of record conclusively establishes that the wheels of the accused device differ from the patented invention only insubstantially. Such an assertion cannot succeed given our determination regarding literal infringement under § 112, p 6. 45 Although an equivalence analysis under § 112, p 6, and the doctrine of equivalents are not coextensive (for example, § 112, p 6, requires identical, not equivalent function) and have different origins and purposes, their tests for equivalence are closely related. Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S. 17, ----, 117 S.Ct. 1040, 1048, 137 L.Ed.2d 146, 41 USPQ2d 1865, 1870-71 (1997) ([Equivalents under § 112] is an application of the doctrine of equivalents in a restrictive role, narrowing the application of broad literal claim elements. We recognized this type of role for the doctrine of equivalents in Graver Tank itself.). Both § 112, p 6, and the doctrine of equivalents protect the substance of a patentee's right to exclude by preventing mere colorable differences or slight improvements from escaping infringement, the former, by incorporating equivalents of disclosed structures into the literal scope of a functional claim limitation, and the latter, by holding as infringements equivalents that are beyond the literal scope of the claim. They do so by applying similar analyses of insubstantiality of the differences. Thus, a finding of a lack of literal infringement for lack of equivalent structure under a means-plus-function limitation may preclude a finding of equivalence under the doctrine of equivalents. 46 There is an important difference, however, between the doctrine of equivalents and § 112, p 6. The doctrine of equivalents is necessary because one cannot predict the future. Due to technological advances, a variant of an invention may be developed after the patent is granted, and that variant may constitute so insubstantial a change from what is claimed in the patent that it should be held to be an infringement. Such a variant, based on after-developed technology, could not have been disclosed in the patent. Even if such an element is found not to be a § 112, p 6, equivalent because it is not equivalent to the structure disclosed in the patent, this analysis should not foreclose it from being an equivalent under the doctrine of equivalents. 47 That is not the case here, where the equivalence issue does not involve later-developed technologies, but rather involves technology that predates the invention itself. In such a case, a finding of non-equivalence for § 112, p 6, purposes should preclude a contrary finding under the doctrine of equivalents. This is because, as we have already determined, the structure of the accused device differs substantially from the disclosed structure, and given the prior knowledge of the technology asserted to be equivalent, it could readily have been disclosed in the patent. There is no policy-based reason why a patentee should get two bites at the apple. If he or she could have included in the patent what is now alleged to be equivalent, and did not, leading to a conclusion that an accused device lacks an equivalent to the disclosed structure, why should the issue of equivalence have to be litigated a second time? As indicated, this consideration does not necessarily apply regarding variants of the invention based on after-developed technologies. 48 Our case law clearly provides that equivalence under the doctrine of equivalents requires that each claim limitation be met by an equivalent element in the accused device. Because this requirement is not met for § 112, p 6, purposes with respect to one limitation, it is therefore not met in this case for doctrine of equivalents purposes. An element of a device cannot be not equivalent and equivalent to the same structure. See, e.g., Dawn Equip. Co. v. Kentucky Farms Inc., 140 F.3d 1009, 1017-22, 46 USPQ2d 1109, 1115-18 (Fed.Cir.1998) (Plager, J., additional views). 49 In this case there can also be no doctrine of equivalents infringement because, as we have explained, the structure in the accused device, the wheels, operates in a substantially different way compared with the structure of the claimed device, the skid plate. The former support the surface of the concrete by rolling over the concrete while the latter skids. The former are soft, compressible, and round; the latter is hard and predominantly flat (albeit with rounded edges to prevent gouging of the concrete). Additionally, the wheels rotate as opposed to skid as the saw moves across the concrete and thus have a different impact on the concrete. The wheels flatten slightly, applying more localized pressure against the concrete than that produced by a hard flat skid plate. Accordingly, for this additional reason, it cannot be an equivalent under the doctrine of equivalents and the district court is directed to enter summary judgment of non-infringement. See Cool Fuel, Inc. v. Connett, 685 F.2d 309, 311 (9th Cir.1982) (noting that a court may sua sponte grant summary judgment to the non-moving party where the moving party cannot prove its case on the undisputed facts).