Important to determination of the infringement issue, also, are the findings establishing the pioneer nature of the Eis inventions (Eis abandoned the traditional design of thickening equipment; results obtained were “surprising”, “striking”, “unexpected” and “synergistic”; Eis’ process is “far more effective” than conventional equipment; “Nothing ... indicated the kind of results one could obtain if the Eis process was used”; the entire industry testing procedure was modified or abandoned “wholly dependent upon the teachings of the Eis patent”).
The statute provides no support for the district court’s statement that “the combinative nature of Amstar’s patent rights effectively limits the scope of enforceable claims under the Eis patent”. There is no separate classification of “combination patents” and no basis for considering claims to combinations of elements differently from any other. Richdel, Inc. v. Sunspool Corp., 714 F.2d 1573, 1579, 219 USPQ 8, 12 (Fed.Cir.1983); Medtronic, Inc. v. Cardiac Pacemakers, 721 F.2d 1563, 220 USPQ 97, 100 (Fed.Cir.1983).
As discussed infra, a statement made during prosecution of the application for the ’889 patent which related to avoidance of mixing in the settling zone, cannot be applied as a form of estoppel precluding application of the claims to Envirotech’s apparatus which also avoided mixing in the settling zone.
The district court’s Memorandum Decision overlooked the claim charts (Px 32) introduced and analyzed at trial and presented here as part of Amstar’s brief on appeal. Those charts establish unequivocally that the accused apparatus employed at Envirotech’s pilot plants, and as originally sold to Eagle Coal and Dock and to EFN, constituted literal infringements of claims 1, 8, and 9.
The record further illustrates that the modifications assertedly made by Envirotech, whenever they may have been made, are either irrelevant or fail to escape infringement. The accused products, including those modified, are the same, they perform the same function in the same way, and they achieve, as the district court found, the same result as the claimed inventions. See Sanitary Refrigerator Co. v. Winters, 280 U.S. 30, 41-42, 50 S.Ct. 9, 12-13, 74 L.Ed. 147, 3 USPQ 40, 44 (1929).
In this case, the merely colorable variations so vigorously pressed by Envirotech are of a kind with those described by the Supreme Court as fostering “the piracy” and consequent defeat of the disclosure purpose of the patent system. Graver Tank, supra, 339 U.S. at 607, 70 S.Ct. at 855, 85 USPQ at 330. Infringement. is clear on this record.6
Envirotech’s Brief7
The brief filed by Envirotech on this appeal, presented to assist this court in determining that the finding of non-infringement was not clearly erroneous, contains not one reference to any step of process claims 1 and 8, or to any element of product claim 9, that is even asserted to be absent from the accused processes and products of Envirotech.
Unable to point to any part of Eis’ claimed inventions not appropriated by it, Envirotech says it avoided infringement solely because it added mechanical pre-mix
6
The district court’s treatment of differences in the Amstar and Envirotech commercial products included a statement (repeated in Envirotech’s brief here) that Amstar’s approach to equivalence could lead to a conclusion that, except for a simple design difference, "a Phillips head screwdriver is a standard screwdriver”. The district court’s error of law, repetition of which is sought here by Envirotech, lies in the failure, as above indicated, to compare the accused products and processes with the claimed products and processes.
7
Envirotech challenges none of the findings on which rests the district court’s conclusion that the '889 patent is valid. Nor does Envirotech challenge the district court’s finding that it produced the accused products because its thickener business was "in jeopardy” as a result of Amstar’s presence in what Envirotech’s engineers called its “sandbox”.