Opinion ID: 297956
Heading Depth: 1
Heading Rank: 3

Heading: the infringement question

Text: 22 Ordinarily, at least, the question of infringement is a question of fact to be resolved by the trier of the facts in the light of all of the evidence. 23 Thus, in McCullough Tool Company v. Well Surveys, Inc., 343 F.2d 381 (10th Cir. 1965), this Court said: 24 The question of infringement is one of fact and, upon review, the trial court's findings thereon will not be set aside unless they are clearly erroneous. Stilz v. United States, 269 U.S. 144. 46 S.Ct. 37, 70 L.Ed. 202; Hahn & Clay v. A. O. Smith Corporation, 5 Cir., 320 F.2d 166, cert. denied, 375 U.S. 944, 84 S.Ct. 351, 11 L.Ed.2d 274. Therefore, our power of review is limited to determining whether, under correct legal standards, the findings of infringement are supported by the record. In McCullough it was noted that 25 In determining whether an accused device infringes a valid patent, resort must be had in the first instance to the words of the claims contained in the patent   . 26 However, the Court also stated that this is not conclusive since infringement is not a mere matter of words. Rather, the test is whether the accused device and the device covered by the patent do the same work in substantially the same way to accomplish substantially the same result. The Court went on to say: 27 Under the doctrine of equivalents, infringement may exist even though the two devices differ in name, form or shape. Graver Tank Co. v. Linde Air Products Co., supra. Equivalency must be determined against the context of the patent, the prior art and the particular circumstances of the case and complete identity for every purpose and in every respect is not required. Jones v. Bodaness [10 Cir., 189 F.2d 838], supra. 28 A primary or pioneer patent, such as Bender, is to be given a broad and liberal construction and, also, a broad and liberal range of equivalence and it is not to be limited to the precise device and instrumentality disclosed. Mason Corporation v. Halliburton, 10 Cir., 118 F.2d 729; Priebe & Sons Co. v. Hunt, 8 Cir., 188 F.2d 880, cert. dismissed, 342 U.S. 801, 72 S.Ct. 92, 96 L.Ed. 607. A combination patent which constitutes a marked improvement in the art, such as Fearon, is entitled to a substantial range of equivalents. 29 The trial court's finding No. 11 that the file wrapper of the Thurley patent made clear that there was no question of fact as to Claim 1 being limited to a plurality of high intensity combustion burners was a crucial one which laid the groundwork for the court's further finding that the plaintiff's plurality of burners ruled out infringement. This called for a most careful interpretation of the proceedings before the examiner by one skilled in the art. On the basis of the sparse record before it, and judging from the complexity of the proceedings before the examiner, the trial court was necessarily handicapped in arriving at such a finding. We find it impossible to review this determination. The findings do not cite the applicable pages of the file wrapper and support for the finding is not found in the total proceedings of the examiner. Explanatory testimony was therefore necessary, and it was error to determine the issue without this assistance. 30 While the two structures have some differences they also have similarities whereby the court should hear evidence as to whether they perform substantially the same function in substantially the same way to achieve substantially the same result. Plaintiff is entitled to an opportunity to prove at a trial that the accused device is the functional equivalent of the Thurley patent.