Opinion ID: 772062
Heading Depth: 2
Heading Rank: 4

Heading: Prosecution History Estoppel/Doctrine of Equivalents

Text: 31 This case falls squarely within the reach of this court's decision in Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., Ltd., 234 F.3d 558, 56 USPQ2d 1865 (Fed. Cir. 2000) (en banc). When a claim amendment creates prosecution history estoppel with regard to a claim element, there is no range of equivalents available for the amended claim element. Id. at 569, 56 USPQ2d at 1872. That is, [a]pplication of the doctrine of equivalents to [that] claim element is completely barred . . . . Id. This complete bar applies regardless of whether the amendment is explained or unexplained, if the amendment narrows the scope of the claim for a reason related to patentability . . . . Id. at 576, 56 USPQ2d at 1878. 32 In this case, the '391 applicant added the term admixture to the pertinent claims in the amendment after final rejection of the '396 application -- prosecution history that applies to the admixture limitation of claim 1 of the '791 patent -- to distinguish Debregeas. This amendment was related to patentability. Indeed, the '505 patent issued with the admixture limitation shortly after it was added. Further, in the examiner's summary of an interview with the applicant prior to submission of the amendment after final rejection of the '396 application, the examiner stated that a declaration, which was subsequently submitted, showing . . . a homogeneous admixture of [d]iltiazem in combination with the wetting agent . . . would be considered for distinction over [Debregeas]. 33 Because the admixture limitation was added to the pertinent claim language in the relevant prosecution history for reasons related to patentability, Biovail is completely barred from claiming that any product not containing an admixture as properly construed by this court infringes claim 1 of the '791 patent under the doctrine of equivalents. Id. That is, when application of the doctrine of equivalents to a limitation is completely barred due to prosecution history estoppel, a patentee asserting infringement must show by a preponderance of the evidence that an allegedly infringing device literally reads on that limitation as properly construed. 34 We have determined that the admixture limitation in claim 1 of the '791 patent must be homogeneous. Biovail does not contend that diltiazem salt and sugar in Andrx's product are homogeneously admixed in the dry state. As discussed previously, the district court's factual findings that Biovail failed to prove by a preponderance of evidence that Andrx's product forms a homogeneous admixture in the body are not clearly erroneous. Therefore, Andrx's product does not meet the admixture limitation of claim 1 of the '791 patent either in the dry state or in vivo. Consequently, based on the complete bar raised by prosecution history estoppel, Andrx's product does not infringe claim 1 of the '791 patent under the doctrine of equivalents.