The Reverse Doctrine of Equivalents is Rarely Applied

Roche Palo Alto LLC v. Apotex, Inc., [2008-1021] (July 9, 2008) [PROST, Michel, Hochberg] The Federal Circuit affirmed summary judgment that U.S> Patent No. 5,110,493 directed to a drug formulation for treatment of eye inflammation, is valid and infringed by the formulation covered by Apotex’s abbreviated new drug application (“ANDA”).
BRIEF: Plaintiff moved for summary judgment that defedant’s modified formula infringed, based upon the prior case between the parties in which the patent was found valid and infringed. Defendant countered by arguing that the modified formulation escapes infringement under the reverse doctrine of equivalents. LOF: non-infringement under the reverse doctrine of equivalents is a question of fact.
The reverse doctrine of equivalents is an equitable doctrine designed “to prevent unwarranted extension of the claims beyond a fair scope of the patentee’s invention.” While the patentee bears the burden of proving infringement, if the patentee establishes literal infringement, the burden shifts to the accused infringer to set forth a prima facie case of non-infringement under the reverse doctrine of equivalents. The Federal Circuit noted that the reverse doctrine of equivalents is rarely applied, and this court has never affirmed a finding of non-infringement under the reverse doctrine of equivalents. The Federal Circuit agreed with the district court that defendants failed to set forth a prima facie case of non-infringement under the reverse doctrine of equivalents because it did not properly establish the principle of the patent. The Federal Circuit said that the “principle” or “equitable scope of the claims” of the patented invention is determined in light of the specification, prosecution history, and the prior art.
On the issued of claim preclusion, the Federal Circuit said claim preclusion applies where: “(1) the same parties, or their privies, were involved in the prior litigation, (2) the prior litigation involved the same claim or cause of action as the later suit, and (3) the prior litigation was terminated by a final judgment on the merits.” The parties were the same, and the prior litigation resulted in a final judgment, so the issued was whether the litigation involved the same causes of action. The Federal Circuit said that the second suit is the “same claim” as in an earlier infringement suit if the accused products in the two suits are “essentially the same.” The Federal Circuit explained that accused products “are ‘essentially the same’ where the differences between them are merely ‘colorable’ or ‘unrelated to the limitations in the claim of the patent.’ The Federal Circuit agreed with the district court that as far as the claims in suit, the two products were not substantially different.