1. Whether, as part of claim construction, an independent claim describing "protecting back panel" as "relatively rigid" or "stiff"can be literally infringed if claim differentiation creates a presumption that each claim has a different scope, but the written description and prosecution history teaches against the presumption.
2. Whether the holding in Chiuminatta Concrete Concepts, Inc. v. Cardinal Indus., Inc., 145 F.3d 1303, 46 USPQ2d 1752 (Fed. Cir. 1998), which precludes a finding of infringement under the doctrine of equivalents for pre-existing technology, applies to patents that do not use means-plus-function claim limitations.
1. No. The doctrine of claim differentiation is only a presumption and is not intended to broaden claims beyond their scope. The written description and prosecution history can overcome the initial presumption from the doctrine of claim differentiation.
2. No. Chiuminatta does not apply to patents that do not use the means-plus-function claim limitation format.
Kraft Foods, Inc. ("Kraft"), owner of US Patent No. 5,657,873 ("the '873 patent"), sued International Trading Co. and Houston Processing LTD. (collectively "ITC") for infringement. The patent describes various structures to be applied to the bottom of compartmentalized rigid base trays in lieu of an outer enclosure, and finds application in the packaging of Kraft's "Oscar Mayer Lunchables" products. Independent Claim 2 recites a food package comprising, inter alia, "a protecting back panel adhered immovably" to the bottom of the trays. ITC makes similar compartment trays and uses labels that adhere to the bottom.
The district court granted ITC's motion for summary judgment of no literal infringement and no infringement under the doctrine of equivalents of claim 2, the only asserted claim of the '873 patent.
The Federal Circuit affirmed summary judgment with regard to the literal infringement finding, but reversed and remanded with respect to the doctrine of equivalents holding. In addressing the first issue, the Court found that the doctrine of claim differentiation creates a presumption that each claim is different in scope and therefore gives rise to a mere presumption that the claim does not exclude back paneling that is not "relatively stiff." The Federal Circuit found, however, that the written description and patent prosecution can overcome the presumption and that the term "protecting back panel" necessarily excludes non-rigid backing. The Court clarified that the presumption of claim differentiation cannot be used to broaden the scope of a claim. Thus, the Court found that ITC's pressure-sensitive, non-rigid labels do not literally infringe claim 2 because they do not meet the claim limitations.
The Court disagreed with the district court's reading of Chiuminatta. That case precluded finding infringement under the doctrine of equivalents where the accused variation of the patented invention involves preexisting technology. The Federal Circuit agreed with Kraft that Chiuminatta applies only to patents with means-plus-function claim limitations. That format was not used here. The Court stated that a finding of infringement under the doctrine of equivalents is not foreclosed by the mere fact that the asserted equivalent structure was preexisting technology, and that claim limitation was not drafted as means-plus-function. Therefore, the Court held that the district court erred in granting summary judgment and remanded for a trial on the issue of infringement under the doctrine of equivalents.
Prepared by the liibulletin-patent Editorial Board.