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Festo's Absolute Bar for Limitations in Amended Claims Applies to the Same Limitations in Unamended Claims

December 17, 2001

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Last Month at the Federal Circuit - January 2002

Judges: Lourie (author), Newman, and Rader

In Intermatic Inc. v. Lamson & Sessions Co., No. 00-1101 (Fed. Cir. Dec. 17, 2001), the Federal Circuit affirmed-in-part and reversed-inpart several decisions of the district court concerning infringement.

Intermatic Inc. ("Intermatic") owns U.S. Patent No. 5,280,135 ("the '135 patent") directed to weatherproof electrical-outlet covers. These patented covers accommodate a variety of electrical-outlet orientations by combining a base plate with an aperture, a removable insert, and a protective housing. The claims of the '135 patent include two key limitations: the first requires the insert to be adapted to fit within the aperture of the base plate (the "insert within the aperture" limitation); and the second requires the insert to accommodate electrical outlets positioned in a first orientation and a second orientation (the "multiple orientation" limitation).

The Lamson & Sessions Company ("Lamson") manufactures weatherproof electricaloutlet covers, including a base plate with an aperture, one or two removable inserts, and a protective housing. Lamson's inserts, however, do not fit within the aperture of the base plate. Some of these inserts include ribs that extend into the aperture (the "ribbed products"), while others do not (the "ribless products"). And, although Lamson's inserts can accommodate either horizontally oriented or vertically oriented outlets, a single insert cannot accommodate both orientations.

Intermatic sued Lamson for infringement of the '135 patent by the ribbed products ("Intermatic I"). Although the district court had granted Lamson's motion for SJ that the ribbed products did not literally infringe, it denied Lamson's motion as to infringement under the DOE. A jury subsequently found that the ribbed products infringed a group of fifteen claims under the DOE. The jury also found three dependent claims invalid for obviousness, but not the corresponding independent claims. The district court had granted Intermatic's motion for JMOL that these three dependent claims were not invalid, given the inconsistency in the jury's verdict.

During Intermatic I, Lamson initiated a reexamination of the '135 patent that resulted in a narrowing amendment adding the "insert within the aperture" limitation to one independent claim of that group for a reason related to patentability.

After the reexamination, Intermatic sued Lamson again, alleging infringement of the '135 patent by the ribless products ("Intermatic II"). Here, the district court granted Lamson's motion for SJ of noninfringement, holding that the ribless products did not literally infringe and that prosecution history estoppel barred a finding of infringement under the DOE.

On appeal, the Federal Circuit first agreed with the district court's claim construction of the two key limitations and the finding of no literal infringement. In addressing infringement under the DOE, the Court noted that under Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 234 F.3d 558 (Fed. Cir. 2000) (en banc), the narrowing amendment during reexamination absolutely barred any range of equivalents for that limitation in the amended claim. Additionally, the Court extended that absolute bar to all of the claims in which the "insert within the aperture" limitation appeared, even if they had not been amended.

Finding no infringement by the ribbed products, the Federal Circuit affirmed-in-part (literal infringement) and reversed-in-part (infringement under the DOE) Intermatic I. Similarly, finding no infringement by the ribless products, the Court affirmed Intermatic II.

Dissenting-in-part, Judge Newman argued that Festo does not go so far as to require a narrowed limitation in an amended claim to absolutely bar any range of equivalents for the same limitation in an unamended claim.