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“Practicing the Prior Art” Is Not a Defense to Literal Infringement

February 07, 2002

Decision icon Decision

Last Month at the Federal Circuit - March 2002

Judges: Gajarsa (author), Plager, and Dyk

In Tate Access Floors, Inc. v. Interface Architectural Resources, Inc., No. 01-1275 (Fed. Cir. Feb. 7, 2002), the Federal Circuit affirmed a district court’s grant of a preliminary injunction.

Tate Access Floors, Inc. and Tate Access Floors Leasing, Inc. (collectively “Tate”) own U.S. Patent No. 4,625,491 (“the ’491 patent”) directed to raised access flooring panels. These removable panels, resting side by side on pedestals, form an elevated floor under which cables and pipes can be run and through which they can be accessed. The claims of the ’491 patent recite a panel including a decorative, exterior surface on one side of the panel, an interior portion underneath and contrasting with the exterior surface, and a border around the edges of the panel along which the exterior surface is removed to expose the interior portion. Drawings in the ’491 patent depict an embodiment of a panel in which the visible surface includes three regions—central, peripheral, and beveled. In the central region, a flat, full-thickness exterior surface covers the interior portion. In the peripheral region, the exterior surface is completely removed to expose a flat interior portion. In the beveled region between the two, the exterior surface transitions from full thickness at a boundary with the central region to completely removed at a boundary with the peripheral region.

Interface Architectural Resources, Inc. (“Interface”) also made raised-access flooring panels. The Interface panels included only two regions similar to the Tate panels—central and beveled—and, thus, did not include a peripheral region with a completely removed exterior surface.

Tate sued Interface in the U.S. District Court for the District of Maryland, alleging infringement of the ’491 patent. Upon Tate’s motion for preliminary injunction, the district court examined four factors: likelihood of success on the merits (including both validity and infringement), irreparable harm, balance of hardships, and public policy. In a first key decision, the district court interpreted the term “border” to read on the beveled region of Interface’s non-peripheralregion panels. In a second key decision, the district court rejected Interface’s “practicing the prior art” defense. Finding for Tate on each of the four factors, the district court granted the preliminary injunction.

The Federal Circuit examined the only issue on appeal, Tate’s likelihood of success on the merits regarding infringement. The Court first dismissed Interface’s “practicing the prior art” defense to literal infringement, rejecting Interface’s arguments based on DOE, reverse DOE, and Scott Paper Co. v. Marcalus Manufacturing Co., 326 U.S. 249 (1945). The Federal Circuit stated that Baxter Healthcare Corp. v. Spectramed, Inc., 49 F.3d 1575 (Fed. Cir. 1995) directly foreclosed the “practicing the prior art” defense. Additionally, the Court noted that DOE cases are inapposite to literal infringement, that the Federal Circuit has never affirmed a decision finding noninfringement based on reverse DOE, and that Scott Paper is likely premised on invalidity, not noninfringement, as a defense to an infringement action. The Court then found the term “border,” as used in the ’491 patent, clear and unambiguous, and the district court’s interpretation of that term fully supported by the specification. Therefore, finding no abuse of discretion by the  district court, the Federal Circuit affirmed the grant of the preliminary injunction.