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Court Adheres to ITC’s Claim Construction and the Plain Meaning of Claim Terms

August 27, 2010

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Last Month at The Federal Circuit - September 2010

Judges: Newman (concurring), Dyk, Prost (author)

[Appealed from: ITC]

In Pass & Seymour, Inc. v. International Trade Commission, Nos. 09-1338, -1369 (Fed. Cir. Aug. 27, 2010), the Federal Circuit affirmed the ITC’s claim construction and determination that certain accused products do not infringe U.S. Patent Nos. 5,594,398 (“the ’398 patent”) and 7,212,386 (“the ’386 patent”), and therefore do not violate section 337 of the Tariff Act of 1930, as amended.

Pass and Seymour, Inc. (“P&S”) is the assignee of the ’398 and ’386 patents, which relate to improved safety features of circuit interrupters for use with household electrical appliances.  The asserted claims were initially construed by an ALJ, and the accused products, produced by General Protecht Group, Inc. (“GPG”), Wenzhou Trimone Science and Technology Electric Co., Ltd. (“Trimone”), and Shanghai ELE Manufacturing Corporation (“ELE”), were found to infringe the ’398 and ’386 patents.  On review, the ITC modified the ALJ’s claim constructions of certain disputed terms and reversed the finding of infringement.  On appeal, the Federal Circuit reviewed the ITC’s claim construction de novo and its factual findings for substantial evidence.

The ’398 patent describes improved ground fault circuit interrupters, which operate by detecting a difference in electrical current flowing into and out of the connected appliance, then opening the circuit to disrupt the flow of electrical current.  The Court first addressed the construction of an asserted claim term describing the “mounting means” for a conducting member, which permits movement between a first position, where the pair of contacts are in respective, circuit-making engagement with terminals, and a second position, “wherein both of said pair of contacts are in spaced, circuit-breaking relation to said pair of terminals.”  See slip op. at 8.  The ALJ construed the claim term to mean that if either of the two contacts moved into a spaced, circuit-breaking second position, “both” would be in a position that resulted in circuit breaking.  Rejecting the ALJ’s interpretation, the Court agreed with the ITC’s modified construction that the plain language of the claim requires that “both” contacts move into a spaced, circuit-breaking position in relation to the terminals.  The Court stated that “if P&S wanted its claim to read on devices where only one contact moved into spaced, circuit breaking relation to the terminals, then it could have written its claim to read, ‘wherein at least one of said pair of contacts is in spaced, circuit-breaking relation to said pair of terminals.’”  Id. at 9-10.  The Court agreed with the ITC’s determination that the accused products did not contain contacts that “both” move into a spaced second position, and therefore did not meet the literal claim requirements or perform the stated function of the “mounting means” limitation.

The Court next considered the disputed claim term “a unitary, electrically conducting member carrying a pair of spaced electrical contacts,” and agreed with the ITC’s construction that the plain meaning of the term “unitary” requires that both electrical contacts be disposed on the same single unit.  The Court found that the specification and prosecution history confirm that the plain meaning is appropriate in the context of this claim limitation.  Id. at 10 (citing Phillips v. AWH Corp., 415 F.3d 1303, 1316 (Fed. Cir. 2005)).  The Court noted that the specification teaches that “unitary” refers to “the nature of the member’s physical structure, not just its electrical relationship with two contacts.”  Id.  In the accused devices, the electrical contacts are supported on separate plates of metal, connected only by a braided wire.  According to the Court, “It is not enough that the wire is permanently welded to each of the two plates . . . as though it were a single conducting unit.”  Id. at 11.  Rather, the claim language requires the conducting member carrying the pair of contacts “actually” be a single conducting unit.

Because the accused products did not meet the “mounting means” limitation, and thus did not meet every limitation of the asserted claims, the Court concluded that there could be no infringement.  Id. (citing Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S. 15, 29 (1997)).  The Court added that the finding that some accused products also do not meet the “unitary conducting member” limitation provided an additional reason as to why the accused products do not infringe.

The ’386 patent relates to a device that protects users and appliances from damage caused by miswiring, by generating different types of signals in response to different operating conditions.  The Court addressed the disputed claim term describing a circuit interrupter coupled to the actuator assembly, “the circuit interrupter being configured to disconnect the first conductive path from the second conductive path in response to the actuator signal in the reset state.”  Slip op. at 12.  The Court agreed with the ITC’s construing of the claim to mean that the circuit interrupter had to be configured to trip in response to the actuator signal, or ultimately in response to the wiring state detection signal, in the reset state.  According to this interpretation, the Court held that it follows that the patented device must be configured to trip in response to a signal that the device is properly wired, which the ITC acknowledged “was not perfectly logical, and may have been the result of a claim drafting error.”  Id.  The Court added that the wiring state detection circuit and the actuator assembly claim elements do not contain limitations as to the circuit state.  As a result, these components of the device must generate their respective signals at least once, without regard to the state of the device (i.e. reset or tripped).

P&S’s objection relied on a statement in the specification that “the wiring state detection circuit operates when the line terminal is powered and the appliance is properly wired, and not when it is improperly wired.”  Id. at 14.  P&S argued that it makes no sense to require a miswiring protection device to be configured to trip a properly wired appliance and not an improperly wired appliance.  The Court explained, however, that the plain language of the claims did not allow for an exception to the consequence described above.  Therefore, even though a device may include additional wiring state detection circuits that generate signals only in the tripped state, it must still contain at least one wiring state protection circuit that generates a signal at least once when power is applied, without respect to the state of the device.  Because the accused products did not contain such a circuit, id. at 15 (citing Warner-Jenkinson, 520 U.S. at 29), the Court affirmed the ITC’s finding of noninfringement, and determination that importation and sale of the accused products into the United States does not violate section 337 of the Tariff Act.

In a concurring opinion, Judge Newman wrote that the Court erred in the construction and application of the clause in the ’386 patent, “circuit interrupter” in interaction with the “actuator assembly.”  Judge Newman stated that claim construction requires conformity with the description of the invention in the specification.  Newman Concurrence at 2 (citing Phillips, 415 F.3d at 1315).  Judge Newman added that, in this case, “[t]he court’s understanding of the claims as requiring tripping of the circuit whenever the device is wired properly, is contrary to the purposes, function, and operation of the claimed device.  It is not the claim that is not ‘logical,’ it is the claim construction that defies the specification.”  Id. at 3 (footnote and citation omitted).  Judge Newman agreed with the ITC’s construction and conclusion that a device configured to disconnect in response to an actuator signal received in response to a wiring state detection signal in the reset state need not actually generate a wiring state detection signal in the reset state, and therefore need not actually trip when properly wired (although it must be configured to do so).  Judge Newman concluded that she would adhere to the ITC’s construction and accordingly find that the accused products do not infringe the claims at issue in the ’386 patent.

Summary authored by Nicole H. Kattah, Ph.D., student associate at Finnegan.