U.S. International Trade Commission Investigation No. 337-TA-615; Certain Ground Fault Circuit Interrupters

HQ H054476 February 22, 2010 ENF-4-02-OT:RR:BSTC:IPR H054476 WRB CATEGORY: 19 U.S.C. § 1337; Unfair Competition Ann G. Fort, Esq. Malvern U. Griffin, III, Esq. Sutherland, Asbill & Brennan LLP 999 Peachtree Street, NE Atlanta, Georgia 30309-3996 RE: U.S. International Trade Commission Investigation No. 337-TA-615; Certain Ground Fault Circuit Interrupters Dear Ms. Fort and Mr. Griffin: This is in reply to your May 20, 2009, letter, in which you request on behalf of your client, General Protecht Group, Inc. (“GPG”), an administrative ruling, pursuant to 19 CFR Part 177, as to whether certain ground fault circuit interrupters (“GFCIs”) are excluded from entry into the United States pursuant to the limited exclusion order issued by the U.S. International Trade Commission (ITC) in Investigation No. 337-TA-615. You provided samples of your client’s 2008 GFCI device. A typical GFCI device is illustrated below:


 FACTS: On March 9, 2009, the U.S. International Trade Commission (ITC) issued a limited exclusion order (LEO: 337-TA-615) excluding certain ground fault circuit interrupter (GFCI) devices and products containing the same that infringe the referenced claims of the relevant patents, (Claims 1 and 7 of U.S. Patent No. 5,594,398 (“the ‘398 patent”), and claims 14 and 18 of U.S. Patent No. 7,283,340 (“the ‘340 patent”)), and that are manufactured abroad by or on behalf of, or imported by or on behalf of GPG of Zheijiang, China; or any of their affiliated companies, parents, subsidiaries, or other related business entities, or any of their successors or assigns from entry for consumption into the United States, entry for consumption from a foreign trade zone, or withdrawal from a warehouse for consumption. DESCRIPTION OF TECHNOLOGY AND PATENTS AT ISSUE: The above-referenced investigation at the ITC involved GFCIs and products containing the same used in electronic devices. In the standard technology at the time of the invention, GFCI devices “trip” (or break) a circuit when the devices detect excess current, thereby preventing shock. If the user miswires the GFCI, the power can flow through a circuit without the GFCI tripping mechanism and thereby provide no shock protection. Through various electrical and mechanical solutions, the patents attempt to ensure that the GFCI will provide shock protection, even when miswired. The devices covered by ‘398 patent address the miswiring issue with mechanical springs which push the GFCI’s electrical contacts into the trip position when miswired. The devices covered by ‘340 patent addresses the miswiring issue with a protective device that detects the GFCI’s wiring state and conducts current only if the GFCI is wired properly. ISSUE: The issue presented is whether the above-referenced GFCI manufactured by GPG falls within the scope of the ITC’s limited exclusion order in Investigation No. 337-TA-615 such that these GFCIs and products containing the same should be excluded from entry as directed by the limited exclusion order. LAW AND ANALYSIS: Section 337 of the Tariff Act of 1930, as amended (19 U.S.C. § 1337), prohibits, inter alia, the importation, the sale for importation, or the sale within the United States after importation by the owner, importer, or consignee of articles that infringe a valid and enforceable U.S. patent. 19 U.S.C. § 1337(a)(1)(B)(i). The ITC has authority to investigate alleged violations of section 337. 19 U.S.C. § 1337(b). If the ITC determines that there has been a violation of section 337, it shall, subject to certain potential exceptions, direct that the articles concerned be excluded from entry into the United States and, accordingly, notify the Secretary of the Treasury who shall, through its proper officers,  refuse such entry. 19 U.S.C. § 1337. See also, 19 CFR § 12.39. In ITC Investigation No. 337-TA-615, the ITC determined that certain GFCIs manufactured by GPG infringed claims 1 and 7 of U.S. Patent No. 5,594,398 (“the ‘398 patent”), and claims 14 and 18 of the U.S. Patent No. 7,283,340 (“the ‘340 patent”), owned by Pass & Seymour, Inc., (“P&S”). Therefore, the ITC ordered that GFCI devices infringing claims 1 and 7 of the ‘398 patent, and claims 14 and 18 of the ‘340 patent, manufactured abroad by or on behalf of, or imported by or on behalf of GPG, inter alia, or any of their affiliated companies, parents, subsidiaries, or other related business entities, or any of their successors or assigns, shall be excluded from entry for consumption into the United States, entry for consumption from a foreign trade zone, or withdrawal from a warehouse for consumption for the remaining terms of the patents, and notified CBP accordingly. Limited Exclusion Order, Certain Ground Fault Circuit Interrupters and Certain Products Containing Same, Investigation No. 337-TA-615 (March 9, 2009). To warrant a finding of patent infringement, an accused article must meet each limitation of any of the claims of a patent either literally or under the doctrine of equivalents. Charles Greiner & Co. v. Mari Med Mfg., Inc., 962 F.2d 1031, 1034 (Fed. Cir. 1992). In order to find literal infringement, every limitation of the claim must be found exactly in the subject article. Amhil Enters, Ltd. v. Wawa, Inc., 81 F.3d 1554, 1562 (Fed. Cir. 1996); Southwall Techs, Inc. v. Cardinal IG Co., 54 F.3d 1570, 1575 (Fed. Cir. 1995). The U.S. Supreme Court has described the essential inquiry of the doctrine of equivalents analysis in terms of whether the accused product or process contains elements identical or equivalent to each claimed element of the patented invention. Warner-Jenkinson Co., Inc. v. Hilton Davis Chemical Co., 520 U.S. 17, 40 (1997). If an element is missing or not satisfied, infringement cannot be found under the doctrine of equivalents as a matter of law. See, e.g., Wright Medical, 122 F.3d 1440, 1444 (Fed. Cir. 1997); Dolly, Inc. v. Spalding & Evenflo Cos., Inc., 16 F.3d 394, 398 (Fed. Cir. 1994); London v. Carson Pirie Scott & Co., 946 F.2d 1534, 1538-39 (Fed. Cir. 1991); Becton Dickinson and Co. v. C.R. Bard, Inc., 922 F.2d 792, 798 (Fed. Cir. 1990). I. Infringement analysis regarding claims 1 and 7 of the ‘398 patent: The ‘398 patent, entitled “Ground Fault Interrupter Wiring Device with Improved Moveable Contact System,” discusses the object of the invention as the ability, “…to provide a gfi wiring device having novel and improved means for carrying the moveable contacts and for transmitting current between fixed contacts during normal operation." (col. 1, lines 34-37). The asserted claims in the ‘398 patent are: 1. A ground fault interrupter (gfi) wiring device for connection in an electrical circuit, said device comprising: a) housing means defining an enclosed space; b) at least one pair of electrical terminals fixedly supported in spaced relation within said enclosed space; c) a unitary, electrically conducting member carrying a pair of spaced electrical contacts; d) mounting means for said conducting member to permit movement thereof between a first position, wherein said pair of contacts are in respective, circuit-making engagement with said pair of terminals, and a second position, wherein both of said pair of contacts are in spaced, circuit-breaking relation to said pair of terminals; e) biasing means urging said conducting member toward movement to said second position; f) latching means releasably retaining said conducting member in said first position; and g) actuating means for releasing said latching means to permit said biasing means to move said conducting member to said second position in response to a predetermined fault condition in said electrical circuit. 6. The gfi device of claim 1 wherein said device is a gfi receptacle and said housing means includes a plurality of apertures for receiving the blades of an electrical plug. 7. The gfi device of claim 6 wherein said device is a two-pole device including first and second pairs of spaced electrical terminals, first and second electrically conducting members each carrying a pair of spaced electrical contacts, and mounting means for both of said conducting members to permit concurrent movement thereof between circuit-making and circuit-breaking relation of said contacts said terminals. (Emphasis Supplied) The International Trade Commission construed the terms in bold above. The language, “A unitary, electrically conducting member carrying a pair of spaced electrical contacts;” was construed as “A single member carrying two or more spaced contacts that provides an electrical current-carrying path between two or more spaced contacts.” (Commission Opinion, p. 6). The ITC determined that this construction did not read onto to the “unitary member” of GPG’s 2003 GFCI because it did not have a single member carrying two contacts. Rather, the contacts were on physically separate metal plates connected by only a braided wire. (Comm'n Op., p.7) Accordingly, the GPG 2003 GFCI was held not to infringe this claim. Similarly, the GPG 2008 GFCl device does not include “a unitary, electrically conducting member carrying a pair of spaced electrical contacts.” Like the 2003 GFCl device, the 2008 GFCl device does not include “a single member carrying two or more spaced contacts that provides an electrical current-carrying path between two or more spaced contacts.” The 2008 GFCl device has contacts carried on separate metal plates. The metal plates are connected to a power source by braided wire.
The language, “Mounting means for said conducting member to permit movement thereof between a first position, wherein said pair of contacts are in respective, circuit-making engagement with said pair of terminals, and a second position, wherein both of said pair of contacts are in spaced, circuit-breaking relation to said pair of terminals;” was construed by the ITC in terms of both function and structure: • Function 1: Mounts said conducting member. (Comm'n Op., p. 8-9). • Function 2: "Permits movement between a first position, wherein a pair of contacts are in respective, circuit-making engagement with a pair of terminals, and a second position, wherein both of the pair of contacts are in spaced, circuit-breaking relation to the pair of terminals." (Id.). • "Both of the contacts must be permitted to move into spaced, circuitbreaking relation to the pair of terminal." (Id.). • Structure: "A block including a central body and an arm for supporting the conducting member, and structural equivalents thereof." (Id.): The GPG 2008 GFCI device does not include "mounting means for said conducting member to permit movement thereof between a first position, wherein said pair of contacts are in respective, circuitmaking engagement with said pair of terminals, and a second position, wherein both of said pair of contacts are in spaced, circuit-breaking relation to said pair of terminals." The 2008 GFCI device permits only one contact to move into a spaced, circuit breaking relation. The other contact remains fixed and electrically connected to the terminal, and does not move into a spaced, circuit-breaking position in relation to the terminal.

Upon review, we are of the opinion that GPG's 2008 GFCl device does not infringe claims 1 or 7 in the '398 patent. Regarding claim 1, the 2008 GFCl device does not include a “unitary, electrically conducting member carrying a pair of spaced electrical contacts.” The 2008 GFCl device does not include a “mounting means for said conducting member to permit movement thereof between a first position, wherein said pair of contacts are in respective, circuit-making engagement with said pair of terminals, and a second position, wherein both of said pair of contacts are in spaced, circuit- breaking relation to said pair of terminals.” Claim 7 depends from claim 6, which depends in turn from claim 1. Accordingly, claim 7 cannot be infringed unless claim 1 is also infringed. Therefore, the Commission's limited exclusion order does not exclude GPG's 2008 GFCl device from entry because the 2008 GFCl device does not infringe claims 1 or 7 in the '398 patent for the same reasons as the 2003 GFCI device. II. Infringement analysis regarding Claims 14 and 18 of the '340 Patent: The '340 patent characterizes the invention as providing a protective device that detects the wiring state of the device and inhibits device operation if the device is miswired. (col. 2, lines 28-31). The asserted claims in the '340 patent are: 14. An electrical wiring device comprising: (a) line terminals and load terminals; (b) at least one detection circuit including a circuit segment coupled between the line terminals and configured to generate a predetermined signal in response to detecting a proper wiring condition, the predetermined signal not simulating a fault condition, a proper wiring condition being effected when the line terminals are connected to a source of AC power; and (c) an interrupting contact assembly coupled to the at least one detection circuit, the interrupting contact assembly including four sets of interrupting contacts that are configured to provide electrical continuity between the line terminals and the load terminals in a reset state and configured to interrupt the electrical continuity in tripped state, the interrupting contact assembly being substantially prevented from effecting the reset state absent the predetermined signal being generated by the at least one detection circuit. 18. The device of claim 14, wherein the at least one detection circuit includes a wiring state detection circuit configured to generate the predetermined signal. (Emphasis Supplied) The ALJ construed the claim 14 language "At least one detection circuit including a circuit segment coupled between the line terminals" of the '340 patent, to mean "at least one detection circuit having a circuit segment connected between the line terminals, either directly or indirectly, and configured to generate a predetermined signal in response to detecting a wiring condition, which occurs when the line terminals are connected to a source of AC power." (ALJ Initial Determination, p. 85-87). Similarly, the ALJ construed the claim 14 language, “A predetermined signal in response to detecting a proper wiring condition, the predetermined signal not simulating a fault condition,” as meaning that a predetermined signal is "a signal set in advance of installation that does not simulate a fault condition." (ALJ ID, p. 88) “When electrical power is correctly connected to the line terminals, will trip only once (if it is in the reset state). If the device is already in the tripped state, nothing visible happens. Once the device is reset, it will not trip again unless it is responding to a test input or a true fault condition." (‘340 patent, col. 4, lines 26-30). The ITC adopted the ALJ’s claim construction of the term “detection circuit” to mean “at least one detection circuit having a circuit segment connected between the line terminals and configured to generate a predetermined signal in response to detecting a proper wiring condition, which occurs when the line terminals are connected to a source of AC power.” In re Certain Ground Fault Circuit Interrupters and Products Containing Same, Inv., No., 337-TA-615, Initial Determination at p. 85 (September 24, 2008.) During the prosecution of the ‘340 patent, Pass & Seymour amended the claims to avoid prior art, with claim 14 issuing in its final form, with the differences indicated below: 14. An electrical wiring device comprising: line terminals and load terminals; at least one detection circuit including a circuit segment coupled between the line terminals and/or the load terminals, the at least one detection circuit being and configured to generate a predetermined signal in response to detecting a proper wiring condition, the predetermined signal not simulating a fault condition, a proper wiring condition being effected when the line terminals are connected to a source of AC power; and an interrupting contact assembly coupled to the at least one detection circuit, the interrupting contact assembly including four sets of interrupting contacts that are configured to provide electrical continuity between the line terminals and the load terminals in a closed reset state and configured to interrupt the electrical continuity in tripped state, the interrupting contact assembly being substantially prevented from effecting the reset state absent the predetermined signal being generated by the at least one detection circuit. (See Prosecution History of the ‘340 Patent, Claim Amendments of July 3, 2007, at p.10 and August 15, 2007, at p.8.) Neither the Commission nor the ALJ addressed the distinctions between these “coupled to” and “coupled between” The “coupled between” language should be more narrowly construed than “coupled to" based upon the '340 patent's prosecution history; and the '340 patent's disclosure. As originally drafted in the patent application, claim 14 covered a device with at least one detection circuit coupled to the line terminals and/or the load terminals. Claim 14 was narrowed during prosecution to cover a device with at least one detection circuit coupled between the line terminals. This amendment was made to overcome the patent examiner's rejection based on a prior art circuit covered by U.S. Patent No. 6,111,733 (“the ’733 patent”). In the circuit covered by the ‘733 patent, current passes only one way through the circuit, from the hot terminal to the neutral terminal, but not bi-directionally. This narrowing amendment was made to overcome a prior art circuit that included unidirectional current flow. Therefore, “coupled between” should be construed as a more narrow term than “coupled to” as coupled “between” requires bi-directional current flow, and unidirectional current flow in “coupled to” was disclaimed. Claim 14 was amended to claim a device with "at least one detection circuit including a circuit segment coupled between the line terminals….” Accordingly, by employing the patent’s prosecution history, the determination here is that claim 14 of the ‘340 patent does not cover a GFCI with unidirectional current flow. In the exemplary embodiment of the '340 patent, current passes bi-directionally through the miswire detection circuit to and from the hot and neutral terminals. “Coupled to” is also a broader term than "coupled between;" “coupled to” meaning without regard to the direction of current flow. Per the specification, the language “coupled to” has a special meaning, in that the circuit is not connected to both the hot and neutral conductors. “In this manner the protective functions described in FIG. 1 are provided without necessarily requiring a differential current transformer L1 in the construction of the protective device nor attachment of the fault resistor and fuse circuit to both the hot and neutral line conductors.” (‘340 patent, Detailed Description, para. 18; Col. 7, lines 28-33). The ALJ found that the 2003 GFCl device had a circuit coupled between the line terminals. The GPG 2003 Reset Control Circuit was found to be indirectly connected between both the hot and neutral conductors through the full wave rectifier circuit, allowing bi-directional current flow through the reset control circuit to and from the hot and neutral conductors through the full wave rectifier circuit. (ALJ's ID, Sept. 24, 2008).
The analysis above is consistent with the ALJ 's decision and is consistent with the construction of the "between" language as requiring bi-directional current flow. Accordingly, based on the prosecution history and specification of the '340 patent, the term “between” in the phrase “circuit segment coupled between the line terminals” in claim 14 means the circuit segment is connected to both line conductors such that current flow in the circuit segment is bi-directional. The 2003 GFCl device was found to be indirectly connected between the line terminals because the 2003 Reset Control Circuit was connected to the full wave rectifier circuit, allowing bi-directional current flow. Therefore, the rectifier circuit was coupled between the line terminals. However, the 2008 GFCl device has been redesigned, with the 2008 Reset Control Circuit no longer being connected to a full wave rectifier circuit; and current flow no longer being bidirectional. The GPG 2008 GFCI device has a Reset Control Circuit, but the Reset Control Circuit is not a circuit coupled between the line terminals, because the current flow in the 2008 Reset Control Circuit is not bi-directional. Conversely, the Reset Control Circuit in the GPG 2008 device does not exhibit two distinct responses according to whether the line terminals or the load terminals are connected to a source of AC power. Unlike in the GPG 2003 GFCl device, the 2008 GFCl device does not include “at least one detection circuit including a circuit segment coupled between the line terminals.” The 2008 GFCl device has been redesigned to accommodate features that are not present in the 2003 GFCl device. As part of this redesign, the Reset Control Circuit in the 2008 GFCl device is not a circuit coupled between the line terminals as required by claim 14.
In addition, while the Reset Control circuit protects against miswiring, the Reset Control Circuit does not fulfill the definition of an “at least one detection circuit.” A "detection circuit" exhibits two distinct responses according to what it “detects,” such as whether the line terminals or the load terminals are connected to a source of AC power. Without detecting whether the line terminals or the load terminals are connected to a source of AC power, the Reset Control Circuit does not satisfy the functional limitation of an “at least one detection circuit,” as discussed in claim 14. Lacking at least two necessary elements (coupling “between” terminals and the “detection circuit”) recited in claim 14, the GPG 2008 GFCl device cannot literally infringe claim 14 of the '340 patent. Claim 18 depends from claim 14. If an underlying independent claim is not infringed, then all associated dependent claims cannot be infringed as a matter of law. HOLDING: In conformity with the foregoing, the above-referenced ground fault circuit interrupter sample submitted by or on behalf of General Protecht Group, Inc., is not subject to Exclusion Order 337-TA-615. Therefore, the above-referenced GFCIs may be entered for consumption into the United States. Sincerely, Charles R. Steuart, Chief Intellectual Property Rights & Restricted Merchandise Branch