`
`IN THE UNITED STATES DISTRICT COURT
`FOR THE EASTERN DISTRICT OF TEXAS
`TYLER DIVISION
`
`CASE NO. 6:08CV30
`
`§§§§§
`
`§§§§§
`
`NETWORK-1 SECURITY SOLUTIONS,
`INC.
`
`Plaintiff,
`
`vs.
`
`CISCO SYSTEMS, INC., ET AL
`
`Defendants.
`
`MEMORANDUM OPINION AND ORDER
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`This Memorandum Opinion construes the disputed terms in U.S. Patent No. 6,218,930 (the
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`“’930 Patent”). The Court further GRANTS in part and DENIES in part Defendants’ Motion for
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`Partial Summary Judgment of Invalidity for Indefiniteness (Docket No. 206).
`
`BACKGROUND
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`The ’930 Patent issued on April 17, 2001 to Boris Katzenberg and Joseph Deptula. The ’930
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`Patent discloses a set of circuits that enable the delivery of operating power over Ethernet
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`(commonly referred to as “PoE”) only to those access devices that are designed to accept such power.
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`PoE technology is not new. PoE delivers both data and operating power to network access devices
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`over an Ethernet network, allowing devices such as voice over IP telephones, security cameras, etc.
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`to be mounted in areas without regard for whether there is an adequate separate power supply for the
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`devices.
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`The problem with traditional PoE systems is that damage can occur when power is delivered
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`to an access device that is not designed to accept it. The ’930 Patent provides “methods and
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`N 212919
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`Case 6:08-cv-00030-LED Document 251 Filed 02/16/2010 Page 2 of 27
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`apparatus for reliably determining if a remote piece of equipment is capable of accepting remote
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`power.” ’930 Patent, col.1:41–44. “It is another object of this invention to provide methods and
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`apparatus for delivering remote power to remote equipment over 10/100 switched Ethernet segments
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`and maintain compliance with the IEEE 802.3 standards.” Id. at 1:45–48.
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`This case is the second lawsuit that involves the ’930 Patent. Prior to this case, Network-1
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`Security Solutions, Inc. (“Network-1”) brought suit in August 2005 and alleged infringement of the
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`’930 Patent. The Court construed the disputed terms of the ’930 Patent in November 2006.
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`Network-1 Sec. Solutions, Inc. v. D-Link Corp. & D-Link Sys., Inc., Case No. 6:05cv291,
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`Memorandum Opinion and Order (Docket No. 137) (E.D. Tex. Nov. 20, 2006) (the “D-Link case”).
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`In the present case, Network-1 alleges that Cisco Systems, Inc., Cisco-Linksys, L.L.C., Adtran, Inc.,
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`Enterasys Networks, Inc., Extreme Networks, Inc., Foundry Networks, Inc., Netgear, Inc., and 3Com
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`Corporation (collectively, “Defendants”) infringe Claims 1, 2, 6, and 9 of the ’930 Patent.1
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`APPLICABLE LAW
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`“It is a ‘bedrock principle’ of patent law that ‘the claims of a patent define the invention to
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`which the patentee is entitled the right to exclude.’” Phillips v. AWH Corp., 415 F.3d 1303, 1312
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`(Fed. Cir. 2005) (en banc) (quoting Innova/Pure Water Inc. v. Safari Water Filtration Sys., Inc., 381
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`F.3d 1111, 1115 (Fed. Cir. 2004)). In claim construction, courts examine the patent’s intrinsic
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`evidence to define the patented invention’s scope. See id.; C.R. Bard, Inc. v. U.S. Surgical Corp.,
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`388 F.3d 858, 861 (Fed. Cir. 2004); Bell Atl. Network Servs., Inc. v. Covad Commc’ns Group, Inc.,
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`262 F.3d 1258, 1267 (Fed. Cir. 2001). This intrinsic evidence includes the claims themselves, the
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`specification, and the prosecution history. See Phillips, 415 F.3d at 1314; C.R. Bard, Inc., 388 F.3d
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`1
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` Claims 1, 2, 6, and 9 of the ’930 Patent are reproduced in Appendix A.
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`2
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`N 212920
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`at 861. Courts give claim terms their ordinary and accustomed meaning as understood by one of
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`ordinary skill in the art at the time of the invention in the context of the entire patent. Phillips, 415
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`F.3d at 1312–13; Alloc, Inc. v. Int’l Trade Comm’n, 342 F.3d 1361, 1368 (Fed. Cir. 2003).
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`The claims themselves provide substantial guidance in determining the meaning of particular
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`claim terms. Phillips, 415 F.3d at 1314. First, a term’s context in the asserted claim can be very
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`instructive. Id. Other asserted or unasserted claims can also aid in determining the claim’s meaning
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`because claim terms are typically used consistently throughout the patent. Id. Differences among
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`the claim terms can also assist in understanding a term’s meaning. Id. For example, when a
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`dependent claim adds a limitation to an independent claim, it is presumed that the independent claim
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`does not include the limitation. Id. at 1314–15.
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`“[C]laims ‘must be read in view of the specification, of which they are a part.’” Id. (quoting
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`Markman v. Westview Instruments, Inc., 52 F.3d 967, 979 (Fed. Cir. 1995) (en banc)). “[T]he
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`specification ‘is always highly relevant to the claim construction analysis. Usually, it is dispositive;
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`it is the single best guide to the meaning of a disputed term.’” Id. (quoting Vitronics Corp. v.
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`Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996)); Teleflex, Inc. v. Ficosa N. Am. Corp., 299
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`F.3d 1313, 1325 (Fed. Cir. 2002). This is true because a patentee may define his own terms, give
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`a claim term a different meaning than the term would otherwise possess, or disclaim or disavow the
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`claim scope. Phillips, 415 F.3d at 1316. In these situations, the inventor’s lexicography governs.
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`Id. Also, the specification may resolve ambiguous claim terms “where the ordinary and accustomed
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`meaning of the words used in the claims lack sufficient clarity to permit the scope of the claim to be
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`ascertained from the words alone.” Teleflex, Inc., 299 F.3d at 1325. But, “‘[a]lthough the
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`specification may aid the court in interpreting the meaning of disputed claim language, particular
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`3
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`embodiments and examples appearing in the specification will not generally be read into the
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`claims.’” Comark Commc’ns, Inc. v. Harris Corp., 156 F.3d 1182, 1187 (Fed. Cir. 1998) (quoting
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`Constant v. Advanced Micro-Devices, Inc., 848 F.2d 1560, 1571 (Fed. Cir. 1988)); see also Phillips,
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`415 F.3d at 1323. The prosecution history is another tool to supply the proper context for claim
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`construction because a patent applicant may also define a term in prosecuting the patent. Home
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`Diagnostics, Inc., v. Lifescan, Inc., 381 F.3d 1352, 1356 (Fed. Cir. 2004) (“As in the case of the
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`specification, a patent applicant may define a term in prosecuting a patent.”).
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`Although extrinsic evidence can be useful, it is “‘less significant than the intrinsic record in
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`determining the legally operative meaning of claim language.’” Phillips, 415 F.3d at 1317 (quoting
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`C.R. Bard, Inc., 388 F.3d at 862). Technical dictionaries and treatises may help a court understand
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`the underlying technology and the manner in which one skilled in the art might use claim terms, but
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`technical dictionaries and treatises may provide definitions that are too broad or may not be
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`indicative of how the term is used in the patent. Id. at 1318. Similarly, expert testimony may aid
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`a court in understanding the underlying technology and determining the particular meaning of a term
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`in the pertinent field, but an expert’s conclusory, unsupported assertions as to a term’s definition is
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`entirely unhelpful to a court. Id. Generally, extrinsic evidence is “less reliable than the patent and
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`its prosecution history in determining how to read claim terms.” Id.
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`The patent in suit also contains a means-plus-function limitation that require construction.
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`Where a claim limitation is expressed in “means plus function” language and does not recite definite
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`structure in support of its function, the limitation is subject to 35 U.S.C. § 112, ¶ 6. Braun Med., Inc.
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`v. Abbott Labs., 124 F.3d 1419, 1424 (Fed. Cir. 1997). In relevant part, 35 U.S.C. § 112, ¶ 6
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`mandates that “such a claim limitation ‘be construed to cover the corresponding structure . . .
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`4
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`N 212922
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`Case 6:08-cv-00030-LED Document 251 Filed 02/16/2010 Page 5 of 27
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`described in the specification and equivalents thereof.’” Id. (citing 35 U.S.C. § 112, ¶ 6).
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`Accordingly, when faced with means-plus-function limitations, courts “must turn to the written
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`description of the patent to find the structure that corresponds to the means recited in the
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`[limitations].” Id.
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`Construing a means-plus-function limitation involves multiple inquiries. “The first step in
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`construing [a means-plus-function] limitation is a determination of the function of the means-plus-
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`function limitation.” Medtronic, Inc. v. Advanced Cardiovascular Sys., Inc., 248 F.3d 1303, 1311
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`(Fed. Cir. 2001). Once a court has determined the limitation’s function, “the next step is to
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`determine the corresponding structure disclosed in the specification and equivalents thereof.” Id.
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`A “structure disclosed in the specification is ‘corresponding’ structure only if the specification or
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`prosecution history clearly links or associates that structure to the function recited in the claim.” Id.
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`Moreover, the focus of the “corresponding structure” inquiry is not merely whether a structure is
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`capable of performing the recited function, but rather whether the corresponding structure is “clearly
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`linked or associated with the [recited] function.” Id.
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`CLAIM TERMS
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`Data node
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`Claims 1, 2, and 6 of the ’930 Patent contain the term “data node.” Network-1 contends that
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`the term means “Ethernet switch or hub,” while Defendants contend that it means “data switch or
`2
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`hub.” The parties disagree whether or not the term “data node” is limited to an Ethernet
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`environment.
`
`2
` This construction of “data node” was adopted by the Court in the D-Link case. However, in that case, the
`construction was agreed on by the parties, and the Court did not resolve whether or not the term was limited to an
`Ethernet environment.
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`5
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`N 212923
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`Network-1 asserts that the specification repeatedly describes an Ethernet limitation, which
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`makes it a requirement of the claim scope. Defendants counter that the claims do not recite an
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`Ethernet limitation, and that although the preferred embodiment is in the context of an Ethernet
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`system, the specification does not characterize the invention as a whole to include an Ethernet
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`limitation. Defendants also argue that restricting the term to the preferred Ethernet embodiment
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`improperly imports a limitation from the specification.
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`The ’930 Patent does not describe the Ethernet as a feature of the present invention as a
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`whole, which is required to limit the scope of the claimed invention. See Honeywell Int’l., Inc. v.
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`ITT Indus., 452 F.3d 1312, 1318–19 (Fed. Cir. 2006); Scimed Life Sys., Inc. v. Advanced
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`Cardiovascular Sys., Inc., 242 F.3d 1337, 1343 (Fed. Cir. 2001). The specification more broadly
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`refers to a variety of telecommunications and data communications equipment and a desire to
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`remotely power data network devices from a centrally powered system during power outages. ’930
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`Patent, col. 1:22–40. Additionally, the specification sets forth a general objective of determining if
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`remote equipment is capable of accepting remote power followed by a specific objective of
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`delivering power over switched Ethernet segments in accordance with IEEE 802.3 standards. See
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`id. at 1:41–48. The Summary of the Invention implies that Ethernet power is in accordance with
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`only the specific objective, not the general objective. See id. at 1:51–59. The scope of the invention
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`as a whole is not limited to Ethernet power, and other network topologies do not preclude use of the
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`claimed invention. Accordingly, Ethernet is not a proper limitation, and the Court adopts
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`Defendants’ construction and construes the term “data node” to mean “data switch or hub.”
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`6
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`N 212924
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`Access device
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`Claims 1, 2, 6, and 9 of the ’930 Patent contain the term “access device.” Network-1
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`contends that the term means “a device that can access an Ethernet network,” while Defendants
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`contend that it means “a piece of equipment that requires power to access a network and to receive
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`and transmit data.” The parties disagree whether or not the term “access device” is limited to an
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`Ethernet network and whether or not it can receive and transmit data.
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`Network-1 asserts that the ordinary and customary meaning of the term is merely a device
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`that can access. Further, Network-1 asserts that, in the context of the claim limitation as a whole,
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`the term means a device adapted to access a data network, particularly an Ethernet network.
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`Defendants counter that the Court’s construction in the D-Link case, which Network-1 then agreed
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`to, remains proper because it is consistent with the specification and inclusion of an Ethernet
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`requirement is improper.
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`Inherent in the term “‘access device’ adapted for data transmission” is the fact that the device
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`requires electrical power to operate. See ’930 Patent, col. 4:13. Network-1’s construction, other than
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`the improper inclusion of “Ethernet” as addressed in the discussion of the term “data node,” adds
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`nothing beyond the understandable meaning of the term itself. Defendants’ construction, which
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`Network-1 agreed to in the D-Link case, adds the superfluous recitation of “a piece of equipment that
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`requires power.” This language repeats what the claim element itself states, so the Court will
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`adopt a simpler, clearer definition than it did in the D-Link case. Accordingly, the Court construes
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`the term “access device” to mean “a device that can receive and transmit data over a network.”
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`7
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`N 212925
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`Main power source
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`Claims 1 and 6 of the ’930 Patent contain the term “main power source.” Network-1
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`contends that the term needs no construction or, in the alternative, means “source of main power,”
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`while Defendants contend that it means “a DC power source that provides the specified power for
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`the data node and the low level current delivered to the access device.” The parties disagree whether
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`or not the term “main power source” is limited to DC power.
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`Network-1 asserts that Defendants’ construction is vague as to “specified power” and limits
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`“main power source” to be a DC power source without support in the specification for making that
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`limitation. If the term is construed, Network-1 also asserts that its construction should be adopted
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`because “main” and “secondary” refer to supplying power for two different operating modes.
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`Defendants counter that, in the context of the claim as a whole, the term is restricted to a DC power
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`source. Further, Defendants argue that Network-1’s assertion that “main” and “secondary” refer to
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`a single power-providing device with two operating modes is inconsistent with both the claims and
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`the specification.
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`The claim language specifies that the main power source is “connected to supply power to
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`the data node.” ’930 Patent, col. 4:17–18. Figure 3 below shows that the main power source is a
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`source of DC power.
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`8
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`N 212926
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`Figure 3 of the ’930 Patent
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`In Figure 3, main power supply 70 is energized from an AC electrical outlet connection to deliver
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`“main” power to the 8-Port Ethernet switches 68, which have secondary power sources. The words
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`“source” and “supply” are used interchangeably in the ’930 Patent as seen in Claim 4, which refers
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`to the “source” from Claim 1 as “said . . . supply.” See ’930 Patent, col. 4:19, 4:44–45. Figure 1
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`showing Power Source 16 is not a separate embodiment of the invention, as the specification states
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`that “Fig[ure] 3 illustrates the physical layout of components corresponding to” Figure 1, where
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`Figure 1 is merely a “simplified schematic diagram.” ’930 Patent, col. 3:59–60, 2:21–25.
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`Network-1 attempts to construe the term broadly to include an AC electrical outlet as a “main
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`power source,” but a construction of such a breadth is inconsistent with the specification. See Wang
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`Labs., Inc. v. Am. Online, Inc., 197 F.3d 1377, 1383 (Fed. Cir. 1999) (stating that “[t]he usage
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`‘preferred’ does not of itself broaden the claims beyond their support in the specification” and
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`9
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`N 212927
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`Case 6:08-cv-00030-LED Document 251 Filed 02/16/2010 Page 10 of 27
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`finding that “the claims were correctly interpreted as limited” to “[t]he only embodiment described
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`in the . . . specification”). Further, the construction of “main power source”cannot be broader than
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`what the inventors actually invented, as determined from the scope of the disclosure in the
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`specification. See Netword, LLC v. Centraal Corp., 242 F.3d 1347, 1352 (Fed. Cir. 2001) (stating
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`that “[a]lthough the specification need not present every embodiment or permutation of the invention
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`and the claims are not limited to the preferred embodiment of the invention, . . . neither do the claims
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`enlarge what is patented beyond what the inventor has described as the invention”).
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`The remainder of Defendants’ construction, “that provides the specified power for the data
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`node and that the low level current delivered to the access device,” is superfluous, as the information
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`is contained in the claim itself, which specifies that power is supplied by the main power source to
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`the data node and the low level current is delivered from the main power source. See, e.g., ’930
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`Patent, col. 4:17–18, 4:22–23. Accordingly, the Court construes the term “main power source” to
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`mean “a DC power source.”
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`Secondary power source
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`Claims 1, 2, 6, and 9 of the ’930 Patent contain the term “secondary power source.”
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`Network-1 contends that the term means “source of secondary power; the secondary power source
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`need not be physically separate from the main power source,” while Defendants contend that it
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`means “a source of power connected to provide power between the data node and the access device
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`using the data signaling pair. The secondary power source is physically separate from the main
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`power source.” The parties disagree whether or not the term “secondary power source” requires the
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`secondary power source to be physically separate from the main power source.
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`10
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`N 212928
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`Case 6:08-cv-00030-LED Document 251 Filed 02/16/2010 Page 11 of 27
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`Network-1 asserts that since the D-Link case, Federal Circuit cases have demonstrated that
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`the “secondary power source” need not be physically separate from the “main power source.” See,
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`e.g., Linear Tech. Corp. v. ITC, 566 F.3d 1049, 1055 (Fed. Cir. 2009) (holding that the terms
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`“second circuit” and “third circuit” do “not require entirely separate and distinct circuits” with each
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`“requir[ing] a specific structural requirement”); Oatey Co. v. IPS Corp., 514 F.3d 1271, 1275 (Fed.
`
`Cir. 2008) (holding that the term “first and second juxtaposed drain ports” does not require “two
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`separate identifiable physical elements”). Network-1 also asserts that the claim language does not
`
`specify that the sources are physically separate, and inclusion of this limitation in the construction
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`excludes a preferred embodiment from the scope of the claim. Finally, Network-1 asserts that the
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`claim refers to a secondary mode of operation, not to a separate connection.
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`Defendants counter that the claims recite two distinct power sources that must be physically
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`separate, where the main power source supplies power to the data node and the secondary power
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`source supplies power from the data node. Defendants also argue that the Federal Circuit cases cited
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`by Network-1 do not support its position because they involve embodiments where components are
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`shared. Finally, Defendants argue that there is no support for Network-1’s contention that two
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`modes of operation of a single power source are being described in the ’930 Patent.
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`The Federal Circuit cases cited by Network-1 are inapposite. Unlike in Linear, the terms at
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`issue in this case are not “second” and “third” as mere identifiers; rather, the terms “main” and
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`“secondary” set forth an operational hierarchy. Furthermore, the Court’s construction in the D-Link
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`case does not impose a requirement of “entirely separate and distinct.” Linear, 566 F.3d at 1055
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`(emphasis added). Unlike in Oatey, the Court’s construction in the D-Link case does not require
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`“separate identifiable physical elements” for each of the power sources. Oatey, 514 F.3d at 1275
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`11
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`N 212929
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`(emphasis added). The Court’s construction in the D-Link case requires only that there be physically
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`separate “driving points” because each power source “drives” a separate load. Network-1 Sec.
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`Solutions, Inc. v. D-Link Corp. & D-Link Sys., Inc., Case No. 6:05cv291, Memorandum Opinion and
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`Order (Docket No. 137) (E.D. Tex. Nov. 20, 2006). The hierarchy of “main” and “secondary” also
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`indicates a physical separateness, particularly because two different loads (the data node and the
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`access device) are being driven. This is true even though the electrical energy applied to the access
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`device via the data node originates from the main power source.
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`Network-1 is incorrect that an embodiment is excluded with the requirement of physical
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`separateness. The argument is based on Power Source 16 in Figure 1, which Network-1 asserts
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`shows that the main and secondary power sources are the same. Although Power Source 16 is
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`depicted as a single power source in Figure 1, it must provide the electrical energy that goes to both
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`the data node and the access device. See ’930 Patent, fig. 1. Thus, the functional block diagram of
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`Figure 1 does not identify where the main and secondary power sources are located, nor how they
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`are physically arranged.
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`The functional block diagram of Figure 1 is shown in detail in Figure 3 where main power
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`supply 70 supplies power to Ethernet switches 68. ’930 Patent, col. 3:66–4:1. Ethernet switches 68
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`include the power detector 22 of Figure 1 and the power supply 34 of Figure 2. Id. at 4:1–4. In
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`Figure 2, the feed and return lines of the remote power supply are identified as lines 39 and 45,
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`respectively. Id. at 3:37–38. The RJ45 connector 43 of Figure 2 is specified for a network cable
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`connection using the CAT-5 Ethernet Premises Wiring of Figure 3. See id. at figs. 2–3. The feed
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`line corresponds to line 18 in Figure 1, and the return line corresponds to return path 20 in Figure
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`1. Id. at 2:52–59. Thus, Figure 1, when read in conjunction with Figures 2 and 3 by one of ordinary
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`12
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`N 212930
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`Case 6:08-cv-00030-LED Document 251 Filed 02/16/2010 Page 13 of 27
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`skill in the art, does not show an embodiment without separate power sources. Instead, the figures
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`show a clear hierarchy of the main power source, then the secondary power source to the data node,
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`and finally the access device from the data node.
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`Figure 2 below identifies terminals 6 and 3 as an active pair and, similarly, terminals 1 and
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`2 as an active pair. ’930 Patent, col. 3:31–37. Ethernet networks utilize at least two signaling pairs.
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`See id. at 1:56–58. Delivering supply power from the data node via the data signaling pairs to the
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`access device, which is the operative arrangement of the secondary power source, finds support in
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`the specification discussing Figure 2. See id. at 3:28–42. The disclosure of transformers between
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`the feed and return lines and the data signaling pairs also implies physical separateness. See id. The
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`arrangement of transformers electrically isolates the electrical load of the access device from the
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`electrical load of the data node. Thus, electrically separate power sources are established for the data
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`node (from the main power source) and the access device (from the secondary power source).
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`Figure 2 of the ’930 Patent
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`13
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`N 212931
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`Case 6:08-cv-00030-LED Document 251 Filed 02/16/2010 Page 14 of 27
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`Thus, the main power source in the disclosed embodiment is main power supply 70 of Figure
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`3, and the secondary power source is power supply 34 of Figure 2. See ’930 Patent, figs. 2–3. The
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`primary power to drive the data node established by the Ethernet switches 68 is provided by the
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`connection of the Main Power Distribution Bus in Figure 3. See id. at fig. 3. The secondary power
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`to drive the access device is provided by the RJ45 connector in Figure 2 at the end of the CAT-5
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`Ethernet Premises Wiring in Figure 3. See id. at figs. 2–3.
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`Finally, the claim language specifies that a low level current is supplied from the main power
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`source to the access device over the data signaling pair. ’930 Patent, col. 4:22–25. This indicates
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`that, in view of the other claim elements as to the secondary power source, the secondary power
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`source is physically separate from the main power source. See id. at 4:10–29. The element that
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`supplies power to the access device is the secondary power source. Id. at 4:19–21. In light of the
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`specification, the claim language indicates that the secondary power source is used between the main
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`power source and the access device as a type of controlled valve for electrical energy applied from
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`the main power source to the access device. Claim 4 is more specific than Claim 1 in placing the
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`secondary power source in the data node. See id. at 4:43–45. Claim 4 further confirms the
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`indication in Figure 3 that power supply 34 of Figure 2 is the secondary power source. See id. at fig.
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`2. Accordingly, the Court adopts its previous construction in the D-Link case and Defendants’
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`construction and construes the term “secondary power source” to mean “a source of power connected
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`to provide power between the data node and the access device using the data signaling pair. The
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`secondary power source is physically separate from the main power source.”
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`14
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`N 212932
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`Case 6:08-cv-00030-LED Document 251 Filed 02/16/2010 Page 15 of 27
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`Low level current
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`Claims 1 and 6 of the ’930 Patent contain the term “low level current.” Network-1 contends
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`that the term means “a current at a level that is sufficiently low that it will not (a) operate the access
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`device, or (b) damage an access device that is not designed to accept power though the data signaling
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`pair,” while Defendants contend that it means “a current sufficient to cause the access device to start
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`up, but not sufficient to sustain the start up.” The parties disagree what level of current the term
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`“low level current” requires.
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`Network-1 asserts that Defendants’ construction defeats the objective of the ’930 Patent to
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`use a low level current that will not cause damage to an access device that cannot accept remote
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`power. Network-1 also asserts that Defendants’ construction is improperly derived from the
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`described operative effect of the preferred embodiment in response to a low level current.
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`Defendants counter that the objective is to determine whether an access device can accept remote
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`power, and Network-1’s construction is inconsistent with that objective. Defendants also argue that
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`the specification does not describe the use of a low level current in terms of not operating or
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`damaging the access device.
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`The claim language ties low level current to producing a varying voltage level, which is the
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`“preselected condition” of the claim, if the access device can accept remote power. ’930 Patent, col.
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`4:22–29. Network-1’s construction is overly broad and inconsistent with the specification because
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`it does not characterize the low level current in terms of producing the preselected condition of the
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`resulting voltage level. Although the specification implies that the low level current will not damage
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`the access device if it cannot accept remote power, this generalized characterization is not
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`sufficiently explicit to encompass the production of a resulting voltage level of a preselected
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`condition. See ’930 Patent, col. 1:17–19, 1:54–56.
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`Defendants’ construction does not limit the term to the preferred embodiment. The term is
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`a relative term of degree, so some objective guidance must be provided by the specification, as
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`Network-1 agrees. See Exxon Research & Eng’g Co. v. United States, 265 F.3d 1371, 1381 (Fed.
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`Cir 2001). Apart from the preferred embodiment, where the presence of a dc-dc power supply
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`produces a sawtooth waveform, the only objective standard in the specification states that
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`determination of whether an access device can accept remote power is based on a response in the
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`return path to a low level current applied to a circuit. ’930 Patent, col. 2:66–3:2. Thus, the only
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`objective benchmark to guide one skilled in the art is a varying voltage level produced in the return
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`path when the access device is beginning to start up, but is unable to sustain start up. This standard
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`is necessary to guide one skilled in the art in determining a “low level current” in the context of the
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`’930 Patent and provides a signpost as to whether an accused device is delivering a low level current
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`from the main power supply. Accordingly, the Court adopts its construction from the D-Link case
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`and Defendants’ construction and construes the term “low level current” to mean “a current
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`sufficient to cause the access device to start up, but not sufficient to sustain the start up.”
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`Preselected condition
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`Claims 1 and 6 of the ’930 Patent contain the term “preselected condition.” Network-1
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`contends that the term means “any parameters of the voltage on the signaling pair that indicates
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`whether an access device is able to accept remote power from the data node,” while Defendants
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`contend that it means “a parameter of the voltage on the signaling pair that indicates whether an
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`access device is able to accept remote power from the data node, where a fixed level voltage drop
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`or no voltage drop indicates that the access device is unable to accept power from the data node.”
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`The parties disagree whether the term “preselected condition” requires detectable conditions of the
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`resulting voltage level produced.
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`Network-1 asserts that Defendants improperly seek to import limitations from the
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`specification. Defendants counter that the specification makes a disclaimer of the conditions of a
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`fixed voltage drop and no voltage drop.
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`Defendants’ construction does not encompass a disclaimer, but it does improperly impose
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`additional detectable conditions of a resulting voltage level produced in response to a low level
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`current. A “preselected condition” determines whether or not an access device can accept remote
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`power and does not contemplate conditions that might indicate that the access device cannot accept
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`remote power. See ’930 Patent, col. 2:66–3:27. Defendants are making a misplaced attempt to
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`include what a preselected condition is not rather than merely stating what it is, so the additional
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`limitation of “where a fixed level voltage drop or no voltage drop indicates that the access device
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`is unable to accept power from the data node” is improper. Network-1’s construction adds “any
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`parameters,” however the claim specifies “a resulting voltage level” on the signaling pair. ’930
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`Patent, col. 4:24–25. Thus, the specification does not contemplate multiple or any parameters of a
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`voltage on the signaling pair. Accordingly, the Court construes the term “preselected condition” to
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`mean “a parameter of the voltage on the signaling pair that indicates whether an access device is able
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`to accept remote power from the data node.”
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`Phantom power
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`Claim 2 of the ’930 Patent contains the term “phantom power.” Network-1 contends that the
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`term means “operating power transmitted over the data signaling pairs that does not affect the
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`simultaneous transfer of data,” while Defendants contend that it means “operating power transmitted
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`over the data signaling pairs.” The parties disagree whether or not the term “phantom power” relates
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`to the effect of power on data.
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`Network-1 asserts that the term signifies the transparency of the power to the data.
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`Defendants counter that the term only signifies that power and data are both transmitted