`
`IN THE UNITED STATES DISTRICT COURT
`FOR THE EASTERN DISTRICT OF TEXAS
`TYLER DIVISION
`
`Civil Action No. 6:10-CV-473
`(LED/KFG)
`
`§§§§§§§§§
`
`ERICSSON INC., et. al.,
`
` v.
`
`Plaintiffs,
`
`D-LINK CORPORATION, et. al.,
`
`
`Defendants.
`
`MEMORANDUM OPINION AND ORDER CONSTRUING CLAIM TERMS OF
`UNITED STATES PATENT NOS.
`6,772,215, 6,330,435, 5,987,019, 6,466,568, and 5,790,516
`
`This claim construction opinion construes the disputed claim terms in U.S. Patent Nos.
`
`6,772,215, 6,330,435, 5,987,019, 6,466, 568, and 5,790,516 as asserted in the above captioned case.
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`A Markman hearing was held on June 27, 2012, to construe the disputed terms of the various
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`patents. For the reasons stated herein, the Court adopts the constructions set forth below.
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`CLAIM CONSTRUCTION PRINCIPLES
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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)(quoting Innova/Pure Water, Inc. v. Safari Water Filtration Sys., Inc., 381 F.3d 111,
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`115 (Fed. Cir. 2004)). The Court examines a patent’s intrinsic evidence to define the patented
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`invention’s scope. Id. at 1313-1314; Bell Atl. Network Servs., Inc. v. Covad Commc’ns Group, Inc.,
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`262 F.3d 1258, 1267 (Fed. Cir. 2001). Intrinsic evidence includes the claims, the rest of the
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`specification and the prosecution history. Phillips, 415 F.3d at 1312-13; Bell Atl. Network Servs.,
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`262 F.3d at 1267. The Court gives claim terms their ordinary and customary meaning as understood
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`Case 6:10-cv-00473-LED-KFG Document 341 Filed 03/08/13 Page 2 of 23 PageID #: 7575
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`by one of ordinary skill in the art at the time of the invention. Phillips, 415 F.3d at 1312-13; Alloc,
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`Inc. v. Int’l Trade Comm’n, 342 F.3d 1361, 1368 (Fed. Cir. 2003).
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`Claim language guides the Court’s construction of claim terms. Phillips, 145 F.3d at 1314.
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`“[T]he context in which a term is used in the asserted claim can be highly instructive.” Id. Other
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`claims, asserted and unasserted, can provide additional instruction because “terms are normally used
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`consistently throughout the patent.” Id. Differences among claims, such as additional limitations
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`in dependent claims, can provide further guidance. Id.
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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)). “[T]he specification
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`‘is always highly relevant to the claim construction analysis. Usually it is dispositive; it is the single
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`best guide to the meaning of a disputed term.’” Id. (quoting Vitronics Corp. v. Conceptronic, Inc.,
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`90 F.3d 1576, 1582 (Fed. Cir. 1996)); Teleflex Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1325
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`(Fed. Cir 2002). In the specification, a patentee may define his own terms, give a claim term a
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`different meaning that it would otherwise possess, or disclaim or disavow some claim scope.
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`Phillips, 415 F.3d at 1316. Although the Court generally presumes terms possess their ordinary
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`meaning, this presumption can be overcome by statements of clear disclaimer. See Sci Med Life Sys.,
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`Inc. v. Advanced Cardiovascular Sys., Inc., 242 F.3d 1337, 1343-44 (Fed. Cir. 2001). This
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`presumption does not arise when the patentee acts as his own lexicographer. See Irdeto Access, Inc.
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`v. EchoStar Satellite Corp., 383 F.3d 1295, 1301 (Fed. Cir. 2004).
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`The specification may also resolve ambiguous claim terms “where the ordinary and
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`accustomed meaning of the words used in the claims lack sufficient clarity to permit the scope of the
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`claim to be ascertained from the words alone.” Teleflex, Inc., 299 F.3d at 1325. For example, “[a]
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`claim interpretation that excludes a preferred embodiment from the scope of the claim ‘is rarely, if
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`ever, correct.” Globetrotter Software, Inc. v. Elam Computer Group, Inc., 362 F.3d 1367, 1381
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`(Fed. Cir. 2004)(quoting Vitronics Corp., 90 F.3d at 1583). But, “[a]lthough the specification may
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`aid the court in interpreting the meaning of disputed language in the claims, particular embodiments
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`and examples appearing in the specification will not generally be read into the claims.” Constant
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`v. Advanced Micro-Devices, Inc., 848 F.2d 1560, 1571 (Fed. Cir. 1988); see also Phillips, 415 F.3d
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`at 1323.
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`The prosecution history is another tool to supply the proper context for claim construction
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`because a patentee may define a term during the prosecution of the patent. Home Diagnostics, Inc.
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`v. LifeScan, Inc., 381 F.3d 1352, 1356 (Fed. Cir. 2004)(“As in the case of the specification, a patent
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`applicant may define a term in prosecuting the patent.”). The well-established doctrine of
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`prosecution disclaimer “preclud[es] patentees from recapturing through claim interpretation specific
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`meanings disclaimed during prosecution.” Omega Eng’g Inc. v. Raytek Corp., 334 F.3d 1314 (Fed.
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`Cir. 2003). The prosecution history must show that the patentee clearly and unambiguously
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`disclaimed or disavowed the proposed interpretation during prosecution to obtain claim allowance.
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`Middleton Inc. v. 3M Co., 164 F.3d 1372, 1378-79 (Fed. Cir. 1988)(quotations omitted). “As a
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`basic principle of claim interpretation, prosecution disclaimer promotes the public notice function
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`of the intrinsic evidence and protects the public’s reliance on definitive statements made during
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`prosecution.” Omega Eng’g, Inc., 334 F.3d at 1324.
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`Although, “less significant than the intrinsic record in determining the legally operative
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`meaning of claim language, “the Court may rely on extrinsic evidence to “shed useful light on the
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`relevant art.” Phillips, 415 F.3d at 1317 (quotation omitted). Technical dictionaries and treatises
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`may help the Court understand the underlying technology and the manner in which one skilled in the
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`art might use claim terms, but such sources may also provide overly broad definitions or may not be
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`indicative of how terms are used in the patent. Id. at 1318. Similarly, expert testimony may aid the
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`Court in determining the particular meaning of a term in the pertinent field, but “conclusory,
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`unsupported assertions by experts as to the definition of a claim term are not useful.” Id. Generally,
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`extrinsic evidence is “less reliable than the patent and its prosecution history in determining how to
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`read claim terms.” Id.
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`Determining the claimed function and the corresponding structure of means-plus-function
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`clauses are matters of claim construction. WMS Gaming Inc., v. Int’l Game Tech., 184 F.3d 1339,
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`1347 (Fed. Cir. 1999). Claim construction of a means-plus-function limitation involves two steps.
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`See Medical Instrumentation and Diagnostics v. Elekta, 344 F.3d 1205, 1210 (Fed. Cir. 2003). The
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`court must first identify the particular claimed function, and then look to the specification and
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`identify the corresponding structure for that function. Id. “Under this second step, ‘structure
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`disclosed in the specification is corresponding structure only if the specification or prosecution
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`history clearly links or associates that structure to the function recited in the claim.’” Id. (citations
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`omitted). “While corresponding structure need not include all things necessary to enable the claimed
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`invention to work, it must include all structure that actually performs the recited function.” Default
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`Proof Credit Card System, Inc. v. Home Depot U.S.A., Inc., 412 F.3d 1291, 1298 (Fed. Cir. 2005).
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`OVERVIEW OF THE ‘215 PATENT
`
`The ‘215 patent is entitled “Method for Minimizing Feedback Responses in ARQ Protocols”
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`and the invention relates in general to the telecommunications field and, in particular, to a method
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`for minimizing feedback responses in Automatic Repeat Request (ARQ) protocols. Data sent by a
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`transmitter (such as a wireless router) to a receiver (such as a computer) is broken into data packets
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`(also called “Protocol Data Units” or “PDUs”) which have sequence numbers. ‘215 patent at 1:29-
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`30. The receiver assembles the data packets back into the proper order using the sequence numbers.
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`In a perfect world, the receiver would receive all the data packets in the proper order. However,
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`frequently data packets get lost or corrupted during the transmission from the transmitter to the
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`receiver and never make it to the receiver’s buffer. Certain algorithms are used to recover from the
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`transmission of erroneous data and the loss of data on the transmission links between the nodes.
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`‘215 patent at 1:21-23. An algorithm commonly used to recover from the transmission of erroneous
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`data is referred to as an Automatic Repeat Request (ARQ) protocol. ‘215 patent at 1:23-25. The
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`basic function of the ARQ protocol is to allow the receiver to request that the transmitter re-transmit
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`those PDUs that were lost or contained errors during transmission. ‘215 patent at 1:34-37. The
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`PDUs that are sent from the receiver back to the transmitter include control data needed for error
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`control/recovery and are called “status PDUs” (S-PDUs).
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`Two main methods are currently used for coding the sequence numbers of the lost or
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`corrupted data within the S-PDUs sent from the transmitter back to the receiver. One method is to
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`use a list of sequence numbers to be re-transmitted. The second method is to use a bitmap to
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`represent the sequence numbers to be re-transmitted. ‘215 patent at 2:48-52. However, a significant
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`problem with the existing ARQ protocols is that they are static in construction and, in certain
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`situations, this may lead to a waste of bandwidth, because a great deal of information is transmitted
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`unnecessarily in the S-PDUs. ‘215 patent at 3:46-50.
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`Therefore, the inventors of the ‘215 patent recognized that a significant need existed for a
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`method that can be used to minimize the size of S-PDUs in an ARQ protocol and for a method that
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`can be used to maximize the number of sequence numbers in an S-PDU with limited size, if it is not
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`possible to fit all potential sequence numbers into a single S-PDU. ‘215 patent at 4:33-38. The
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`inventors summarized the invention as “a method for minimizing feedback responses in an ARQ
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`protocol ... whereby different mechanisms can be used to indicate erroneous D-PDUs and construct
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`S-PDUs. In particular, these different mechanisms can be combined in a single S-PDU. The S-
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`PDUs are constructed so as to optimize system performance in accordance with certain criteria. One
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`such criterion used is to minimize the size of the S-PDUs. A second such criterion used is to
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`maximize the number of [sequence numbers] in an S-PDU of limited size.” ‘215 patent at 4:44-53.
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`I.
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`Disputed terms of the ‘215 patent.
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`DISCUSSION
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`The disputed terms and their proposed constructions are set forth below.
`
`a.
`
`“responsive to the receiving step, constructing a message field for a second data
`unit, said message field including a type identifier field” (claims 1, 15 and 25)
`
`Plaintiffs’ Proposed Construction
`responsive to the receiving step, generating a
`message field including a field that identifies
`the message type of the feedback response
`message from a number of different message
`types
`
`Defendants’ Proposed Construction
`responsive to the receiving step, generating a
`message field including a field identifying the
`type of feedback response that is selected
`from multiple available feedback responses in
`order to minimize the size of number of
`feedback responses
`
`Plaintiffs acknowledge that the proposed constructions are nearly identical, but argue that
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`Defendants’ proposed construction contains superfluous language and should be rejected. Plaintiffs’
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`first objection to Defendants’ proposed construction is that it requires the type of feedback response
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`to be actively “selected from multiple available feedback responses”, which, they argue, would
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`import an entirely additional step (the step of selecting) into the claim, violating the canons of claim
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`construction.
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`Plaintiffs also object to Defendants’ requirement that the unclaimed “selecting” further
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`accomplish the goal of “minimiz[ing] the size or number of feedback responses.” Plaintiffs argue
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`that while minimizing the size of number of feedback responses may be the benefit of the invention,
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`not every benefit flowing from an invention is a claim limitation, citing i4i, Ltd. Partnership v.
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`Microsoft Corp., 598 F.3d 831, 843 (Fed. Cir. 2010), aff’d __U.S.__, 131 S. Ct. 2238, 180 L. Ed.
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`2d 131. They contend Defendants’ construction adds only two, and not all, of the advantages set
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`forth in the patent. According to Plaintiffs, Defendants do not point to any lexicography, disclaimer,
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`or disavowal that allow the limitations to be included in the claims and, further, the patentee
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`apparently chose to put “minimization of feedback responses” in the preamble where it is not a
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`limitation. They further argue that the claims define the invention, and that those claims do not
`1
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`include Defendants’ proposed extraneous limitations.
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`Defendants respond that their construction captures the actual inventive concept claimed to
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`overcome the prior art problems identified in the specification. They further argue that the solution
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`to the problem (the static use of a particular type of response) not addressed by the prior art is to
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`“select” a feedback response to optimize system performance. ‘215 patent at 9:12-14. They contend
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`that “selecting” or “minimizing” is already part of the claim as part of the element requiring the
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`construction of a feedback response “in response to” incoming data units. Defendants argue that this
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`is not merely some benefit of the invention, it is the invention and the claims should be construed
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` Plaintiffs contend that Defendants have never before claimed in their briefing that the preamble is a limitation
`1
`and are essentially trying to back-door it in as a limitation now. See Transcript of Claim Construction Hearing (doc.
`#255), p. 16.
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`Case 6:10-cv-00473-LED-KFG Document 341 Filed 03/08/13 Page 8 of 23 PageID #: 7581
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`to capture the scope of the actual invention, citing Retractable Techs., Inc. v. Becton, Dickinson and
`2
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`Co., 653 F.3d 1296 (Fed Cir. 2011) (citing Phillips v. AWH Corp., 415 F.3d 1303, 1323 (Fed. Cir.
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`2005)(en banc)).
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`This Court notes that there is currently a split among the judges on the Federal Circuit
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`regarding the appropriate role of the specification in construing the claims of a patent. See
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`Retractable Technologies, Inc. v. Becton, Dickinson and Company, 659 F.3d 1369 (Fed. Cir.
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`2011)(denial of re-hearing en banc). As stated above, Defendants urge that the claims should be
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`construed in order to capture the actual scope of the invention. Judge Lourie is of the view that the
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`claims are limited by the “invention” described in the specification. Retractable, 653 F.3d at 1305
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`(“In reviewing the intrinsic record to construe the claims, we strive to capture the scope of the actual
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`invention, rather than strictly limit the scope of the claim to disclosed embodiments or allow claim
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`language to become divorced from what the specification conveys is the invention.”). However,
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`Judge Moore along with Chief Judge Rader take the view that the claims define the metes and
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`bounds of the patented invention and, although the specification may shed light on the plain and
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`ordinary meaning of a claim term, it cannot be used to narrow the claim term unless the inventor
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`acted as his own lexicographer or intentionally disclaimed or disavowed claim scope. Retractable,
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`659 F.3d at 1360-71.
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`This Court is inclined toward Judge Moore’s and Chief Judge Radar’s view in Retractable.
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`Defendants’ proposed construction seems to fall on the side of reading limitations into the claims
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` Ericsson disagrees that the advantage of minimizing the feedback response is the crux of the invention. It
`2
`contends that the invention is “the creation of a choice in the receiver of multiple different formats of messages to use
`and then also the creation of a type identifier field which allows the receiver to identify to the transmitter which it is
`choosing.” Transcript, p. 13.
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`Case 6:10-cv-00473-LED-KFG Document 341 Filed 03/08/13 Page 9 of 23 PageID #: 7582
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`rather than reading the claims in light of the specification. In addition, this Court agrees with
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`Plaintiffs that Defendants’ construction adds only two, and not all, of the advantages set forth in the
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`patent. “[T]he fact that a patent asserts that an invention achieves several objectives does not require
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`that each of the claims be construed as limited to structures that are capable of achieving all of the
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`objectives.” Phillips, 415 F.3d at 1327 (internal quotations omitted).
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` Therefore, this Court finds that the term “responsive to the receiving step, constructing a
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`message field for a second data unit, said message field including a type identifier field” means
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`“responsive to the receiving step, generating a message field including a field that identifies the
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`message type of the feedback response message from a number of different message types.”
`
`b.
`
`“means for receiving said plurality of first data units, and constructing one to
`several message fields for a second data unit, said one to several message fields
`including a type identifier field and at least one of a sequence number field, a
`length field, a content field, a plurality of erroneous sequence number fields,
`and a plurality of erroneous sequence number length fields, each of said
`plurality of erroneous sequence number fields associated with a respective one
`of said plurality of erroneous sequence number length fields” (claim 45)
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` Defendants’ Proposed Construction
`Recited Function: receiving the plurality of
`first data units and generating a message field
`including a field identifying the type of
`feedback response that is selected from
`multiple available feedback responses in
`order to minimize the size or number of
`feedback responses and at least one of a
`sequence number field, a length field, a
`content field, a plurality of erroneous
`sequence number fields, and a plurality of
`erroneous sequence number length fields,
`each of said plurality of erroneous sequence
`number fields associated with a respective
`one of said plurality of erroneous sequence
`number length fields
`
`Corresponding Structure: (a) Fig. 4, Fig. 5,
`Fig. 6, Table 1, 3:6-13, 36-42, 4:1-54, 5:50-
`6:49, 6:55-64, 7:28-51
`
`(b) Invalid under Section 112, paragraphs 2,6.
`
` Plaintiffs’ Proposed Construction
`Recited Function: receiving said plurality of
`first data units, and constructing one to
`several message fields for a second data unit,
`said one to several message fields including a
`type identifier field and at least one of a
`sequence number field, a length field, a
`content field, a plurality of erroneous
`sequence number fields, and a plurality of
`erroneous sequence number length fields,
`each of said plurality of erroneous sequence
`number fields associated with a respective
`one of said plurality of erroneous sequence
`number length fields
`
`Corresponding Structure: the receiver of a
`peer entity, see ‘215:2:29-30, whereby
`different mechanisms can be used to indicate
`erroneous data units so as to optimize
`performance, see ‘215::5:53-56, and the
`mechanisms refer to any of the methods
`described for constructing a bitmap feedback
`response message disclosed at ‘215::3:17-28
`and ‘215::6:8-48, any of the methods for
`constructing a compressed bitmap feedback
`response message disclosed at ‘215::6:49-54,
`any of the methods for constructing a list
`feedback response message disclosed at
`‘215::2:63-3:16 and ‘215::7:28-51, and/or the
`method for constructing a feedback response
`message combining the list and bitmap
`methods, and any equivalents thereof.
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`Plaintiffs’ contend that their proposed function for this term is the function explicitly recited
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`in the claim and that they have identified corresponding structure that “actually performs” the recited
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`function. Plaintiffs argue that Defendants’ proposed recited function for this term is a different
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`function and therefore is legally defective. Plaintiffs note that the substantive dispute regarding this
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`term is related to a previous argument as to whether minimization or optimization is a required part
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`of the function. Plaintiffs argue that the structure set forth at 3:6-13 and 3:36-42 deal with the
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`calculation of the size of the S-PDU and has nothing to do with the actual construction of the
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`message. Likewise, they contend that Table 1 has nothing to do with constructing the feedback
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`response message.
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`Defendants agree that this debate is an extension of the initial debate, that is, what does this
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`claim capture? Defendants again contend that the essence of the invention is that there be a
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`minimization or optimization of the size or the number of the S-PDUs. Defendants argue that the
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`claimed invention cannot be something that merely constructs a S-PDU to send back to the
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`transmitter without the determination of which type of S-PDU (list, bitmap, etc.) would be optimal.
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`According to defendants, this is all over the prior art.
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`The Court finds that Plaintiffs have proposed the correct function for this means-plus-function
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`term. Although Defendants argue that the Court is not restricted to the actual language used in the
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`claim to define the function, the Federal Circuit has made it clear that “[t]he statute does not permit
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`limitation of a means plus function claim by adopting a function different from that explicitly recited
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`in the claim.” Micro Chemical, Inc. v. Great Plains Chemical Co., Inc., 194 F.3d 1250, 1258 (Fed.
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`Cir. 1999). In addition, Plaintiffs have correctly identified the “corresponding structure” disclosed
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`in the specification.
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`In a related argument, Defendants contend that claim 45 is invalid because Ericsson’s
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`proposals for corresponding structure do not include portions of the specification necessary to support
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`their interpretation of the claimed function. See Motion for Summary Judgment [Clerk’s doc. # 224,
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`p. 16]. In other words, they assert that Plaintiffs’ proposed structure is incomplete because it omits
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`portions of the specification relating to the claimed optimization. Therefore, they contend that
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`Plaintiffs’ proposed structure is incomplete, and as such does not disclose an algorithm to support its
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`construction of the “means for receiving . . .and constructing” element. During the hearing,
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`Defendants “absolutely concede[d]” that there is adequate structure disclosed in the specification and
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`that this issue is a claim construction issue and not a summary judgment indefiniteness issue. See
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`Transcript, pp. 61-62.
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`This Court agrees with Plaintiffs and finds that there is no “optimization” claimed in the
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`recited function, and it would be error to import any function other than what is explicitly recited in
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`the claim. See Micro Chem., 194 F.3d at 1258.
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`This Court finds that the recited function is: “receiving said plurality of first data units, and
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`constructing one to several message fields for a second data unit, said one to several message
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`fields including a type identifier field and at least one of a sequence number field, a length field,
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`a content field, a plurality of erroneous sequence number fields, and a plurality of erroneous
`
`sequence number length fields, each of said plurality of erroneous sequence number fields
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`associated with a respective one of said plurality of erroneous sequence number length fields.”
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`The corresponding structure is: the receiver of a peer entity, see ‘215::2:29-30, whereby
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`different mechanisms can be used to indicate erroneous data units so as to optimize
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`performance, see ‘215::5:53-56, and the mechanisms refer to any of the methods described for
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`constructing a bitmap feedback response message disclosed at ‘215::3:17-28 and ‘215::6:8-48,
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`any of the methods for constructing a compressed bitmap feedback response message disclosed
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`at ‘215::6:49-54, any of the methods for constructing a list feedback response message disclosed
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`at ‘215::2:63-3:16 and ‘215::7:28-51, and/or the method for constructing a feedback response
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`message combining the list and bitmap methods, and equivalents thereof.”
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`OVERVIEW OF THE ‘435 PATENT
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`The ‘435 patent builds on what happens after an ACK message is sent to the transmitter from
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`the receiver. As shown in the ‘215 patent, a receiver may request that the transmitter resend data
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`packets that it (the receiver) didn’t receive with an ACK message. The transmitter may continue to
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`retransmit those data packets but it may be that the receiver still may not receive the data packets due
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`to a continued corruption of the signal. The receiver may still wait on the data packets even though
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`the data may be obsolete. The transmitter continues to store these data packets in the buffer because
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`the receiver still has not acknowledged receipt of them. This causes the buffers of both the transmitter
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`and the receiver to become full and the result is that the buffers cannot receive the next group of data
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`packets. This causes unacceptable delay in real time applications such as streaming video and
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`television.
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`The ‘435 patent attempts to address this problem by using a “discard notification message.”
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`The transmitter will hold a specified number of packets in its buffer until it receives and
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`acknowledgment that the receiver got them. The receiver holds an incomplete set of packets in its
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`buffer until the complete set is received. ACK messages are sent from the receiver to the transmitter
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`and the transmitter keeps re-sending the data packets until a timer expires. The transmitter then sends
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`a discard message to the receiver which tells the receiver that the transmitter deleted the old packets
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`so they will not be resent. The receiver gets this message and then determines which packets have
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`been discarded by the transmitter. It then removes these data packets from the list of those expected
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`to be received from the transmitter. This allows the transmitter and receiver to transmit and receive
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`other data packets without having to wait on the transmission of obsolete data packets.
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`II.
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`Disputed terms of the ‘435 patent.
`
`a.
`
`“data packet discard notification message from the transmitter to the receiver
`indicating data packets the transmitter has discarded.” (claim 1)
`
`Plaintiffs’ Proposed Construction
`a control message in an Automatic Repeat
`Request Protocol that indicates data packets
`that the transmitter has discarded
`
`Defendants’ Proposed Construction
`message containing the identity of
`unacknowledged data packets the transmitter
`has discarded
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`One dispute between the parties focuses on whether the discard message must actually contain
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`the explicit identity of the discarded packets. Plaintiffs assert that it does not. Initially, Plaintiffs
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`point out that Claim 1 requires that the receiver will compute “which data packets have been
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`discarded by the transmitter based on the data packet discard notification message.” In addition,
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`Plaintiffs argue that dependent Claim 6 specifically requires that the data packet discard notification
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`message include a sequence number field for each data packet to be discarded by the receiver.
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`Plaintiffs further note that dependent Claim 3 requires that the discard message include a sequence
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`number to indicate the first data packet to be discarded and a length field to indicate a number of data
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`packets immediately preceding the first data packet, that are to be discarded by the receiver.
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`According to Plaintiffs, the use of a length field in this context shows that the message itself does not
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`explicitly indicate each packet to be discarded. Rather, the message need contain only enough
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`information for the receiver to derive, in its computing step, which packets should be discarded.
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`Defendants initially responded that “identify” carries the same meaning as “indicate”. However,
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`during the hearing, Defendants responded that they had no objection to the term “indicating”.
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`“Indicating” and “identifying” are not used interchangeably in the ‘435 patent. Forms of
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`“indicating” are used 29 times, always in the same context as the claim language. Forms of “identify”
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`were used 13 times, mostly in the context of sequence numbers “identifying” discarded cells. The
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`plain language of Claim 1 and Claim 13 show that “identifying” and “indicating” are used differently
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`in this patent. This Court agrees with Plaintiffs on this particular point. “Indicates” should be used
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`instead of “containing the identity.”
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`The second dispute focuses on whether the Defendant’s addition of the word
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`“unacknowledged” in their construction is proper. Plaintiffs note that, in the present invention, the
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`discard message is triggered by both an NACK (a negative acknowledgment from the receiver to the
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`transmitter) and in a situation where the there is no acknowledgment from the receiver to the
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`transmitter (unacknowledged). ‘435 patent at 1:14-22. The so-called NACK embodiment is
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`illustrated at 4:53-67. Plaintiffs also argue that Defendant’s addition of the word “unacknowledged”
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`in their construction reads out the preferred embodiment disclosed at 4:53-67.
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`Defendants respond that “unacknowledged” packets and “negatively acknowledged data
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`packets” refer to the same thing, that is, packets that have not been successfully received. In other
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`words, according to Defendants, “negatively acknowledged packets” are “unacknowledged packets.”
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`This Court agrees with Plaintiffs. At worst, Defendants’ construction does in fact exclude the
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`preferred embodiment set forth at 4:53-67. “A claim interpretation that excludes a preferred
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`embodiment from the scope of the claim is rarely, if ever, correct.” Globetrotter Software, Inc. v.
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`Elan Computer Group, Inc., 362 F.3d 1367, 1381 (Fed. Cir. 2004). At best, inserting
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`“unacknowledged” into the claim construction would be importing limitations into the claim which
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`is improper.
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`Finally, Defendants argue that “control message” and “Automatic Repeat Request” are
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`improper limitations to import into the claim. The Court notes that the claim calls for a “message”
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`and not a “control message.” The Court also notes that it agrees with Defendants that “in an
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`Automatic Repeat Request protocol” is not necessary language to be included in the construction or
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`helpful to the jury because of its existence in the preamble.
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`Therefore, this Court finds that the proper construction is: “a message that indicates data
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`packets that the transmitter has discarded.”
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`OVERVIEW OF THE ‘019 AND ‘568 PATENTS
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`The ‘568 patent, which contains apparatus claims, is a division of the ‘019 patent, which
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`contains method claims. Both patents contain the same specification and similar claim language.
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`Both of these patents are entitled “Multi-Rate Radiocommunication Systems and Terminals” and
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`describe ways to efficiently transmit a variety of different types of information. Different types of
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`information often have different optimal transmission characteristics. For examples, users
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`communicating by cellular telephone will desire rapid two-way communication and may not be
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`concerned with minor transmission errors. On the other hand, a user downloading email will tolerate
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`small delays