The opinion of the court was delivered by: GARRETT BROWN, District Judge
This is a case involving antitrust and patent infringement
claims. On June 12, 2003, Plaintiff Globespanvirata, Inc.
("Plaintiff") filed suit against Defendants Texas Instruments,
Inc., The Leland Stanford Junior University and its Board of
Trustees, and Stanford University OTL, LLC (collectively referred
to as "Defendants"). On July 6, 2004, Plaintiff filed an Amended
Complaint, alleging violations of antitrust laws including,
inter alia, monopolization and unlawful conspiracy in restraint
of trade in violation of the Sherman Act § 1. (Pl.'s 1st Am.
Compl.). Plaintiff also seeks a declaratory judgment of
non-infringement, invalidity and unenforceability of the patents.
(Id.). Defendants filed an Amended Answer on July 30, 2004 and
asserted counterclaims against Plaintiff. Defendants allege that
Plaintiff's products infringe three patents which are owned by
Defendants. (Defs.' Answer & Countercl.). The Court bifurcated
the case staying the antitrust phase of the litigation until
the infringement claims are resolved. Proceeding with the patent
infringement phase of this lawsuit, the parties asked this Court
to construe the disputed patent claim terms pursuant to Markman
v. Westview Instruments, Inc., 52 F.3d 967 (Fed. Cir. 1995) (en
banc), aff'd, 517 U.S. 370 (1996).
On September 2, 2004, the parties timely filed their Opening
Claim Construction briefs with the Court. Thereafter, the parties
submitted their Reply briefs on September 23, 2004.*fn1
After having reviewed the submissions and concluding that the
parties did not clearly identify the disputed claim terms and
issues, the Court requested that the parties submit a Joint Claim
Construction Chart ("Chart") clearly setting forth the disputed
issues. On January 20, 2005, the parties jointly submitted the Chart which identified a total of thirty-five disputed claim
terms, Plaintiff and Defendants' proposed constructions for each
term, and also stipulated to the construction of several other
terms. A Markman hearing was held on January 31, 2005.
There are three patents-in-suit. All of the patents relate to
the field of digital communications, specifically data
transmission using multicarrier modulation transmission systems.
The inventions represent advancements in digital subscriber line
("DSL") and asymmetric digital subscriber line ("ADSL")
technology, which enable large amounts of digital data to be
transmitted over regular telephone lines.*fn2 DSL/ADSL
technology is a key factor in the improvement of
telecommunication services one of the most notable and widely
used being high-speed Internet access. The patents are aimed at
increasing the speed and reliability of the transmission of data
in DSL/ADSL technology and other telecommunication systems.
The first patent-in-suit, U.S. Patent No. 5,479,447, is
entitled "Method and Apparatus for Adaptive, Variable Bandwidth,
High-Speed Data Transmission of a Multicarrier Signal Over
Digital Subscriber Lines." U.S. Patent No. 5,479,447 (issued Dec.
26, 1995) ("the `447 Patent"). The patent issued from the U.S.
Patent and Trademark Office ("PTO") on December 26, 1995. It
issued from Application No. 57,301, which was filed with the PTO
on May 3, 1993. Peter S. Chow and John M. Cioffi are the named
inventors. Defendant The Board of Trustees of the Leland Stanford
Junior University owns the `447 Patent. Defendant Texas Instruments,
Inc. ("TI") is an exclusive licensee who has the right to bring
an action for infringement based on this patent. The patent
discloses two principle objectives of the invention. The first is
"to provide a method and apparatus for calculating the optimal
transmission bandwidth during on-line system initialization."
`447 Patent, col. 5, ll. 32-36. The second objective is that the
method and apparatus are "real-time adaptive during normal system
operation, with continuous data transmission, to compensate for
changes in transmission medium characteristics." Id. at col. 5,
ll. 38-41. The patent describes the concept of a continuously
adaptive transmitter working in conjunction with a continuously
adaptive receiver as distinct over the prior art. Id. at col.
6, ll. 2-5.
The second patent-in-suit, U.S. Patent No. 5,400,322, is
entitled "Updating of Bit Allocations in a Multicarrier
Modulation Transmission System." U.S. Patent No. 5,400,322
(issued Mar. 21, 1995) ("the `322 Patent"). The patent issued
from the PTO on March 21, 1995. It issued from Application No.
109,489, which was filed with the PTO on August 20, 1993. Ronald
R. Hunt and Peter S. Chow are the named inventors. TI is the
owner of this patent. The object of the invention is "to provide
an improved method of updating allocations of bits to carriers in
a transmission system using multicarrier modulation." `322
Patent, col. 2, ll. 40-42. Updating bit allocations is necessary
in this type of system to respond to the varying signal-to-noise
ratios ("SNRs"), which result from changes in the temperature or
traffic on the transmission channels. The invention provides the
desirable effect of updating bit allocations to accommodate such
changes in the channels.
The third patent-in-suit, U.S. Patent No. 5,596,604, is
entitled "Multicarrier Modulation Transmission System with
Variable Delay." U.S. No. Patent 5,596,604 (issued Jan. 21, 1997)
("the `604 Patent"). The patent issued from the PTO on January
21, 1997. It issued from Application No. 107,200, which was filed with the PTO on August 17, 1993. John M.
Cioffi, Po Tong, James T. Aslanis and Antoinette H. Gooch are the
named inventors. TI also owns this patent. The invention
addresses a problem known in the art as impulse noise, which
causes errors on transmission channels. `604 Patent, col. 1, ll.
57-67. To reduce errors caused by impulse noise, the invention
employs techniques known as forward error correction coding
("FECC") and codeword interleaving. The patent contemplates the
application of these techniques in a manner that results in the
maintenance of high reliability and minimized transmission delay
for the various types of data signals. Id., col. 2, ll. 25-27.
I. LAW OF CLAIM CONSTRUCTION
The first step in a patent infringement analysis is to define
the meaning and scope of the claims of the patent. Markman v.
Westview Instruments, Inc., 52 F.3d 967, 976 (Fed. Cir. 1995)
(en banc), aff'd, 517 U.S. 370 (1996). Claim construction,
which serves this purpose, is a matter of law exclusively for the
court. Id. at 979. When construing claims, the court must first
consider the intrinsic evidence. Specifically, the focus of the
court's analysis must begin and remain on the language of the
claims, "for it is that language that the patentee chose to use
to `particularly point? out and distinctly claim? the subject
matter which the patentee regards as his invention.'"
Interactive Gift Express, Inc. v. Compuserve, Inc.,
256 F.3d 1323, 1331 (Fed. Cir. 2001) (quoting 35 U.S.C. § 112, ¶ 2).
Generally, there is a presumption that the words of a claim
will receive the full breadth of its ordinary meaning. NTP, Inc.
v. Research In Motion, Ltd., 392 F.3d 1336, 1346 (Fed. Cir.
2004). The ordinary meaning may be derived from a variety of sources
including the claim language, the written description, drawings,
the prosecution history, and dictionaries or treatises.*fn3
Id. The presumption may be rebutted if the patentee acted as
his or her own lexicographer by clearly setting forth a
definition of the claim term unlike its ordinary and customary
meaning. Brookhill-Wilk 1, LLC. v. Intuitive Surgical, Inc.,
334 F.3d 1294, 1298-99 (Fed. Cir. 2003). Any intent by the
patentee to redefine a term must be expressed in the written
description, and must be sufficiently clear. Merck & Co, Inc. v.
Teva Pharms. USA, Inc., 395 F.3d 1364, 1370 (Fed. Cir. 2005).
The presumption may also be overcome "if the inventor has
disavowed or disclaimed scope of coverage, by using words or
expressions of manifest exclusion or restriction, representing a
clear disavowal of claim scope." Brookhill-Wilk,
334 F.3d at 1299. To ascertain the true ordinary meaning of a term, one must
not refer to relevant dictionaries in isolation, but more
importantly, in the context of its surrounding text in the claim,
the written description and the prosecution history.
Brookhill-Wilk, 334 F.3d at 1300; NTP, Inc.,
392 F.3d at 1346. Such intrinsic evidence should be "examined through the
viewing glass of a person skilled in the art." Brookhill-Wilk,
334 F.3d at 1300.
In consulting dictionaries to discern the ordinary meaning,
such reference should be limited to dictionaries that are
contemporaneous with the patent. Brookhill-Wilk,
334 F.3d at 1299. Dictionaries published after the patent issued may not
accurately reflect the meaning of a term to a person of ordinary
skill in the art as of the grant of the patent, and therefore
should not be considered in a claim construction analysis. Id. If more than one possible
dictionary definition exists, the claim term may be interpreted
to encompass all definitions if they are consistent with the
usage of the term in the intrinsic record. Id. at 1300; Texas
Digital Sys., Inc. v. Telegenix, Inc., 308 F.3d 1193, 1203 (Fed.
The court may consult extrinsic evidence, including expert
opinion, to guide its comprehension of the relevant technology in
accordance with the understanding of a skilled artisan. Altiris,
Inc. v. Symantec Corp., 318 F.3d 1363, 1369 (Fed. Cir. 2003).
Such evidence, however, need not be considered by the court if it
is able to determine the ordinary meaning based on the intrinsic
evidence and appropriate dictionaries or treatises. Vitronics
Corp. v. Conceptroncs, Inc., 90 F.3d 1576, 1583 (Fed. Cir.
1996). Moreover, extrinsic evidence may not be relied upon to
contradict or vary the meaning of the term as used in the claim.
Altiris, 318 F.3d at 1369.
Lastly, the court must be mindful of the well-settled rule
"that while proper claim construction requires an examination of
the written description and relevant prosecution history to
determine the meaning of claim limitations, additional
limitations may not be read into the claims." Storage Tech.
Corp. v. Cisco Sys., Inc., 329 F.3d 823, 831 (Fed. Cir. 2003);
see also In re Donaldson Co., 16 F.3d 1189, 1195 (Fed. Cir.
1994) (noting the "general claim construction principle that
limitations found only in the specification of a patent or patent
application should not be imported or read into a
claim.").*fn4 II. THE DISPUTED CLAIM TERMS
The first seven disputed claim terms are found in Claims 1 and
2 of the `447 Patent. Claim 1, an independent claim, and Claim 2,
a dependent claim, read as follows:
1. In a multicarrier data transmission system that
transmits data continuously over dispersive, noisy
subscriber loops for digital service from a telephone
central office to a user location and corresponding
digital service between transmitters and receivers at
said user location and said central office, a method
for implementing variable transmission bandwidth as a
function of line frequencyvariable attenuation, noise
power spectrum, a set of programmed and possibly
variable carrier target bit-error-rates, and a
programmed and possibly frequency-variable transmit
power mask to improve data transmission speed or to
improve performance margin at any given transmission
speed subject to a power or power-spectral-density
constraint, said method using subcarrier-indexed
measurements of channel gains, channel noises,
desired carrier bit-error-rates, and the programmed
power mask to provide subcarrier-indexed estimates of
transmission quality and to maintain the transmission
quality at high levels, comprising the steps of:
(a) sorting the subcarrier-indexed estimates of the
transmission quality, scaled by the desired
subcarrier bit-error-rates, into an invertible
ordering for assessment of the relative data-carrying
capabilities of the subcarriers at initialization
and/or during data transmission;
(b) calculating bit and energy allocation tables for
said multicarrier data transmission system based on
the sorted subcarrier-indexed estimates for either
improving aggregate transmitted data rate as fixed
performance margin with said power or
power-spectral-density constraint, or improving
performance margin at a fixed data rate with said
power or power-spectral-density constraint;
(c) communicating said bit and energy allocation
tables between the transmitters and the receivers of
said multicarrier transmission systems; and (d) implementing said bit and energy allocation
tables in coordination between the transmitters and
the receivers during initialization of said
multicarrier transmission system and/or during
simultaneous transmission of said digital data by
said multicarrier transmission system.
2. A multicarrier transmission system as recited in
claim 1 and further comprising the steps of:
communicating changes in bit allocation by removing a
single or several bits from those bits allocated to a
carrier or subcarrier with a quality estimate below a
specified threshold and placing that bit or bits on a
second subcarrier or carriers with a quality estimate
exceeding a second specified threshold; and
coordinating the implementation of said changes in
both the transmitters and the receivers by
communication through a bidirectional overhead data
channel, said overhead data channel being
simultaneously present with the user data channel on
the same communication line.
`447 Patent, col. 12, l. 54-col. 13, l. 41.
1. "a programmed and possibly frequency-variable transmit
The first disputed claim term is found in both Claims 1 and 2.
The parties initially posed two issues before the Court
specifically, whether the term is a claim limitation and if so,
what is the proper construction. At the Markman hearing,
however, the parties agreed that the true dispute centers around
the first issue. Defendants argue that the term "a programmed and
possibly frequency-variable transmit power mask," which appears
in the preamble portion of Claim 1, is not a claim limitation and
therefore does not require construction. Plaintiff asserts that
the term is a claim limitation. As indicated at the hearing, the
Court will construe the claim term, but will reserve its decision at this juncture as to whether the term is a
limitation.*fn5 (See Tr. of Markman Hearing at 14:1-21
("Tr.")). Accordingly, the Court adopts the construction to which
the parties stipulated at the hearing. (See id. at 9:19-10:6.)
Therefore, the meaning of disputed term  "a programmed and
possibly frequency-variable transmit power mask" is "a programmed
limit on the maximum amount of power to be transmitted in each of
the several carriers which can vary by carrier."*fn6
2. "the programmed power mask"
With regard to the second disputed claim term, the parties
stipulated at the Markman hearing that if the Court determines
that the term is a claim limitation, it should be construed in
the same manner as the first disputed term. (See Tr. at 5:1-9).
The Court will likewise reserve its decision regarding the claim
limitation issue and will adopt the parties' stipulated
construction. Accordingly, disputed term  "the programmed
power mask" means "a programmed limit on the maximum amount of
power to be transmitted in each of the several carriers which can
vary by carrier."
3. "power or power-spectral-density constraint"
With regard to the third disputed claim term, Plaintiff does
not offer a proposed construction, but rather asserts that it is
indefinite and invalid. Plaintiff interprets Defendants' proposed
construction as one that is "effectively synonymous" with the
meaning of "power mask." (Pl.'s Reply at 11). Based on the claim
language and specification, Plaintiff asserts that the terms
"powerspectral-density constraint" and "power mask" cannot be
synonymous. (Pl.'s Reply at 11; Tr. at 19:15-20:5).
Plaintiff is correct. It is clear, however, that Defendants do
not propose that "power constraint" and "power mask" mean the
same thing. At the hearing, Defendants described the system as
having a "power constraint" which serves as an overall limit to
the transmitter, as well as a "power mask" which limits the power
in each individual carrier. (Tr. at 17:9-13, 18:1-2). Further,
the plain language of Claim 1 clearly differentiates between the
terms "power mask" and a "power or power-spectral-density
constraint." Moreover, the specification also differentiates
between these terms:
When given a set of initial SNR estimates of the
orthogonal carriers of a multicarrier communication
system, a set of target bit error rates for the
carriers, and an arbitrary transmit power mask
together with an overall transmit power constraint,
the present invention provides a method of
determining the initial bit and energy allocations,
and therefore the corresponding bandwidth.
`447 Patent, col. 7, ll. 11-17 (emphases added). Therefore, these
terms are not interchangeable.
Regarding the proper construction of "power or
power-spectral-density constraint," Defendants propose that the
term should be read in the disjunctive. Specifically, Defendants
argue that the transmitter is subject to either a "power
constraint" ora "power-spectral-density constraint."*fn7
(Tr. at 16:13-24). A plain reading of the claim language supports
this proposition. Defendants submit that "power constraint"
refers to "an absolute limit on the transmitter power," and
"powerspectral-density constraint" is "one that may vary by
frequency." (Id.). Defendants noted at the hearing that this definition for "power constraint" directly
originates from the specification. The basis of Defendants'
definition for "power-spectral-density constraint," however, is
The Court agrees with Defendants' construction of "power
constraint" as a limit of maximum power based on the
specification. A preferred embodiment of the invention, as
explained in the specification, describes an algorithm associated
with the initialization procedure. This states that the
mathematical term Etarget equals the "total input energy, or
power constraint at the transmitter," and Emaxj is the
"maximum energy, or power, allowable in [a] carrier due to the
transmit power mask." `447 Patent, col. 8, ll. 17-22; col. 9, ll.
49-54. Thus, it appears that Etarget is the maximum amount of
energy at the transmitter and Emaxj is the maximum energy
that can be used by each individual carrier. Additionally, the
specification states that "in no event is [Etarget/k (k
being the number of used carriers)] greater than the allowable
amount of individual carrier transmit energy due to the power
mask." `447 Patent, col. 8, ll. 25-27. This description comports
with Defendants' proposed construction for "power constraint."
The Court is then left to determine the proper construction of
"power-spectral-density constraint." In defining this term, the
record is limited to several dictionary definitions cited by
Defendants, the claim language, specification, and the opinion of
Defendants' expert, Tim A. William, Ph.D. ("Dr. Williams").
Defendants' proffered construction is based on a series of
dictionary definitions. Such definitions, however, are taken from
dictionaries that were published well after the patent issued.
The Federal Circuit noted that reliance on dictionaries and
treatises should be limited to those that are contemporaneous
with the patent. Brookhill-Wilk, 334 F.3d at 1299 (declining
consideration of references published after the date of the
patent grant because they did not reflect the definitions that
would have been given to them by a person of ordinary skill in
the art). In the present case, the `447 Patent was filed in May 1993
and issued in December 1995. Defendants submitted references
dated between 1998 and 2004. As such, the Court will not consider
these references in its claim construction analysis.
The claim language and specification is devoid of a clear
meaning for "power-spectraldensity constraint." As a result, the
Court is left with the expert opinion of Dr. Williams for insight
as to how a skilled artisan would interpret this term. Dr.
Williams opines that a person of ordinary skill in the digital
communications field would interpret "power-spectral-density
constraint" to mean "a limit for the maximum transmit power
allowed at particular frequencies." (Williams Report, ¶ 140). In
light of the absence of contradictory evidence in the claims and
the specification, the Court will accept Dr. Williams' opinion as
indicative of the proper construction.
Therefore, based on the evidence set forth in the record, the
Court will adopt Defendants' proposed construction for this term.
Accordingly, disputed term  "power or power-spectraldensity
constraint" means "an absolute limit in the transmitter power or
a limit in maximum transmit power allowed at particular
4. "subcarrier-indexed estimates of transmission quality"
The next disputed term appears in both the preamble and body of
Claim 1. The issue presented with respect to this term is whether
the "subcarrier-indexed estimates of transmission quality" must
be measured by the four factors appearing in the preamble, namely
channel gains, channel noises, desired carrier bit-error-rates,
and the programmed power mask. (See Tr. at 24:1-19, 28:8-20).
Plaintiff contends that this term is a claim limitation because
the antecedent basis for the term appearing in the body of the claim, specifically in step (a), is
derived from the term in the preamble. `447 Patent, col. 13, ll.
2-6. At the hearing, Plaintiff introduced the prosecution history
for the `447 Patent in support of its proposition.*fn8 The
prosecution history shows that Claims 1 through 15 of the `447
Patent were initially rejected by the PTO under 35 U.S.C. § 112.
The PTO indicated that the original term that appeared in the
body of the claim, namely "the measured subscriber channel
quality estimates," lacked a clear antecedent basis. See Office
Action dated June 21, 1994 at 2. In response to the Office
Action, the patentees amended the claim by adding
"subcarrier-indexed estimates of the transmission quality" to
both the preamble and body of the claim.
Unfortunately, what the PTO's reaction was to that amendment
remains a mystery. Did the PTO allow the claims, recognizing that
the amendment added sufficient specificity to the claims? Or, did
the PTO require more? Because Plaintiff failed to submit the
complete prosecution history, the Court does not know the answer
to these simple, but potentially dispositive questions.
Nonetheless, assuming arguendo the answer to the first question
is in the affirmative, Plaintiff then argues that the method
encompassed by Claim 1 incorporates the limitations associated
with the term as set forth in the preamble. Plaintiff
characterizes this as a "clear prescribed method ? for
determining sub-carrier quality estimates." (Tr. at 28:8-10).
Thus, Plaintiff argues that the claim requires the estimates of
transmission quality be determined "by reference to channel
gains, channel noises, desired carrier bit-error-rates, and the
programmed power mask." (Tr. at 28:17-20; see also Chart at 2).
Conversely, Defendants argue that the claim does not require
the estimates to be based on these four factors. Rather,
Defendants assert that the subcarrier-indexed estimates may be
measured using a variety of methods, some of which may include
all or none of the factors listed in the preamble. According to
Defendants, estimates may be measured simply by SNRs. Defendants
contend that the specification clearly supports their argument.
It states the following:
When given a set of initial SNR estimates of the
orthogonal carriers of a multicarrier communication
system, a set of target bit error rates for the
carriers, and an arbitrary transmit power mask
together with an overall transmit power constraint,
the present invention provides a method of
determining the initial bit and energy allocations,
and therefore the corresponding transmission
`447 Patent, col. 7, ll. 10-17 (emphasis added). Defendants argue
that nothing in the specification suggests that the "set of
initial SNR estimates" must be measured by channel gains, channel
noises, desired carrier bit-error-rates, and the programmed power
mask factors which only appear in the preamble.
This Court agrees with Defendants. Generally, a preamble is a
limitation of the invention if it "recites essential structure or
steps, or if it is necessary to give life, meaning, and vitality
to the claim." Catalina Mktg. Int'l v. Coolsavings.com, Inc.,
289 F.3d 801, 808 (Fed. Cir. 2002) (quotations omitted). However,
if the patentee's use of the preamble merely states an intended
purpose or use, and the patentee defined a structurally complete
invention in the body of the claim, the preamble is not limiting.
Id. Furthermore, although claim scope may be limited if a
particular disputed term derives antecedent basis from the
preamble, the Court's determination must be based on an
examination of the patent as a whole, "to gain an understanding
of what the inventors actually invented and intended to encompass by the claim." Id. (citing
Corning Glass Works v. Sumitomo Elec. U.S.A., Inc.,
868 F.2d 1251, 1257 (Fed. Cir. 1989).
This Court concludes that "subcarrier-indexed estimates of
transmission quality" need not be measured by any of the four
factors listed in the preamble. Although the prosecution history
suggests that the claim was amended to include an antecedent
basis in the preamble for the disputed term, this alone does not
support Plaintiff's contention that the claim should be read to
require the four factors. Simply because the term appears in the
preamble, the Court is not required to import all the words
surrounding the term. Plaintiff has not cited any case law that
would suggest otherwise. Additionally, and perhaps more
importantly, the claim language itself, specifically the language
contained in Claims 5 and 6, indicate that subcarrier quality
estimates may be made "through the computation of an average
signal-to-noise measure on a subcarrier . . . [or] . . . the
computation of an average signal-to-noise ratio multiplied by a
subcarrier dependent programmed reliability factor. . . ." `447
Patent, col. 13, l. 65 col. 14, l. 10. Thus, the claims
themselves demonstrate that subcarrier-indexed estimates of
transmission quality need not be measured by four factors, but
may be measured, for example, through the computation of SNRs.
This comports with Defendants' assertion.
Furthermore, one of the preferred embodiments described in the
specification shows why Plaintiff's argument is incorrect. The
preferred embodiment describes an algorithm consisting of several
steps involved in the initialization procedure. `447 Patent, col.
7, l. 35 col. 8, l. 56. The first step involves computing SNR
estimates, or estimates of transmission quality. The fifth step
involves the maximum energy allowable in the carrier as defined
by the power mask. Plaintiff's requirement that the estimates be
measured based on, among other things, the power mask would
effectively exclude this preferred embodiment from the claim scope, since it
is not until after the calculation of estimates that the power
mask comes into play.
As the Federal Circuit has articulated, "a claim construction
that would exclude the preferred embodiment `is rarely, if ever,
correct and would require highly persuasive evidentiary
support.'" Rexnord Corp. v. Laitram Corp, 274 F.3d 1336, 1342
(Fed. Cir. 2001) (quoting Vitronics Corp. v. Conceptronic,
Inc., 90 F.3d 1576, 1583 (Fed. Cir. 1996)). Plaintiff has not
shown sufficient evidence to support its narrow construction.
Accordingly, it must be rejected. Therefore, this Court concludes
that disputed term  "subcarrier-indexed estimates of
transmission quality" does not require that the measurements of
the estimates be determined by any of the four factors enumerated
in the preamble.
5. "sorting the subcarrier-indexed estimates of the
transmission quality, scaled by the desired subcarrier
bit-error-rates, into an invertible ordering"*fn9
The dispute with respect to this term concerns the proper
meaning of "sorting." Plaintiff submits that this term means
"reordering the subcarrier-indexed estimates of the transmission
quality, which have been scaled by the desired subcarrier
bit-error-rates, into an arrangement of transmission quality
estimates that is capable of being put back into the original
subcarrier-indexed order." (Chart at 2). In essence, Plaintiff
argues that the term "sorting" as used in the claim means
"reordering" or "sorting into a new order." (Pl.'s Opening Br. at
Plaintiff relies on the claim language and the opinion of its
expert, Dirk Hartogs, Ph.D. ("Dr. Hartogs"). Dr. Hartogs opines
that a person of ordinary skill in the art would understand "that
the term `sorting' as used in Claim 1 requires a re-ordering of the
subcarrier-indexed estimates of transmission quality for each
carrier." (Hartogs Report, ¶ 41). Dr. Hartogs heavily relies upon
an example of the invention as illustrated in the preferred
embodiment. It states: "[s]ort the resulting SNR(i)/'(i)'s into
descending order and label them. . . . The mapping from the
original carrier labels to the sorted carrier labels is stored
and is invertible." `447 Patent, col. 7, ll. 49-52; col. 8, l. 65
col. 9, l. 1. Based on this disclosure, Dr. Hartogs suggests
that a person of ordinary skill in the art would understand "that
the result of the sort is an ordering of estimates from the
highest to the lowest." (Hartogs Report, ¶ 42).
Conversely, Defendants argue that the claim does not require a
reordering of the data. Defendants contend that the term is used
in a manner that is consistent with its ordinary and customary
meaning. (Defs.' Opening Br. at 33-34.) Defendants offer a
general definition of the word "sort" from Webster's New World
Dictionary. According to this reference, "sort" means "to arrange
according to class or kind." WEBSTER'S NEW WORLDDICTIONARY 563
(1995). Defendants also provide a technical definition for "sort"
from the International Organization for Standardization. In this
reference, "sort" means "[t]o segregate items into groups
according to specified criteria without necessarily ordering
the items within each group." INT'L ORG.FORSTANDARDIZATION, ISO
2382-6 Info. Processing Sys. Vocabulary Part 6: Preparation
and Handling of Data 10 (2d ed. 1987) (emphasis in original).
This Court agrees that the term "sorting" does not require
reordering of the data. The ordinary meaning of the word "sort"
suggests that mere placing or arranging into a class is
sufficient. Although the claim uses the words "sorting . . . into
an invertible ordering," Plaintiff's construction rests on the
incorrect assumption that "invertible ordering" is synonymous
with a "new order." This assumption is unsupported. The word "invertible" does not mean
"new." The plain meaning of the word "invert" means "to reverse
the order, position, direction . . . of." WEBSTER'S NEW WORLD
DICTIONARY 313 (1995). Thus, something that is "invertible" is
something that is capable of being reversed in order, position or
direction thereof. Consequently, an "invertible ordering" is an
ordering capable of being reversed, not necessarily a new order.
The Court concludes that the preferred embodiment should not
limit the meaning of the term. To sort the estimates into a
"descending order," as described in the preferred embodiment, is
only one example of how the estimates may be "sorted." To adopt
the requirement that the estimates must be "sorted," and thus
"reordered," on this basis would violate the general prohibition
against importing a limitation from the specification into the
claims. See Storage Tech. Corp. v. Cisco Sys., Inc.,
329 F.3d 823, 831 (Fed. Cir. 2003). Therefore, Plaintiff's construction
must be rejected.
Accordingly, the Court concludes that disputed term 
"sorting the subcarrier-indexed estimates of the transmission
quality, scaled by the desired subcarrier bit-error-rates, into
an invertible ordering" requires mere "sorting" of the estimates,
i.e., segregating the estimates into groups based on specified
criteria, and does not require reordering.
The parties stipulated at the Markman hearing that "scaled"
means "changed by a factor." (Tr. at 45:22). Consequently, the
Court adopts that construction. 7. "(b) calculating bit and energy allocation tables for
said multicarrier data transmission system based on the sorted
The issue presented with respect to the next disputed term
concerns the order in which the steps of the claim must be
performed. Plaintiff argues that step (a), the sorting step, must
occur before step (b), the calculating step. Plaintiff contends
that the plain language of Claim 1, and the interconnection of
each step, indicate an implicit requirement that the steps occur
in a particular order. (Pl.'s Opening Br. at 9). Specifically,
Plaintiff asserts that the calculating step must occur after the
sorting step because the calculation of bit and energy allocation
tables are "based on the sorted subcarrier-indexed estimates."
`447 Patent, col. 13, ll. 11-12 (emphasis added). Plaintiff
asserts that something must be in existence before anything can
be "based on" it. (Tr. at 47:20-24). Conversely, Defendants
contend that the claim does not require a particular order of
steps. Citing Altiris, Inc. v. Symantec Corp., 318 F.3d 1363,
1369 (Fed. Cir. 2003), Defendants argue that if a claim recites
steps, but not an order, there is a presumption that the sequence
of steps is not required.
In Altiris, the Federal Circuit explained, "[u]nless the
steps of a method actually recite an order, the steps are not
ordinarily construed to require one. However, such a result can
ensue when the method steps implicitly require that they be
performed in the order written." Id. at 1369 (quoting
Interactive Gift Express, Inc. v. Compuserve Inc.,
256 F.3d 1323 (Fed. Cir. 2001)). There is a twopart inquiry for
determining whether a method claim, which does not recite a
specific order, must be carried out in the order in which it is
First, we look to the claim language to determine if,
as a matter of logic or grammar, [the steps] must be
performed in the order written. . . . If not, we next
look to the rest of the specification to determine
whether it directly or implicitly requires such a
narrow construction. If not, the sequence in which
such steps are written is not a requirement. Id. (quotations omitted). In Altiris, the Federal Circuit
concluded that the trial court erred by imposing a limitation on
a method claim that required the steps to be performed in a
particular order. Id. at 1371. The court concluded that nothing
in the claim language logically or grammatically indicated that
the "setting step" of the method had to be performed in a
specific order. The court further concluded that the written
description did not contain any statements concerning the
importance of the order of steps, or any evidence disclaiming any
order of steps. Id.
In the present case, the Court likewise concludes that the
steps of Claim 1 and 2 need not be performed in the order in
which the steps are written. First, the Court does not find
support in the claim language supporting such a narrow
construction. Although the words "based on" suggest that the
calculation of the bit and energy tables are determined only
after the estimates are sorted, Plaintiff's proposed construction
would impose an absolute requirement that step (b) occurs after
step (a) at all times. The plain language of the claim does not
indicate that this is always the case.
Second, the written description does not support a narrow
construction. As the court found in Altiris, here there are no
statements in the specification suggesting that the method must
be performed in the way Plaintiff proposes, nor are there
statements indicating that the method would not work if the
"calculating step" is performed before the "sorting step." While
Plaintiff's argument focuses on events occurring in one
subcarrier, the specification describes a dynamic system in which
multiple carriers are acting in concert. For example, the
Another objective of the present invention is to
provide a method and apparatus that is also real-time
adaptive during normal system operation, with
continuous data transmission, to compensate for
changes in transmission medium characteristics.
`447 Patent, col. 5, ll. 37-41. Additionally, Claim 16 describes
"a multicarrier transmission system having transmitters and receivers to transmit and receive data
continuously over communication lines." `447 Patent, col. 20, ll.
27-29. Thus, it is possible that "the calculating step" is being
performed before "the sorting step" at any given time.
Plaintiff relies on the preferred embodiments, or algorithms in
the specification, in support of its argument that the steps must
occur in a particular order. (Hartogs Report, ¶ 43). Once again,
however, limitations appearing in the preferred embodiment should
not be imported into the claims themselves without justification.
See Storage Tech. Corp. v. Cisco Sys., Inc., 329 F.3d 823, 831
(Fed. Cir. 2003). As explained above, the Court finds no
Accordingly, with regard to disputed term , the Court
construes the claim as not requiring that steps (a) and (b) be
performed in any particular order.
8. The Remaining Disputed Claim Terms of the `447 Patent
The remaining terms of the `447 Patent concern
means-plus-function limitations, and therefore will be analyzed
together. Means-plus-function terms are governed by
35 U.S.C. § 112, ¶ 6. This section provides that:
[a]n element in a claim for a combination may be
expressed as a means or step for performing a
specified function without the recital of structure,
material, or acts in support thereof, and such claim
shall be construed to cover the corresponding
structure, material, or acts described in the
specification and equivalents thereof.
35 U.S.C. § 112, ¶ 6 (Thomson/West 2005). This statutory
provision allows patentees to "claim an element of a combination
functionally, without reciting structures for performing these
functions." Apex, Inc. v. Raritan Computer, Inc.,
325 F.3d 1364
,1371 (Fed. Cir. 2003). In exchange for the convenience of
employing § 112, ¶ 6, the patentee must disclose structure in the
specification that is clearly linked or associated with the claimed function. Budde
v. Harley Davidson, Inc., 250 F.3d 1369
, 1377 (Fed. Cir. 2001).
In construing a means-plus-function claim limitation, the court
must engage in a two-part inquiry. Id. at 1376. First, the
court must identify the particular function that is claimed.
Id. Second, the court must determine the corresponding
structure that performs the claimed function. Id. Failure to
disclose adequate corresponding structure renders the claim's
scope indefinite, and therefore invalid under § 112, ¶ 2. Id. A
finding that a claim containing a means-plus-function limitation
lacks structural support must be supported by clear and
convincing evidence that the specification does not disclose
structure sufficient to perform the recited function. Id. at
1376-77. Such a determination must be made from the viewpoint of
a skilled artisan. Id. at 1376.
In determining whether § 112, ¶ 6 applies to a particular claim
term, the use of the word "means" is central to the court's
analysis. Generally, the use of the word "means" creates the
presumption that § 112, ¶ 6 does apply, whereas the absence of
the word "means" creates the presumption that it does not apply.
Personalized Media Communications, LLC v. Int'l Trade Comm'n,
161 F.3d 696, 703-04 (Fed. Cir. 1998). The presumption may be
rebutted by the intrinsic and extrinsic evidence. The court
should focus its inquiry on whether "the claim as properly
construed recites sufficiently definite structure to avoid the
ambit of § 112, ¶ 6." Id. at 704. Moreover, the court should
inquire as to whether the term has a "reasonably well understood
meaning in the art." Apex, Inc., 325 F.3d at 1372 (Fed. Cir.
2003) (quoting Greenberg v. Ethicon Endo-Surgery, Inc.,
91 F.3d 1580, 1583 (Fed. Cir. 1996).
In the present case, the disputed terms are found in Claims 11
and 12 of the `447 Patent. Claim 11, an independent claim, and
Claim 12, a dependent claim, read as follows: 11. A multicarrier communication system comprising: a
 transmitter means and a  receiver
means communicatively linked together by a datalink,
the signal carrying characteristics of which are
randomly variable, said  transmitter means
means for establishing a plurality of frequency
domain subchannels for respectively communicating
various quantities of data bits selected from a
stream of data bits;
 means for measuring the capability of the
datalink to efficiently communicate the data bits in
each said subchannel and for developing an optimum
energy allocation and an optimum data bit allocation
for each said subchannels; and
means for causing an input data stream to be divided
and modulated onto a plurality of frequency domain
carriers, each corresponding to one of said
subchannels for transmission over said datalink to
said  receiver means, the quantity of data bits
transmitted over each said subchannel being selected
as a function of said optimum data bit allocation and
said  receiver means including,
means for monitoring the quality of the transmission
over each said subchannels; and
 means for returning an indication of the
monitored quality to said  transmitter means.
12. A multicarrier communication system as recited in
claim 11 wherein said  transmitter means
 means responsive to said indication of
monitored quality and operative to change the data
bit allocation among said subchannels to improve the
quality of the transmission.
`447 Patent, col. 14, l. 58 col.15, l. 26 (emphases added).
The parties disagree as to whether the terms "transmitter
means" and "receiver means" are subject to 35 U.S.C. § 112, ¶ 6.
Defendants argue that these terms do not have associated
corresponding functions, and therefore do not invoke the
presumption of means-plus-function under § 112, ¶ 6. It is Defendants' position that "transmitter means"
and "receiver means" actually refer to a "transceiver containing
a transmitter and a receiver," similar to the central office
transceiver 27, or customer premises transceiver 28, which are
depicted in Figure 5a of the patent. (Chart at 4-5). Conversely,
Plaintiff argues that "transmitter means" and "receiver means,"
as first used in the claim, are associated with the means
enumerated after the ...