Intellectual Ventures I LLC et al v. AT & T Mobility LLC et al

Filing 378

MEMORANDUM OPINION re claim construction. Signed by Judge Leonard P. Stark on 8/12/16. Associated Cases: 1:13-cv-01668-LPS et al. (ntl)

IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF DELAWARE
INTELLECTUAL VENTURES I LLC,
Plaintiff,
C.A. No. 13-1668-LPS

v.
AT&T MOBILITY LLC; AT&T
MOBILITY II LLC; and NEW
CINGULAR WIRELESS SERVICES,
INC.,
Defendants,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.
INTELLECTUAL VENTURES I LLC,
Plaintiff,

C.A. No. 13-1669-LPS

V.

LEAP WIRELESS INTERNATI ONAL,
INC. and CRICKET
COMMUNICATIONS, INC. ,
Defendants,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.

INTELLECTUAL VENTURES I LLC,
Plaintiff,
C.A. No. 13-1670-LPS

v.
NEXTEL OPERATIONS, INC. and
SPRINT SPECTRUM L.P .,
Defendants,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.
INTELLECTUAL VENTURES I LLC,
Plaintiff,
v.

T-MOBILE USA, INC. and T-MOBILE
US , INC. ,
Defendants,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.

C.A. No. 13-1671-LPS

INTELLECTUAL VENTURES I LLC,
Plaintiff,
C.A. No. 13-1672-LPS

v.
UNITED STATES CELLULAR
CORPORATION,
Defendant,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.
INTELLECTUAL VENTURES II LLC,
Plaintiff,
V.

AT&T MOBILITY LLC; AT&T
MOBILITY II LLC; and NEW
CINGULAR WIRELESS SERVICES,
INC.,
Defendants,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.

C.A. No. 14-1229-LPS

INTELLECTUAL VENTURES II LLC,
Plaintiff,
C.A. No. 14-1230-LPS

v.
LEAP WIRELESS INTERNATIONAL,
INC. and CRICKET
COMMUNICATIONS, INC. ,
Defendants,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.
INTELLECTUAL VENTURES II LLC,
Plaintiff,
v.
NEXTEL OPERATIONS, INC. and
SPRINT SPECTRUM L.P .,
Defendants,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.

C.A. No . 14-1231-LPS

INTELLECTUAL VENTURES II LLC,
Plaintiff,
C.A. No. 14-1232-LPS

v.
T-MOBILE USA, INC. and T-MOBILE
US, INC.,
Defendants,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.
INTELLECTUAL VENTURES II LLC,
Plaintiff,

C.A. No. 14-1233-LPS

v.

UNITED STATES CELLULAR
CORPORATION,
Defendant,
and
ERICSSON INC. AND
TELEFONAKTIEBOLAGET LM
ERICSSON
Intervenors.
Brian E. Farnan, Joseph J. Farnan, III, Michael J. Farnan, FARNAN LLP, Wilmington, DE
Martin J. Black, DECHERT LLP, Philadelphia, PA
Jeffrey B. Plies, DECHERT LLP, Austin, TX
Stephen J. Akerley, Justin F. Boyce, James D. Ragon, DECHERT LLP, Mountain View, CA
Attorneys for Plaintiffs.

Jennifer Ying, Jack B. Blumenfeld, Karen Jacobs, MORRIS , NICHOLS , ARSHT & TUNNELL
LLP , Wilmington, DE
Attorneys for Defendants AT&T Mobility LLC, AT&T Mobility II LLC, New Cingular
Wireless Services, Inc. , Cricket Communications, Inc. , Nextel Operations, Inc. , Sprint
Spectrum, L.P., T-Mobile USA, Inc. , T-Mobile US, Inc., United States Cellular
Corporation and Intervenor Ericsson, Inc.

Douglas M. Kubehl, Ross G. Culpepper, Johnson K. Kuncheria, Jeffrey S. Becker, Steven Jugle,
Megan LaDriere, Harrison Rich, BAKER BOTTS LLP, Dallas, TX
Joseph D. Gray, BAKER BOTTS LLP, Austin, TX
Attorneys for Defendants United States Cellular, T-Mobile USA, Inc., and T-Mobile US,
Inc., and Intervenors Ericsson Inc. and Telefonaktiebolaget LM Ericsson.

Brian C. Riopelle, David E. Finkelson, MCGUIRE WOODS LLP, Richmond, VA
Franklin D. Kang, MCGUIRE WOODS LLP , Los Angeles, CA
Attorneys for Defendants Nextel Operations, Inc. and Sprint Spectrum, L.P .

Asim M. Bhansali, David J. Silbert, Justina K. Sessions, R. Adam Lauridsen, KEKER & VAN
NEST LLP, San Francisco, CA
Attorneys for Defendants T-Mobile USA, Inc. and T-Mobile US , Inc.

Josh A. Krevitt, Benjamin Hershkowitz, GIBSON, DUNN & CRUTCHER LLP, New York, NY
Frederick S. Chung, GIBSON, DUNN & CRUTCHER LLP, Palo Alto, CA
Attorneys for Defendants Cricket Communications, Inc. , AT&T Mobility LLC, AT&T
Mobility II LLC and New Cingular Wireless Services, Inc.

MEMORANDUM OPINION

August 12, 2016
Wilmington, Delaware

Plaintiffs Intellectual Ventures I LLC and Intellectual Ventures II LLC ("Plaintiffs") filed
this patent infringement suit against AT&T Mobility LLC, AT&T Mobility II LLC, New
Cingular Wireless Services, Inc. , Cricket Communications, Inc., Nextel Operations, Inc. , Sprint
Spectrum L.P., T-Mobile USA, Inc. , T-Mobile US , Inc. , and United States Cellular Corporation
(collectively, "Defendants") on October 7, 2013. (D.I. 1) 1 Pending is the issue of claim
construction for several disputed terms in the patents-in-suit: U.S. Patent No. 5,602,831 ("the
' 831 patent"), U.S . Patent No. 6,952,408 ("the '408 patent"), U.S. Patent No. 6,640,248 ("the
' 248 patent"), U.S . Patent No. 7,385 ,994 ("the ' 994 patent"), and U. S. Patent No. 7,787,431 ("the
'431 patent").2
The parties submitted a joint claim construction brief ("JCCB") on March 9, 2016. (D.I.
208) The Court held a claim construction hearing on April 4, 2016. (D.I. 239) ("Tr.") After the
hearing, the Court ordered additional briefing regarding the ' 408 patent (D.I. 226), which was
completed on April 25, 2016 (D.I. 230, 232, 236, 237).

1

All references to the Docket Index ("D.I.") are to C.A. No. 13-1668.

2

The patents can be found in the record at D.I. 175 . While claim construction was
pending, the Patent Trial & Appeal Board (PTAB) invalidated two of the patents that had been
included in the claim construction briefing for this case: U.S. Patent Nos. 6,370, 153 and
5,963 ,557. (See D.I. 216) Subsequently, the parties indicated that the Court did not need to
consider those patents during claim construction. (D .I. 221 )
1

I.

LEGAL ST AND ARDS

Claim construction is a question oflaw. See Teva Pharm. USA, Inc. v. Sandoz, Inc., 135
S. Ct. 831, 837 (2015) (citing Markman v. Westview Instruments, Inc., 517 U.S. 370, 388-91
(1996)). "It is a bedrock principle of patent law that the claims of a patent define the invention to
which the patentee is entitled the right to exclude." Phillips v. A WH Corp., 415 F .3d 1303, 1312
(Fed. Cir. 2005) (internal quotation marks omitted). "[T]here is no magic formula or catechism
for conducting claim construction." Id. at 1324. Instead, the court is free to attach appropriate
weight to sources "in light of the statutes and policies that inform patent law." Id.
"[T]he words of a claim are generally given their ordinary and customary meaning ....
[This is] the meaning that the term would have to a person of ordinary skill in the art in question
at the time of the invention, i.e. , as of the effective filing date of the patent application." Id. at
1312-13 (internal citations and quotation marks omitted). "[T]he ordinary meaning of a claim
tern1 is its meaning to the ordinary artisan after reading the entire patent." Id. at 1321 (internal
quotation marks omitted). The patent specification "is always highly relevant to the claim
construction analysis. Usually, it is dispositive; it is the single best guide to the meaning of a
disputed term." Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996).
While "the claims themselves provide substantial guidance as to the meaning of particular
claim terms," the context of the surrounding words of the claim also must be considered.
Phillips, 415 F.3d at 1314. Furthermore, "[o]ther claims of the patent in question, both asserted
and unasserted, can also be valuable sources of enlightenment . .. [b ]ecause claim terms are
normally used consistently throughout the patent .... " Id. (internal citation omitted).

2

It is likewise true that "[d]ifferences among claims can also be a useful guide .... For
example, the presence of a dependent claim that adds a particular limitation gives rise to a
presumption that the limitation in question is not present in the independent claim." Id. at 131415 (internal citation omitted).
It is also possible that "the specification may reveal a special definition given to a claim
term by the patentee that differs from the meaning it would otherwise possess. In such cases, the
inventor' s lexicography governs. " Id. at 1316.
It bears emphasis that " [e]ven when the specification describes only a single embodiment,
the claims of the patent will not be read restrictively unless the patentee has demonstrated a clear
intent to limit the claim scope using words or expressions of manifest exclusion or restriction."

Liebel-Flarsheim Co. v. Medrad, Inc. , 358 F.3d 898, 906 (Fed. Cir. 2004) (internal quotation
marks omitted).

In addition to the specification, a court "should also consider the patent' s prosecution
history, if it is in evidence." Markman v. Westview Instruments, Inc., 52 F.3d 967, 980 (Fed. Cir.
1995), aff'd, 517 U.S. 370 (1996). The prosecution history, which is " intrinsic evidence,"
"consists of the complete record of the proceedings before the PTO [Patent and Trademark
Office] and includes the prior art cited during the examination of the patent." Phillips, 415 F.3d
at 1317. "[T]he prosecution history can often inform the meaning of the claim language by
demonstrating how the inventor understood the invention and whether the inventor limited the
invention in the course of prosecution, making the claim scope narrower than it would otherwise
be." Id.

3

In some cases, "the district court will need to look beyond the patent' s intrinsic evidence
and to consult extrinsic evidence in order to understand, for example, the background science or
the meaning of a term in the relevant art during the relevant time period." Teva, 135 S. Ct. at
841. Extrinsic evidence "consists of all evidence external to the patent and prosecution history,
including expert and inventor testimony, dictionaries, and learned treatises." Markman, 52 F.3d
at 980. For instance, expert testimony can be useful "to ensure that the court's understanding of
the technical aspects of the patent is consistent with that of a person of skill in the art, or to
establish that a particular term in the patent or the prior art has a particular meaning in the
pertinent field." Id. Nonetheless, courts must not lose sight of the fact that "expert reports and
testimony [are] generated at the time of and for the purpose of litigation and thus can suffer from
bias that is not present in intrinsic evidence." Id. Overall, while extrinsic evidence "may be
useful" to the court, it is "less reliable" than intrinsic evidence, and its consideration "is unlikely
to result in a reliable interpretation of patent claim scope unless considered in the context of the
intrinsic evidence ." Id. at 1318-19. Where the intrinsic record unambiguously describes the
scope of the patented invention, reliance on any extrinsic evidence is improper. See Pitney
Bowes, Inc. v. Hewlett-Packard Co. , 182 F.3d 1298, 1308 (Fed. Cir. 1999) (citing Vitronics , 90

F.3d at 1583).
Finally, " [t]he construction that stays true to the claim language and most naturally aligns
with the patent' s description of the invention will be, in the end, the correct construction."
Renishaw PLC v. Marposs Societa ' per Azioni, 158 F.3d 1243, 1250 (Fed. Cir. 1998). It follows

that "a claim interpretation that would exclude the inventor' s device is rarely the correct
interpretation." Osram GmbH v. Int 'l Trade Comm 'n, 505 F.3d 1351 , 1358 (Fed. Cir. 2007)
4

(quoting Modine Mfg. Co. v. United States Int'! Trade Comm 'n, 75 F.3d 1545, 1550 (Fed. Cir.
1996)).
II.

PERSON OF ORDINARY SKILL IN THE ART
The parties do not agree on who a person of ordinary skill in the art ("POSA") would be

in the context of the patents-in-suit. Plaintiffs contend that a POSA "would have been a person
with a bachelor's degree in electrical engineering, computer engineering, or computer science
with 3-4 years' experience in communications" or, alternatively, "would have a master' s degree
in electrical engineering, computer engineering, or computer science with coursework in digital
communications theory and 1-2 years ' experience in communications." (JCCB at 5) Defendants
disagree, but do not contend that their disagreements would make a material difference for
purposes of claim construction. (JCCB at 6 n.5) Accordingly, the Court will use Plaintiffs '
proposed definition of a POSA. 3

III.

CONSTRUCTION OF THE DISPUTED TERMS
A.

The '831 patent

U.S. Patent No. 5,602,831 , entitled "Optimizing Packet Size to Eliminate Effects of
Reception Nulls," was filed on March 31, 1995 and issued on February 11 , 1997. The patent
generally discloses methods that enable communication systems to send and receive messages
despite the presence of signal "nulls" that introduce errors into messages. (See ' 831 patent at
Abstract) The methods primarily involve reordering and interleaving data in order to reduce the
frequency ofconsecutive errors. (See id. at Figs.6 & 9, 5:66-6:56) (explaining why it is easier to

3

Defendants identify a different level of ordinary skill for each patent. (See JCCB at 6
n.5) Because the different conceptions of the POSA "do not impact" the claim construction
dispute (id.), the Court does not need to resolve this disagreement.
5

correct non-consecutive errors and showing how reordering data reduces number of consecutive
errors))
1.

"identifying changes in signal drop-out characteristics"
(' 831 patent, claim 1)

Plaintiffs' Proposed Construction

Defendants' Proposed Construction
Court's Construction

Plain and ordinary meaning or "indicator of
signal quality or loss in a communication
svstem"
'more than one characteristic of a signal dropt>ut"
'more than one characteristic of a signal dropt>ut"

Plaintiffs argue that this term should be construed according to its plain and ordinary
meaning or, alternatively, as an "indicator of signal quality or loss in a communication system."
Defendants argue that a signal drop-out characteristic is simply a characteristic of a signal dropout. The Court agrees with Defendants.
Defendants' construction is supported by intrinsic evidence. Figures 1, 3, 4, 5, and 7
explicitly equate signal drop-out characteristics with traits of a signal drop-out. (See '831 patent
at Figs.1 , 3-5, 7, and at 2:61-3:9 (explaining that figures depict signal drop-out characteristics),
1:22-29, 5:5-11 ("When the receiver is moving at 15 MPH (FIG. 3), nulls have a relatively wide
time duration and have a relatively long time period between adjacent nulls")) By contrast,
Plaintiffs' alternate construction replaces the claim language with terms that are neither
referenced nor discussed in either the patent specification or the claims.
Plaintiffs further argue that a "change" to a single trait qualifies as a change to the "signal
drop-out characteristics" as a whole (JCCB at 12), while Defendants contend that the claim term
requires a change in multiple characteristics (JCCB at 13). The Court agrees with Defendants.

6

The disputed claim term requires

"change~"

to "signal drop-out characteristic~." Both "changes"

and "characteristics" are plural. Plaintiffs ' claim differentiation argument (based on a
comparison of claims 1 and 2) does not alter this conclusion, as claim 2 (unlike claim 1) limits
the possible "signal drop-out characteristics" to "duration(s)" or "time period(s)."

2.

"encoding packets into packet blocks"
(' 831 patent, claim 1)

Plaintiffs' Proposed Construction

Defendants' Proposed Construction
~ourt's

Construction

Plain and ordinary meaning or "forming blocks
from packet data converted to compensate for
~i!!Ilal drop-out"
'forming blocks by interleaving a discrete
number of oackets together"
'forming blocks by interleaving a discrete
number of packets together"

The parties disagree about whether this claim term requires a discrete number of packets.
Defendants argue that the term requires a discrete number of packets, while Plaintiffs argue that
the claim should be construed to allow packet segmentation - a technique that would place
fractions of packets into packet blocks. The Court agrees with Defendants.
Defendants' construction is supported by the language of claim 1, which refers to
"packets" and not "packet data." Other claims (such as 10) refer to "portions of .. . packets," but
this language does not appear in claim 1. Similarly, the specification only speaks of "packets"
making up "packet blocks" and does not discuss partial packet data. Consistent with the Court's
conclusion is the PTAB ' s determination that, even under a broadest reasonable interpretation
claim construction standard, "packet blocks" mean "a block of data including a discrete number

7

of packets." (D.I. 207-17 Ex. 0 at 8) Plaintiffs' extrinsic evidence -presented to this Court but
not to the PTAB - does not change the Court' s conclusion. 4
3.

"an encoder for combining and varying the number of packets
transmitted in each of the packet blocks"
(' 831 patent, claim 9)

Plaintiffs' Prouosed Construction
Defendants' Proposed Construction

Court's Construction

Plain and ordinary meaning
'an encoder for forming blocks by interleaving 2
~iscrete number of packets together and varying
he number of packets transmitted in each of the
olocks"
'an encoder for forming blocks py interleaving a
(iiscrete number of packets together and varying
he number of packets transmitted in each of the
olocks"

The disputes relating to this term are identical to those involving the previous term. (See
JCCB at 40-41) Accordingly, the Court adopts Defendants' construction.5
B.

The '408 Patent

U.S. Patent No. 6,952,408, entitled "Method of Baseband Frequency Hopping Utilizing

4

The parties originally disagreed about whether the claim requires interleaving, but this
dispute was resolved at the hearing. (See Tr. 40-41 (explaining that Plaintiffs would support
construction that required "interleaving" as that term was articulated by patentee in IPR); see also
id. at 47-48)
5

Plaintiffs offer one argument that is unique to this term . They argue that a construction
requiring interleaving would violate the doctrine of claim differentiation by eliminating any
distinction between claims 9 and 10. See Starhome GmbH v. AT&T Mobility LLC, 743 F.3d 849,
858-59 (Fed. Cir. 2014 (describing claim differentiation)). But the presence of interleaving is not
the only difference between claims 9 and 10. Claim 10 also requires a "register for storing
packets" and requires only that "portions" of each of the packets are interleaved. (See '831
patent at 9:27-38) These differences undermine Plaintiffs' claim differentiation argument. See
Starhome, 743 F.3d at 858-59 (explaining that claim differentiation is based on presumption that
two claims will not have identical scope). Moreover, Plaintiffs' agreement that claim 1 requires
interleaving appears to extend to claim 9. (See Tr. 40-41)
8

Time Division Multiplexed Mapping Between a Radio Transceiver and Digital Signal Processing
Resources," was filed on February 20, 2001 and issued on October 4, 2005. The patent generally
discloses methods of "frequency hopping" that enable basestations to communicate more
efficiently with mobile subscribers. (See ' 408 patent at abstract)
4.

"frequency hopping"
(' 408 patent, claims 1, 2)

Plaintiffs' Proposed Construction

Preamble is not limiting.

Ifo the extent it is found to be limiting,

Defendants' Proposed Construction

C:ourt's Construction

'frequency hopping" should be construed as
'allowing mobile stations to communicate with
:Jasestations on different transmission
frequencies, the transmission frequency
changing between bursts of information" or as
'switching the frequency in a non-sequential
sequence"
lfhis preamble term limits the claim and should
be construed as "varying the frequency used at
:Jredetermined intervals using different hop
sequences that are non-correlated between
:Jasestations using a subset of the same
trequencies"
The preamble term limits the claim and means
'switching the frequency in a non-sequential
sequence"

The term "frequency hopping" appears in the preamble to claim 1 of the ' 408 patent. The
parties disagree about whether the preamble is limiting and, if so, how it should be construed. 6
The Court concludes that the preamble is limiting and adopts the construction of "frequency

6

At first, the parties disagreed only as to whether the term should be viewed as a limiting
preamble. (See JCCB at 79-82) At the hearing, however, it became clear that the parties also
disagreed as to the substantive meaning of the term. (See Tr. 89-104) The Court ordered
additional post-hearing briefing relating to this term. (See D.l. 226)
9

hopping" that was offered by Plaintiffs during an IPR of the '408 patent: "switching the
frequency in a non-sequential sequence." (See D.I. 175-35 Ex. GG at 15)
While preambles generally do not limit the scope of a patent' s claims, see Summit 6, LLC
v. Samsung Elecs. Co., 802 F.3d 1283, 1292 (Fed. Cir. 2015), a preamble can be limiting if it is

relied upon to distinguish the claimed invention from the prior art, see Catalina Mktg. Int 'l, Inc.
v. Coolsavings.com, Inc. , 289 F.3d 801 , 808 (Fed. Cir. 2002). During the IPR of the ' 408 patent,

Plaintiffs did just that. (See D.I. 175-35 Ex. GG at 3, 28 (describing frequency hopping as a "key
element of the claims" and arguing that prior art failed to "sufficiently address 'frequency
hopping"')) During the IPR, Plaintiffs also argued that "construction of ' frequency hopping' is
useful in understanding and interpreting the features recited in independent claim 1 of the '408
patent." (Id. at 16)
Furthermore, the term "frequency hopping" appears in the patent' s title and throughout
the specification. The term is needed to "give life, meaning, and vitality to the claim." Thus,
again, it is limiting. See Catalina, 289 F.3d at 808.
As it will be treated as a claim limitation, and the parties' dispute its meaning, the Court
construes "frequency hopping" as "switching the frequency in a non-sequential sequence." This
construction was offered by Plaintiffs during the IPR (D.I. 175-35 Ex. GG at 15) and is supported
by Defendants (D.I. 232 at 3). This construction is also consistent with the claim language and
the specification. (See '408 patent at 2:42-54, 11 :43-56 (describing frequency hopping)) By
contrast, Defendants' proposed construction seems to require multiple base stations and a hop
sequence that is "non-correlated" between those multiple basestations - requirements that are at
odds with the claim, which contemplates that frequency hopping can be used even if there is only

10

a single basestation. (See '408 patent at 13:18-20 ("A method for frequency hopping in a cellular
communications system .. . with a basestation ... ")(emphasis added))

5.

"a structure for allocating ones of baseband outputs from a digital
channelizer to ones of logical inputs of digital signal processors and
allocating ones of baseband inputs of a digital combiner to ones of
logical outputs of said digital signal processors according to said
mapping signal"
('408 patent, claim 2)
ot a means-plus-function limitation.

laintiffs' Proposed Construction

o the extent it is found to be a means plus
nction limitation, it has the following

unction: allocating ones of baseband outputs
om a digital channelizer to ones oflogical
nputs of digital signal processors and allocating
nes of baseband inputs of a digital combiner to
nes oflogical outputs of said digital signal
rocessors according to said mapping signal.
tructure: Bus.
eans-plus-function limitation under§ 112 if 6

efendants' Proposed Construction

unction: (1) allocating ones of baseband
utputs from a digital channelizer to ones of
ogical inputs of digital signal processors and
2) allocating ones of baseband inputs of a
igital combiner to ones oflogical outputs of
aid digital signal processors according to said
apping signal
tructure: time division multi lexed bus
eans-plus-function limitation under § 112 if 6

ourt's Construction

unction: (1) allocating ones of baseband
utputs from a digital channelizer to ones of
ogical inputs of digital signal processors and
2) allocating ones of baseband inputs of a
i ital combiner to ones oflo ·cal ou uts of
11

aid digital signal processors according to said
apping signal
tructure: time division multi lexed bus

The parties disagree about whether this claim term should be construed as a means-plusfunction limitation and, if so, what accompanying structure is disclosed in the specification. The
Court agrees with Defendants' on both disputes.
To determine whether means-plus-function claiming applies, the Court considers whether
the words of the claim would be "understood by persons of ordinary skill in the art to have a
sufficiently definite meaning as the name for structure." Williamson v. Citrix Online, LLC, 792
F.3d 1339, 1349 (Fed. Cir. 2015). When the claim term lacks the words "means," there is a
presumption that means-plus function claiming does not apply. See id. This presumption can be
overcome "if the challenger demonstrates that the claim term fails to ' recite sufficiently definite
structure. "' Id.
Defendants have shown that the claim fails to recite sufficiently definite structure. In fact,
the claim does not recite any structure. Instead, the claim merely describes the structure as "a
structure." ('408 patent at 13:30) The claim does not contain any additional details or
limitations that provide guidance as to meaning. Hence, the term "structure" amounts to a nonce
word that imparts no more meaning than words like "means," "mechanism," "element," or
"device." See Williamson, 792 F.3d at 1350 (listing words that "typically do not connote
sufficiently definite structure").
Construing a means-plus-function claim term involves two steps. "First, the court must
determine the claimed function. Second, the court must identify the corresponding structure in

12

the written description of the patent that performs that function. " Applied Med. Res. Corp. v.
US. Surgical Corp ., 448 F.3d 1324, 1332 (Fed. Cir. 2006) (internal citation omitted). While the
parties agree about the function disclosed by the present term, they disagree about the recited
structure. Plaintiffs contend that the specification discloses a generic bus. Defendants, however,
persuasively show that the corresponding structure is a "time division multiplexed bus." When
describing how the functions are performed, the specification refers exclusively to a time
division multiplex; there is no mention or discussion of any other kind of bus. (See ' 408 patent
5:25-40, 6:48-52)
In defending their proposed construction, Plaintiffs point to specification language

indicating that the time division multiplex bus "operates as a time division multiplexed cross-bar
switch." (Id. 5:34-39) Plaintiffs then argue that any bus can function as a cross-bar switch and,
thus, that the structure for this claim term includes any bus. (JCCB at 90) But means-plusfunction claims are limited to the structure disclosed in the patent specification and
corresponding to the claimed function. See Med. Instrumentation & Diagnostics Corp. v. Elekta
AB, 344 F.3d 1205, 1219 (Fed. Cir. 2003). The fact that one can identify non-disclosed

structures that can perform the disclosed function does not change this rule. The specification
does not disclose a generic bus structure.

C.

The '248 Patent

U.S . Patent No. 6,640,248, entitled "Application-Aware, Quality of Service (QoS)
Sensitive, Media Access Control (MAC) Layer," was filed on July 9, 1999 and issued on October
28, 2003. The patent discloses an application aware media access control layer that can detect

13

applications of different types and can allocate a network resource to those applications based on
application type. (See '248 patent at abstract)
6.

"allocating resources" I "allocates bandwidth resource" I "allocates
resources"
('248 patent, claims 1, 20)

Plaintiffs' Proposed Construction

0 lain

!Defendants' Proposed Construction

'[allocating I allocates] an amount of
bandwidth"
'[allocating I allocates] an amount of
bandwidth"

Court's Construction

and ordinary meaning.

The parties do not appear to have a material dispute with respect to these claim terms. At
oral argument, Plaintiffs were unable to articulate a relevant difference between the plain and
ordinary meaning of the disputed terms and Defendants ' proposed construction. (See Tr. 117 ("I
don't know whether we 're fighting over anything."))
To the extent that there is a difference between the proposed constructions, the Court will
adopt Defendants' proposal. Defendants' construction is supported by the patent specification,
which equates allocating bandwidth with allocating an amount of bandwidth. (' 248 patent at
64: 19-23 ("Different applications have different QoS requirements in order to provide an
acceptable end-user experience. For example, bandwidth allocation (i.e., allocating an
appropriate amount of bandwidth) is important to an application performing FTP file transfer
downloads . .. .");see also SkinMedica, Inc. v. Histogen Inc., 727 F.3d 1187, 1201 (Fed. Cir.
2013) (stating that "i.e." "signals an intent to define the word to which it refers").

14

7.

"application aware resource allocator at the MAC layer" I
"application-aware media access control (MAC) layer"
(' 248 patent, claims 1, 20)

laintiffs' Proposed Construction

efendants' Proposed Construction

ourt's Construction

lain and ordinary meaning, except the
reamble of claim 20 is not limiting, or " [a
esource allocator at the MAC layer/a MAC
ayer] that allocates resources based on
lication
e"
'a [resource allocator/ media access control
ayer] that has knowledge of the type of data
pplication and further takes into account, when
llocating bandwidth, information about
pplications at International Standards
rganization' s Open Systems Interworking
OSI) application layer 7"
Claim 20, this term appears in the preamble
d limits the claim, and thus should be
onstrued as set forth above.
'a [resource allocator/ media access control
ayer] that has knowledge of the type of data
pplication and further takes into account, when
llocating bandwidth, information about
pplications at International Standards
rganization' s Open Systems Interworking
OSI) application layer 7"
Claim 20, this term appears in the preamble
d limits the claim, and thus should be
onstrued as set forth above.

The parties have two disputes with respect to this claim term. First, the parties dispute
whether the resource allocator must "take into account" information about applications at OSI
application layer 7. Defendants argue that the term should be construed to require the resource
allocator to take layer 7 information into account. Plaintiffs acknowledge that the resource

15

allocator must have access to layer 7 information, but have argued that the allocator need not take
that information into account when allocating network resources.
This portion of the parties' dispute appears to have been resolved at oral argument, during
which Plaintiffs agreed with the substance of Defendants' construction. In an exchange, the
Court asked, "Do the claims require that information about applications at layer 7 be accounted
for?" (Tr. 141 ) In response, Plaintiffs answered "I think they do, Your Honor, yes. I think the
MAC layer has to account for in some fashion the information." (Id.) Accordingly, the Court
will adopt Defendants' proposed construction.7
The parties also dispute whether the preamble in which this term appears should be
construed as limiting in the context of claim 20. As explained above, a preamble can be limiting
where a patentee "reli[ ed] on the preamble during prosecution to distinguish the claimed
invention from the prior art. " Catalina , 289 F.3d at 808. Defendants have shown that the
patentee relied on the preamble during prosecution to distinguish claim 20 from the prior art.

(See JCCB at 117) In particular, during prosecution the patent applicant argued that claim 20
was patentable over the prior art " [f]or at least the reasons discussed above with reference to
independent claim l ." (D.I. 175-40 Ex. LL at 12) When distinguishing the prior art, the
applicant argued that claim 1 requires that the invention is "aware of layer 7 application
information" and that claim 1 uses information from upper level layers when allocating
resources. (Id. at 10) Because the applicant relied on the layer-7 requirement when

7

Defendants' position is also supported by the prosecution history, during which the
patentee distinguished its invention from prior art based on the fact that the invention is "aware
of layer 7 application information" and, further, that the resource allocator must "be able to take
into account, when allocating bandwidth, information at . .. layer 7." (D.I. 175-40 Ex. LL at 10;
D.I. 175-39 Ex. KK at 9)
16

distinguishing claim 20 from the prior art, the preamble should be construed as limiting.
Accordingly, the Court will adopt Defendants' proposed construction.

8.

"a module operative to recognize an application type of said software
application associated with said IP flow" I "identifying means for
identifying an application type of a software application associated
with an IP flow"
(' 248 patent, claims 17, 20)
eans-plus-function limitation under§ 112 if 6

laintiffs ' Proposed Construction

unction: to recognize an application type of
aid software application associated with said IP

unction: identifying an application type of a
oftware application associated with an IP flow
tructure: Packet header identification
omponent 1502 or 1602.
eans-plus-function limitation under§ 112 if 6

efendants' Proposed Construction

unction: to recognize an application type of
aid software application associated with said IP

tructure: None
unction: identifying an application type of a
oftware application associated with an IP flow
tructure: None
eans-plus-function limitation under§ 112 if 6

ourt' s Construction

unction: to recognize an application type of
aid software application associated with said IP

17

unction: identifying an application type of a
oftware application associated with an IP flow
tructure: Packet header identification
om anent 1502 or 1602
The parties agree that these terms should be construed as means-plus-function terms
pursuant to § 112 if 6 and agree on the functions . They disagree, however, about the
corresponding structure. Defendants contend that the patent' s specification does not disclose
sufficient structure and, consequently, that the claims are invalid as indefinite. 8 Plaintiffs argue
that packet header identification components 1502 and 1602 form the corresponding structure.
-The Court agrees with Plaintiffs.
The specification contains a detailed discussion of components 1502 and 1602, explaining
what they are and how they function. Specifically, Figures 15A and 16A provide a flow chart
indicating how the packet header components are used to identify an application type associated
with an IP flow. The specification further provides a detailed explanation of how components
1502 and 1602 recognize an application type. (Id. at 62 :41-64:43 , 68:23-38, 69:5-36) The
specification explains:
An IP flow packet stream from data network 142, including
packets from various IP flows (where each IP flow is associated

with a single data "call") is received at packet header identification

8

Throughout the briefing, Plaintiffs attempt to defend their patent claims from attacks of
indefiniteness by pointing out that one or more of the Defendants proposed constructions of the
disputed claim terms during IPR proceedings. (See, e.g., JCCB at 94 (defending ' 408 patent),
124 (defending ' 248 patent), 168 (defending ' 994 patent), 222 (defending ' 431 patent)) The
Court is unpersuaded by this argument. The PTAB does not consider whether a claim is
indefinite. See 35 U .S.C. § 311 (b ). The fact that Defendants proposed constructions in order to
facilitate IPR challenges on grounds of obviousness and anticipation is not a concession that a
POSA would arrive at those constructions with "reasonable certainty."
18

component 1502 .... For IP flows known to the system, so-called
"existing IP flows ," there are entries in a table 1526. An IP flow is
in the system if there is an existing characterized IP data call. In
module 1522, it is determined if there is a match between the
incoming packet and an existing IP flow call in an entry in existing
IP flow identification table 1526. If so, then the IP flow is known
to the system, and control passes to module 1530 of the packet
characterization component 1504.

If not, meaning that the IP flow is a new IP data flow, then
control passes to module 1524, where the packet header fields are
analyzed. Module 1524 analyzes the packet header source field
and determines from source application packet header data table
1528 the type of source application making the data call or
transmitting the IP packet. . . . If the IP flow is not known to the
system, then the IP flow is given an IP flow identifier number, and
control passes to module 1526 where the IP flow identifier number
is added to the existing IP flow identification table 1526.
(' 248 patent at 63: 14-54) This is adequate corresponding structure for both of the claimed
functions.
Accordingly, the Court will adopt Plaintiffs' proposed construction.

9.

"allocating means for allocating resources to said IP flow ... so as to
optimize end user application IP QoS requirements of said software
application"
(' 248 patent, claim 20)
eans-plus-function limitation under§ 112 i! 6

laintiffs' Proposed Construction

unction: allocating resources to said IP flow
.. so as to optimize end user application IP Qo
equirements of said software application
tructure: MAC downlink subframe scheduler
odule 1566 or MAC uplink subframe
cheduler 1666.
o the extent necess
19

Oefendants' Proposed Construction

'assigning future slots to data packets based on
the priority of the IP data flow with which the
backet is associated"
Means-plus-function limitation under§ 112 ii 6
Function: Indefinite/ allocating resources to
said IP flow ... so as to optimize end user
application IP QoS requirements of said
software application

Court's Construction

Structure: None
Means-plus-function limitation under§ 112 ii 6
Function: Indefinite
Structure: The Court does not reach this issue

While the parties agree that this term should be construed as a means-plus-function term
pursuant to § 112 ii 6, they disagree about the scope of the claimed function and about the
sufficiency of the structure disclosed in the specification. Defendants argue that the term
"optimize," as used in the claimed function, is indefinite, since the specification does not provide
any objective boundaries that would allow a POSA to know whether a given system is optimized.
The Court agrees.
In Nautilus, Inc. v. Biosig Instruments, Inc., 134 S. Ct. 2120, 2124 (2014), the Supreme
Court held that a patent "is invalid for indefiniteness if its claims, read in light of the
specification ... fails to inform, with reasonable certainty, those skilled in the art about the scope
of the invention." " [A] term of degree fails to provide sufficient notice of its scope ifit depends
on the unpredictable vagaries of any one person' s opinion." Interval Licensing LLC v. AOL, Inc.,
766 F.3d 1364, 1371 (Fed. Cir. 2014) (citing Nautilus, 134 S. Ct. at 2130).

20

In explaining what it means to "optimize" end user QoS, the specification indicates that
QoS is subjective and that QoS can vary from user to user based on individual preferences. (See
'248 patent at 13:20-27 (explaining that system seeks to "provide[) user[s] with optimal service,
in whatever manner the user defines it"); see also id. at 12:62-65 (explaining that QoS is
continuum that is "defined by what network performance characteristic is most important to a
particular user")) This subjective, user-based understanding would make it difficult, if not
impossible for a POSA to ascertain, with reasonable certainty, whether the claim limitation is
satisfied by any particular embodiment. As Defendants' expert opined, the specification
"provides no objective boundaries" and leaves the standard for measuring optimization
"completely unbounded. " (D.I. 210-6 Ex. A5

~~

78-81 )

In response to these arguments, Plaintiffs identify portions of the specification that
"provide[) specific examples of which QoS criteria are the 'best measure ' of end-user QoS for
particular applications." (JCCB at 144 (citing ' 248 patent at 2:54-62, 14:43-50)) The cited
portions of the specification, however, do not provide adequate guidance as to the meaning of
"optimize," nor do they rectify the indefiniteness of the portions of the specification indicating
that QoS is subjective and varies by user. Based on the intrinsic and extrinsic evidence, the
Court is persuaded, by clear and convincing evidence, that the term "optimize," as it is used in
the ' 248 patent is indefinite. 9
Because the Court concludes that the recited function for this term is indefinite, the Court
does not reach the disputes relating to the adequacy of the recited structure and algorithm.

9

This conclusion is consistent with previous decisions relating to similar terms. See, e.g. ,
Netgear, Inc. v. Ruckus Wireless, Inc., 5 F. Supp. 3d 592, 610 (D. Del. 2013) (concluding that
term "optimal conditions" was indefinite).
21

D.

The '994 Patent

U.S. Patent No. 7,385,994, entitled "Packet Data Queuing and Processing," was filed on
October 23 , 2002 and issued on June 10, 2008 . The patent generally relates to methods and
means for allocating a limited bandwidth resource to many users in a shared network setting.
The invention involves four structures : data, data packets, data packet queues, and data
packet queue tiers. Data refers to information that users want to send over a network. In order to
be sent, the data must be organized into data packets. (' 994 patent at 1:67-2:4 ("In packetswitched data networks, information or messages are divided into ... data packets for
transmission.")) These data packets are placed into data packet queues, which are used to
determine the order in which data packets will be sent. (Id. at 2:52-57 ("Hence, a number of data
packets are ' queued ' until the gateway transfers the data packet . ... The gateway includes a
gateway queue algorithm that determines how [bandwidth] is to be shared between queued data
packets from the respective clients."))
The network systems implicated by the ' 994 patent typically have several data packet
queues that share the same bandwidth resource. (See id. at 2:67-3:1 ) The invention shares the
bandwidth across different queues by assigning each queue to a tier. Each tier is assigned a
weight that is used to determine what proportion of bandwidth resources will be allocated to each
tier. (See id. at 4: 13-29)

22

10.

"allocating a proportion of said total number of data packets to a
number of the tiers of service to allow individual packet data queues
on a number of tiers to share a communication resource"
('994 patent, claims 1, 11)

Plaintiffs' Construction

Plain and ordinary meaning

Defendants' Construction

"allocating a known fraction of said total
number of data packets to each of a number
of tiers of service to share a communication
resource among individual data packet queues
on a number of tiers"

Court's Construction

Plain and ordinary meaning

Plaintiffs argue that the Court need only say that the plain and ordinary meaning applies to
this term. Defendants, by contrast, seek to modify the claim term in several ways. First,
Defendants ask the Court to construe "proportion" as "a known fraction. " The Court agrees with
Plaintiffs that this improperly reads in a limitation from an embodiment in the specification and
confusingly raises the issue of "known to whom?" Second, Defendants ask the Court to read the
claim language "a number of the tiers" to mean "each of a number of tiers." But nothing in the
specification requires that each tier receives an allocation. In fact, the specification contemplates
that at least some tiers will be left out. (See ' 994 patent at 4:44-47 (explaining that method
"provid[es] [a] communication resource to queued packet data users ... such that [the]
communication resource is made available to a substantial number of tiers") (emphasis added))
Moreover, the patentee used the word "each" elsewhere in the claims impacted by this dispute,
and in other claims. (See, e.g., '994 patent at 7:23 , 9:19, 10:23) It follows that the patent' s use
of "a number" rather than "each" was intentional, thereby cautioning against reading "each" into
the claim where it does not appear. See Philips, 415 F.3d at 1314. Finally, Defendants'

23

construction would rearrange certain words in the claim and replace certain words with others.
The parties have not shown they have any material dispute with respect to this portion of
Defendants ' proposal, which is a reason for the Court to refrain from adopting it. In sum, as
Defendants ' proposed construction is unsupported by the intrinsic evidence and might be
confusing to the jury, the Court adopts Plaintiffs ' position.

11.

"means for allocating a tier of service for each of a plurality of
individual packet data queues, wherein the means for allocating
allocates different weights to each tier of service based on a number of
users requiring access to the available communication resource"
(' 994 patent, claim 11 )

Plaintiffs' Proposed Construction

Means-plus-function limitation under§ 112
ii 6

Function: allocating a tier of service for each
of a plurality of individual packet data
queues, wherein the means for allocating
allocates different weights to each tier of
service based on a number of users requiring
access to the available communication
resource
Structure: RNC236-240 and/or Logic 248250 implementing algorithm:
<f>tier_i = (Ntier_i *Stier)/(~= l toL: Ntier_k*Stier_k)
Means-plus-function limitation under§ 112 ii
6

Defendants' Proposed Construction

Function: allocating a tier of service for each
of a plurality of individual packet data
queues, wherein the means for allocating
allocates different weights to each tier of
service based on a number of users requiring
access to the available communication
resource
Structure: None
24

Means-plus-function limitation under§ 112

Court's Construction

ii 6
Function: allocating a tier of service for each
of a plurality of individual packet data
queues, wherein the means for allocating
allocates different weights to each tier of
service based on a number of users requiring
access to the available communication
resource
Structure: RNC236-240 and/or Logic 248250 implementing algorithm:
<fltier i = (Ntier i*Stier )/(Lk 10 L: Ntier k*Stier k)
=J
The parties agree that this term should be construed as a means-plus-function term, and
agree on the function, but they disagree about the disclosed structure. Plaintiffs argue that the
specification discloses an algorithm (<f>tier_i = CNcier_i*S tier)/(~= I 10 L: Ntier_k*Stier_k)) to implement the
stated function. Defendants argue that the algorithm identified by Plaintiffs is not sufficiently
linked to the stated function and that no other algorithm is disclosed. The Court agrees with
Plaintiffs.
The specification teaches that "weights" are used to control or determine the "relative
proportions of system bandwidth allocated to each tier." (' 994 patent at 6:59-63) The
specification further explains that "weight" can be denoted with a " <p" symbol. (See id. at 3 :6-7
(explaining that one can define "parameters <p 1 ... <pN (weights) that set the number of bits
allocated to each user per round")) Hence, the equation identified by Plaintiffs performs the
function described by the claim term: it assigns a weight (a <p value) to each tier based on the
number of users operating at that tier (N ) and in the system as a whole.
Defendants argue that Plaintiffs' equation is not clearly linked to the stated function. (Tr.

25

165 ("[T] he specification does not clearly link IV ' s identified <raer_i formula to the different
weight function. "); D.I. 209 at 4-5) Defendants' argument is based on the patent's somewhat
inconsistent use of the terms "weight" and "proportion." At one point, the patent associates "cp"
with weight (' 994 patent at 3:6-7), while at another point it describes "cp" as a "proportion" (id.
at 7:34-44 ("Thus, the proportion of the entire system resource, allocated to the 1th tier .. . can be
defined by [Plaintiffs' equation].")) While these criticisms seem to show that the patent is not a
model of drafting perfection, they do not, in the Court' s view, amount to reason to disregard the
specification' s language clearly associating "cp" with tier weight.
As the Court has found that "cp" can be used to define tier weights, it follows that
Plaintiffs' equation provides sufficient structure. A person of ordinary skill in the art would
recognize that Plaintiffs' equation is the only structure in the specification that performs the
identified function - no other equation assigns weight-values based on the number of users
attempting to access a bandwidth resource. (See also PMX 24 iii! 36-38 (expert report indicating
that Plaintiffs ' equation is based on number of users))

12.

"means for determining a total number of data packets that can use
an available communication resource"
(' 994 patent, claim 11 )

Plaintiffs' Proposed Construction

Means-plus-function limitation under § 112 iJ 6

Function: determining a total number of data
packets that can use an available communicatior
esource
Structure: RNC236-240 and/or Logic 248-250
using the method disclosed at 6:29-37.
Defendants' Proposed Construction

Means-plus-function limitation under§ 112 iJ 6

26

unction: determining a total number of data
ackets that can use an available communicatio

tructure: None
eans-plus-function limitation under§ 112 if 6

ourt's Construction

unction: determining a total number of data
ackets that can use an available communicatio

tructure: RNC236-240 and/or Logic 248-250
sing the method disclosed at 6:29-37.
pecifically, the total number of data packets is
qual to the bandwidth speed*round
uration/packet size. This structure, and thus
he claim, only applies where data packets are o
fixed size.
The parties agree that this term should be construed as a means-plus-function term
pursuant to § 112 if 6, and agree on the function, but once again disagree as to the corresponding
structure. Plaintiffs argue that the specification discloses an algorithm that can be used to
calculate the number of data packets: bandwidth speed*round duration/packet size. (See ' 994
patent at6:29-37 (providing example)) Defendants respond that the specification does not
provide sufficient structure and the limited structure contained in the specification applies only
when data packets are of the same size.
In the Court' s view, the specification contains sufficient detail to satisfy the structural

requirements of the means-plus-function claim term. An algorithm need not be presented in any
particular form in order to provide sufficient corresponding structure. So long as the
specification provides sufficient detail, the algorithm may be expressed "in any understandable
terms including as a mathematical formula, in prose, or as a flow chart, or in any other manner
27

that provides sufficient structure." See Noah Systems, Inc., 675 F.3d 1302, 1312 (Fed. Cir.
2012).
The '994 patent uses an illustrative example to describe how to determine the number of
packets that can be sent during a period. (See ' 994 patent at 6:29-37) The specification states:
"[I]fusers compete for a 10 Mbps link, the users transmit data packets oflength 1 kbit and ...
the round period is 10 msec ... [then] in each round 100 packets are allocated." That is, the
number of packets that can be sent is equal to the total number of bits that can be transferred
divided by the number of bits in a packet. (See D.I. 211-1 Ex. A8 (Rubin 2nd Supp. Deel.) if 28
(describing equation)) 10
While the algorithm provided in the specification works for systems with a fixed packet
length, it cannot be used to determine how many packets can be sent in an environment with a
variable packet length. (See id. iii! 29-31 ) Because means-plus-function claims are limited to the
structure disclosed in the specification, see Med. Instrumentation & Diagnostics Corp. , 344 F.3d
at 1219, the scope of the disputed claim term must be limited to systems having a fixed packet
length.
It is true that the specification states that "the inventive concepts could still be applied
when non-fixed length packets are employed." (Id. at 6:38-41 ; Tr. 155 (suggesting that one
could use same equation in variable-packet-size environment by using average, minimum, or
maximum, packet size)) While this statement arguably hints at an algorithm that could be

10

This is consistent with the patent' s example. When one converts the units involved in
the example, the problem involves a link that can send 10,000,000 bits per second, with data
packets having a length of 1,000, and a period lasting .01 seconds. This yields an equation of
10,000,000* .0111 ,000=100,000/1 ,000=100.
28

provided to allow the invention to work with non-fixed length packets, it is not the algorithm
itself, and the algorithm to do so does not appear in the patent.
13.

"scheduling means to provide said communication resource to queued
packet data users on a tier-by-tier basis, such that said resource is
made available to all tiers"
(' 994 patent, claim 11 )

eans-plus-function limitation under§ 112 ii 6

laintiffs' Proposed Construction

unction: provide said communication resourc
o queued packet data users on a tier-by-tier
asis, such that said resource is made available
o all tiers
tructure: RNC236-240 and/or Logic 248-250
dapted to facilitate packet queuing and
cheduling in a round-robin fashion as disclosed
n the patent at 7:53-8 :14

eans-plus-function limitation under§ 112 ii 6

efendants' Proposed Construction

unction: provide said communication resourc
o queued packet data users on a tier-by-tier
asis, such that said resource is made available
o all tiers
tructure: None
eans-plus-function limitation under§ 112 ii 6

ourt's Construction

unction: provide said communication resourc
o queued packet data users on a tier-by-tier
asis, such that said resource is made available
o all tiers
tructure: RNC236-240 and/or Logic 248-250
dapted to facilitate packet queuing and
cheduling in a round-robin fashion as disclosed
n the atent at 7:53-8:14

29

The parties agree that this term should be construed as a means-plus-function term
pursuant to § 112 if 6, and agree as to the function, but disagree about the disclosed structure.
Defendants argue that the specification does not disclose an algorithm that performs the
identified function. Plaintiffs disagree. The Court sides with Plaintiffs.
The specification provides a detailed explanation of how the communication resource is
distributed to each user and to all tiers. (See ' 994 patent at 7:53-8 :14) Specifically, the patent
explains that ei packets are allocated to each tier in succession and that, within each tier, the 8
packets are distributed in a round-robin fashion. (See id.) This is a sufficient algorithm.

14.

"means ... for allocating a proportion of said total number of data
packets to a number of the tiers of service to allow individual packet
data queues on a number of tiers to share a communication resource"
(' 994 patent, claim 11 )
eans-plus-function limitation under§ 112 if 6

laintiffs' Proposed Construction

unction: allocating a proportion of said total
umber of data packets to a number of the tiers
f service to allow individual packet data queue
n a number of tiers to share a communication

efendants' Proposed Construction

tructure: RNC236-240 and/or Logic 248-250
m lementin the al orithm e =
eans-plus-function limitation under§ 112 if 6
unction: allocating a proportion of said total
umber of data packets to a number of the tiers
f service to allow individual packet data queue
n a number of tiers to share a communication

tructure: None
eans-plus-function limitation under§ 112 if 6

ourt's Construction

30

umber of data packets to a number of the tiers
f service to allow individual packet data queue
n a number of tiers to share a communication

Once again, the parties agree that this term should be construed as a means-plus-function
term pursuant to § 112 ii 6, and agree on the function, but disagree about the corresponding
structure. Plaintiffs argue that the specification discloses an algorithm that can be used to
allocate a proportion of data packets to a number of tiers of service. (See ' 994 patent at 7:47-51
(explaining that number of packets allocated to each tier is 8, = <P,.,,. -*~ )) Defendants argue that
Plaintiffs ' proposed structure is inadequate because it is not sufficiently linked to the agreedupon function. Specifically, Defendants argue that Plaintiffs ' proposed algorithm is insufficient
because it relates to a number of data packets, rather than a proportion of data packets. (Tr. 176
(arguing that 8, "defines the actual number of packets that can be allocated to a tier . . . not a
proportion .. .. "); D.I. 211at8-9)
The Court agrees with Plaintiffs. The number of data packets allocated to each tier (8,) is
equal to a proportion (cp h of the total number of data packets. (See ' 994 patent at 7 :44-51 ) This
)
means that allocating 8, packets necessarily allocates a proportion of the total number of data
packets to tier i. (See '994 patent at 8:1-2 (explaining that packets are distributed "in the preallocated proportions for each tier"))
Therefore, the specification discloses sufficient corresponding structure and the Court will
adopt Plaintiffs' proposed construction.

31

E.

The '431 Patent

U.S. Patent No. 7,787,431 , entitled "Methods and Apparatus for Multi-Carrier
Communications with Variable Channel Bandwidth," was filed on April 29, 2005 and issued on
August 31, 2010. The patent generally discloses methods that enable multi-carrier
communication with variable channel bandwidth. (' 431 patent at abstract)
15.

"primary preamble sufficient to enable radio operations"
('431 patent, claims 8, 18)

Plaintiffs' Proposed Construction
Defendants' Proposed Construction

Court's Construction

Plain and ordinarv meaning.
'information at the beginning of a transmission
hat alone enables data channels and control
channels in the coreband to be received and
processed"
IA..ltemativelv, this claim term is indefinite.
~ 'information at the beginning of a transmission
hat alone enables radio operations"

The parties have three disputes relating to this claim term. Defendants contend that the
primary preamble must be located at the beginning of a transmission, that the preamble "alone"
should be able to enable radio operations, and that "radio operations" should be limited to
receiving and processing data channels and control channels. Plaintiffs disagree on each of these
issues and argue that the claim term should be construed according to its plain and ordinary
meaning. The Court agrees with Defendants with respect to the first two issues, but agrees with

32

Plaintiffs on the third. 11 Alternatively, Defendants contend the term is indefinite, but they have
failed to prove this contention.
First, the Court concludes that the primary preamble must be located at the beginning of a
transmission. This conclusion is supported by the plain and ordinary meaning of "preamble" and
by the specification. The plain and ordinary meaning of a "preamble,' in the context of the
pertinent art, is an introductory or preliminary statement. Indeed, Plaintiffs acknowledge that, "in
common parlance, a 'preamble' is something that precedes something else." (JCCB at 201 )
Consistent with this plain and ordinary meaning, the specification states that "[t]he downlink
transmission in each frame begins with a downlink preamble" and that "uplink transmission[ s]
can begin with an uplink preamble." (' 431 patent at 3:51-52, 56-60 (explaining that uplink
preamble is used for "initial ranging during power up")) Although unnecessary to consider,
Defendants' construction of "preamble" is further supported by extrinsic evidence. (See D.I.
210-2 Ex. A2 (engineering dictionary defining preamble as "a sequence of bits at the start of each
new transmission. "))
The Court also agrees with Defendants that the primary preamble must be sufficient, in
and of itself, to enable radio operations. The plain and ordinary meaning of "sufficient," as
understood in this art, supports this conclusion. If something is "sufficient" to perform a task,
then that something is adequate, in and of itself, to perform the task. It thus follows that the

11

With respect to this claim term, the PTAB stated: "We determine that, in the context of
the '431 patent, ' a primary preamble sufficient for basic radio operation' means a primary
preamble sufficient for a mobile station to operate in its primary state .. " (See D.I. 210-33
PMX25 at 13)
33

primary preamble alone must be able to enable basic radio operations. This construction is
supported by at least one embodiment in the specification. (See '431 patent at 5:19-22)
On the third dispute, the Court agrees with Plaintiffs that "radio operations" should be
construed according to its plain and ordinary meaning. Defendants would have the Court
construe "radio operations" as "receiving and processing data channels and control channels."
Defendants' position is based on a statement in the specification that "a set of data channels and
their related dedicated control channels are placed within the [core band] to maintain basic radio
operation." (Id. at 5:8-18) (emphasis added) But "maintaining" basic radio operation is not the
same thing as "enabling" radio operation (the latter being part of the term being construed).
Also, the portion of the specification on which Defendants rely relates to "basic radio operation,"
while the claim term in dispute references "radio operations," which may be a broader term.
Where claims use different terms to identify similar claim limitations, there is a presumption that
those different terms have different meanings. See Bancorp Servs. , L.L. C v. Hartford Life Ins.

Co. , 359 F.3d 1367, 1373 (Fed. Cir. 2004). All of this leaves the Court unpersuaded that it
should adopt the last part of Defendants' proposed construction.
16.

"an autocorrelation having a large correlation peak with respect to
sidelobes; a cross-correlation with other primary preambles having a
small cross-correlation coefficient with respect to power of other
primary preambles; and a small peak-to-average ratio; and wherein a
large number of primary preamble sequences exhibit the properties"
(' 4 31 patent, claims 8, 18)

!Plaintiffs' Prooosed Construction
Defendants' Prooosed Construction
~ourt's Construction

l>lain and ordinarv meanin12:.
[ndefinite
llndefinite

34

The claim language in dispute here uses terms of degree : "large" two times and "small"
two times. Defendants argue that each of these terms is indefinite because, in the context of the
claims here, a POSA would not understand the terms "large" and "small" with "reasonable
certainty." See Nautilus, Inc., 134 S. Ct. at 2124.
The Court agrees with Defendants. The claim limitation "a large number of primary
preamble sequences exhibit the properties" is illustrative. Nothing in the claim language,
specification, or prosecution history provides any guidance as to the meaning of the phrase "a
large number." (See '431 patent at 5:35-36, 49-50 (indicating only that number of primary
preamble sequences must be "relatively large")) Turning to the extrinsic evidence, see Teva , 135
S. Ct. at 841, Defendants' expert, Jeffrey Fischer, opined that a POSA would not understand
what constitutes a "large number." (D.I. 210-4 Ex. A4 iii! 65-69) Fischer explained that "the
patent does not provide any guidance that would allow one of ordinary skill in the art to
determine with reasonable certainty when a count of sequences becomes 'large.'" (Id.

if 65)

Fischer also opined that the specification' s use of the phrase "relatively large" increases
uncertainty by "impl[ying] that the number of sequences should be compared to something else,
without explaining what that is." (Id.

if 68) The Court finds Fischer' s analysis persuasive.

By contrast, Plaintiffs' expert' s declaration is conclusory and fails to explain how a POSA
would be able to distinguish between large numbers and almost-large numbers. (See PMX 12

35

if 18) The PTO Examiner statements on which Plaintiffs rely are also generally unpersuasive,
both because the Examiner did not expressly address the terms and because the patent was
prosecuted under the less exacting, pre-Nautilus standard for indefiniteness. 12
Overall, the totality of evidence, intrinsic and extrinsic, clearly and convincingly
demonstrates that the claim terms listed here, all of which include "large" or "small," are invalid
as indefinite.
17.

"wherein the core-band is substantially centered at an operating
center frequency"
('431 patent, claims 8, 18)

lain and ordina
definite
lain and ordina

ourt's Construction

Defendants have failed to present clear and convincing evidence that the term
"substantially centered" is indefinite. Defendants argue there is a lack of guidance in the claim
language and in the patent specification. (JCCB at 230-31) However, the prosecution history
supports Plaintiffs, as it shows the Examiner viewed this claim language as "balanc[ing] clarity
with the fact that real-world systems have process and operational tolerances whereby a coreband may not be exactly centered .. . despite efforts to center the core band." (D.I. 207-46 Ex.
RR at IV-DEL 6279) Based on this reasoning, the Examiner expressly concluded that "one of
ordinary skill in the relevant art would understand [the patent' s] use of 'substantially."' (Id. )

12

In any case, the question of indefiniteness needs to be decided by the Court, even though
any issued patent will, by definition, not have been found indefinite by the PTO.

36

Defendants have not persuaded the Court to reach a different conclusion. 13

III.

CONCLUSION
An appropriate Order follows.

13

Defendants correctly note that the patent was prosecuted prior to the Nautilus decision.
Still, with respect to this term, the Court agrees with the Examiner's express conclusion that a
POSA "would understand" the term.
37