Court Opinion

ID: 3207855
Source: CourtListenerOpinion
Date Created: 2016-05-31 15:01:13.124289+00
Date Added: 2024-06-11T14:29:05.610160
License: Public Domain

United States Court of Appeals
      for the Federal Circuit
                 ______________________

RUCKUS WIRELESS, INC., CISCO SYSTEMS, INC.,
            Plaintiffs-Appellees

                            v.

    INNOVATIVE WIRELESS SOLUTIONS, LLC,
              Defendant-Appellant
             ______________________

                  2015-1425, 2015-1438
                 ______________________

    Appeals from the United States District Court for the
Western District of Texas in Nos. 1:13-cv-00492-LY, 1:13-
cv-00504-LY, Judge Lee Yeakel.
                 ______________________

                 Decided: May 31, 2016
                 ______________________

   MATTHEW YUNGWIRTH, Duane Morris LLP, Atlanta,
GA, argued for plaintiffs-appellees. Also represented by L.
NORWOOD JAMESON; DIANA SANGALLI, Houston, TX.

    JONATHAN DANIEL BAKER, Farney Daniels PC, San
Mateo, CA, argued for defendant-appellant. Also repre-
sented by MICHAEL D. SAUNDERS, Georgetown, TX.
               ______________________
2    RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS

      Before PROST, Chief Judge, REYNA, Circuit Judge, and
                STARK, Chief District Judge. 1
     Opinion for the court filed by Circuit Judge REYNA.
    Dissenting opinion filed by Chief District Judge STARK.
REYNA, Circuit Judge.
    Innovative Wireless Solutions (“IWS”) appeals the fi-
nal judgment of non-infringement of the district court in
the Western District of Texas. IWS challenges the district
court’s conclusion that the asserted patent claims are
limited to wired rather than wireless communications.
Because we find no error in the district court’s construc-
tion, we affirm.
                        BACKGROUND
    IWS owns U.S. Patent Nos. 5,912,895; 6,327,264; and
6,587,473 (“Terry patents”). The patents are a line of
continuations beginning with the ’895 patent. All share
the ’895 specification.
    In April 2013, IWS commenced a litigation campaign
against several dozen hotels and coffee shops doing busi-
ness in the Eastern District of Texas. IWS alleged that
each defendant infringed the Terry patents by providing
WiFi Internet access to its customers using off-the-shelf
WiFi equipment sold by Ruckus and Cisco (“Ruckus”).
Ruckus responded by filing for declaratory judgment of
invalidity and non-infringement in the Western District of
Texas. On the issue of non-infringement, Ruckus argued
that its wireless equipment does not infringe the Terry
patents because the Terry patents are limited to wired
rather than wireless communications.

      1The Honorable Leonard P. Stark, Chief District
Judge, United States District Court for the District of
Delaware, sitting by designation.
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   3

     The Terry patents concern techniques for providing
access to a local area network (LAN) from a relatively
distant computer. ’895 patent col. 3 ll. 13–31. A LAN is a
group of computers connected by a shared short-range
transmission medium and configured to communicate
using a given LAN protocol. Id. col. 1 ll. 13–31. When
two computers on the LAN transmit onto the medium
concurrently, they create interference known as a “colli-
sion,” and the concurrent communications may be lost.
Id. col. 3 ll. 47–53. To deal with these collisions, a LAN
protocol may define a contention scheme. Id. col. 8 ll. 4–
25. For instance, in a “collision detection” scheme, a
transmitting computer that detects a collision waits for a
given period before reattempting the transmission. Id.
col. 7 ll. 66–67, col. 8 ll. 1–18. “Carrier Sense Multiple
Access with Collision Detection” (CSMA/CD) is an IEEE
standard LAN protocol that uses collision detection. Id.;
id. col. 1 ll. 25-33.
     The further apart two devices are on a LAN, the long-
er it takes transmissions between those devices to trav-
erse the transmission medium. Id. col. 1 ll. 61–67, col. 2
ll. 1–18. When the devices are sufficiently far apart, the
long transmission delays may render collision detection
ineffective. Id. col. 8 ll. 26–43. Consequently, it is not
practical to use LAN protocols with collision detection
over long distances, such as those spanned by telephone
lines. Id.
     The Terry patents describe an approach by which a
computer may communicate with a LAN over the long
distances covered by telephone lines. The inventors
propose using a collision avoidance scheme rather than a
collision detection scheme. Id. col. 9 ll. 32–51. Under the
avoidance scheme, a “master” modem in the LAN dictates
the timing of one-way communications between the
master modem and a “slave” modem in the distant com-
puter. Id. Although the patents only describe connecting
the master and slave modems over physical wires, such as
4   RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS

a telephone line, the claims recite that the two modems
are connected via a “communications path.” Claim 1 of
the ’895 patent is representative:
    1. A method of providing communications with a
       CSMA/CD (Carrier Sense Multiple Access with
       Collision Detection) network via a bidirectional
       communications path, comprising the steps of:
    at a first end of the communications path, provid-
       ing a CSMA/CD interface to the network, buff-
       ering information packets received from the
       network via the interface in a first buffer, sup-
       plying information packets from the first buffer
       to the communications path, and supplying
       control information to the communications
       path;
    at a second end of the communications path, buff-
       ering information packets received via the
       communications path in a second buffer, receiv-
       ing the control information from the communi-
       cations path, buffering information packets to
       be supplied via the communications path to the
       network in a third buffer, and supplying infor-
       mation packets from the third buffer to the
       communications path in dependence upon the
       control information; and
    at the first end of the communications path, sup-
       plying information packets received via the
       communications path to a fourth buffer, and
       supplying the information packets from the
       fourth buffer to the network via the interface;
    wherein the control information and the depend-
      ence on the control information for supplying
      information packets from the third buffer to the
      communications path are arranged to avoid col-
      lisions on the communications path between in-
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   5

      formation packets communicated from the first
      buffer to the second buffer and information
      packets communicated from the third buffer to
      the fourth buffer.
Id. col. 21 ll. 5–37 (claim 1). The Terry patents make no
mention of wireless communication.
    The central dispute during claim construction was
whether the recited “communications path” captures
wireless communications or is limited to wired communi-
cation. The district court adopted the latter view by
construing “communications path” to mean “communica-
tions path utilizing twisted-pair wiring that is too long to
permit conventional 10BASE-T or similar LAN (Local
Area Network) interconnections.” Cisco Sys., Inc. v.
Innovative Wireless Sols., LLC, No. 1:13-CV-00492-LY,
2015 WL 128138, at *8 (W.D. Tex. Jan. 8, 2015). The
district court reasoned that the specification’s “repeated
reference to two-wire lines and telephone lines emphasiz-
es that the inventor was focused on this transmission
medium as the core of the new technology,” and it there-
fore concluded that, in view of the entire specification,
“the Terry Patents are solely focused on communicating
information packets long distances over wired communi-
cation paths.” Id. at *7. The district court found particu-
larly persuasive a passage from the written description
regarding the scope of alternative embodiments. That
passage states that, “although as described here the line
12 is a telephone subscriber line, it can be appreciated
that the same arrangement of master and slave modems
operating in accordance with the new protocol can be used
to communicate Ethernet frames via any twisted pair
wiring which is too long to permit conventional 10BASE-T
or similar LAN interconnections.” Id. The district court
considered this passage evidence that the inventors
contemplated different types of communication paths but
chose to limit those types to “any twisted-pair wiring that
6   RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS

is too long to permit conventional LAN interconnections.”
Id. at 8.
    Based on the district court’s construction, the parties
stipulated jointly to a final judgment of non-infringement.
IWS appeals the construction limiting the term “commu-
nications path” to wired communication.
                       DISCUSSION
    Where the district court’s claim construction relies on-
ly on intrinsic evidence, the construction is a legal deter-
mination reviewed de novo. Teva Pharm. USA, Inc. v.
Sandoz, Inc., 135 S. Ct. 831, 841 (2015). Although the
district court here heard a technology tutorial with expert
testimony, it relied only on intrinsic evidence to construe
the term “communications path.” We therefore review
that construction de novo.
    “[T]he words of a claim are generally given their ordi-
nary and customary meaning,” which 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.” Phillips
v. AWH Corp., 415 F.3d 1303, 1312–13 (Fed. Cir. 2005)
(en banc) (quoting Vitronics Corp. v. Conceptronic, Inc., 90
F.3d 1576, 1582 (Fed. Cir. 1996)). The ordinary meaning
may be determined by reviewing various sources, such as
the claims themselves, the specification, the prosecution
history, dictionaries, and any other relevant evidence.
See Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313,
1325 (Fed. Cir. 2002). Ultimately, “[t]he only meaning
that matters in claim construction is the meaning in the
context of the patent.” Trs. of Columbia Univ. v. Syman-
tec Corp., 811 F.3d 1359, 1363 (Fed. Cir. 2016). Legal
error arises when a court relies on extrinsic evidence that
contradicts the intrinsic record. See Lighting Ballast
Control LLC v. Philips Elecs. N. Am. Corp., 790 F.3d
1329, 1338 (Fed. Cir. 2015); On-Line Techs., Inc. v. Bo-
denseewerk Perkin-Elmer GmbH, 386 F.3d 1133, 1138–39
(Fed. Cir. 2004).
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   7

    IWS argues that the district court erred by importing
the wired limitation into the claims. IWS argues it is
improper to read a limitation into the claims on the basis
that every disclosed embodiment includes that limitation.
Finally, it argues that because several dependent claims
limit the communications path to “two-wire line” or “two-
wire telephone line,” the unmodified “communications
path” term must encompass more, including wireless
communications.
    Ruckus counters the term “communications path”
does not have a plain and ordinary meaning to a person
having ordinary skill in the art. Ruckus also argues that
the wired limitation was proper because that limitation is
a “core feature” of the invention, which is a solution to a
problem arising in long-distance communication over
wires. It echoes the district court’s reasoning that the
specification limits the scope of the invention to “any
twisted pair wiring which is too long to permit conven-
tional . . . LAN interconnections.” It dismisses IWS’s
claim differentiation arguments because “two-wire tele-
phone line” is only one type of several wired lines dis-
closed in the specification, meaning that the term
“communications path” need not cover wireless communi-
cations to be broader than “two-wire telephone line.”
    IWS’s argument relies on the assumption that “com-
munications path” has an ordinary meaning which en-
compasses both wired and wireless communications. But
we see no intrinsic or extrinsic evidence to support IWS’s
assumption that a person of ordinary skill at the time of
invention would have understood the plain and ordinary
meaning of “communications path” to include wireless
communications. We see nothing in the intrinsic record
that would have suggested to one of ordinary skill that
“communications path” refers to wireless communications.
To the contrary, the intrinsic record militates powerfully
against that understanding. First, the title of the Terry
patents indicates that they are directed to “Communi-
8   RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS

cating Information Packets Via Telephone Lines.” ’895
patent col. 1 ll. 1–4 (emphasis added). 2 Second, the
specification describes “[t]his invention” as one “particu-
larly concerned” with “two wire lines such as telephone
subscriber lines.” Id. col. 1 ll. 6–10. Third, every embod-
iment described in the specification utilizes a telephone
wire, and when the specification clarifies that the full
breadth of the invention is not limited to the expressed
embodiments, it declares only that the patents may also
reach any wired connection. Id. col. 9 ll. 45–51. Though
these statements do not expressly exclude wireless com-
munications from the meaning of “communications path,”
they do not include it, and they discourage that under-
standing. Further, IWS did not present—nor did the
district court consult—any extrinsic evidence, such as
dictionaries, trade literature, expert testimony, or any
other evidence showing that “communications path” was a
term of art or otherwise understood to include wireless
communications at the time of invention.
    Considering the claims as a whole provides no addi-
tional clue that “communications path” includes wireless
communications. Though several dependent claims limit
the communications path to a “two-wire telephone sub-
scriber line” (’895 patent, claims 13, 21, 23, 25) or a “two-
wire line” (’473 patent, claims 6, 21, 27, 28), we agree with
Ruckus that these dependent claims could merely exclude
other types of wired communications paths disclosed in
the specification, such as coaxial cable. See id. at col. 3 ll.
13–23.     The doctrine of claim differentiation—which
encourages us to construe independent claims more

    2  We have used the title of a patent to aid in claim
construction. See, e.g., Exxon Chem. Patents, Inc. v.
Lubrizol Corp., 64 F.3d 1553, 1557 (Fed. Cir. 1995);
Titanium Metals Corp. of Am. v. Banner, 778 F.2d 775,
780 (Fed. Cir. 1985).
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   9

broadly than their dependent claims—therefore does not
necessarily suggest that the “communications path”
recited in the independent claim encompasses wireless
communications. We also have no evidence that the
underlying purpose and disclosed solution of the Terry
patents might evoke wireless communication in the mind
of a skilled artisan. IWS presents no evidence that the
inability to execute collision detection protocols over long
distances was a problem in wireless communication or
that collision detection was even used in that context. We
therefore have no reason to believe that the purpose of the
patents would have implicated wireless communications
within the meaning of “communications path.”
    The canons of claim construction provide additional
reason to limit the scope of the claims to wired communi-
cation. If, after applying all other available tools of claim
construction, a claim is ambiguous, it should be construed
to preserve its validity. Phillips, 415 F.3d at 1327. Be-
cause the specification makes no mention of wireless
communications, construing the instant claims to encom-
pass that subject matter would likely render the claims
invalid for lack of written description. See Gentry Gallery,
Inc. v. Berkline Corp., 134 F.3d 1473, 1480 (Fed. Cir.
1998) (holding that a claim “may be no broader than the
supporting disclosure”). The canon favoring constructions
that preserve claim validity therefore counsels against
construing “communications path” to include wireless
communications.
    We conclude that no intrinsic or extrinsic evidence
suggests that “communications path” encompasses wire-
less communications. Accordingly, we affirm the district
court’s claim constructions and final judgment of non-
infringement based thereon.

                        AFFIRMED
                            COSTS
10 RUCKUS WIRELESS, INC. v. INNOVATIVE WIRELESS SOLUTIONS

   No costs.
  United States Court of Appeals
      for the Federal Circuit
                 ______________________

RUCKUS WIRELESS, INC., CISCO SYSTEMS, INC.,
            Plaintiffs-Appellees

                             v.

    INNOVATIVE WIRELESS SOLUTIONS, LLC,
              Defendant-Appellant
             ______________________

                  2015-1425, 2015-1438
                 ______________________

    Appeals from the United States District Court for the
Western District of Texas in Nos. 1:13-cv-00492-LY, 1:13-
cv-00504-LY, Judge Lee Yeakel.
                _______________________

STARK, Chief District Judge, dissenting. ∗
    The dispositive issue in this case is whether a person
of ordinary skill in the art at the time of the invention of
the Terry patents would understand the “plain and ordi-
nary” meaning of the disputed claim term, “communica-
tions path,” to include wireless communications.          If
wireless communications are not within the scope of the
patent claims, then the judgment of non-infringement

    ∗
       The Honorable Leonard P. Stark, Chief District
Judge, United States District Court for the District of
Delaware, sitting by designation.
2   RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS

must be affirmed. However, if the properly construed
claims include wireless embodiments, then this case
should proceed.
    In affirming the district court’s conclusion that wire-
less communications are outside the scope of the claims,
the majority emphasizes that there is no extrinsic evi-
dence to support the “assumption” of the patentee, Inno-
vative Wireless Solutions (“IWS”), that the plain and
ordinary meaning of “communications path” to a person of
skill in the art at the pertinent time included wireless
communications. I agree that the record lacks this ex-
trinsic evidence.
    However, rather than supporting affirmance, I believe
that the majority’s view requires this court to vacate the
judgment of non-infringement, and the claim construction
order on which it is based, and remand for the district
court to decide whether to provide the parties an oppor-
tunity to present extrinsic evidence. Two factors per-
suade me that this is the proper approach.
    First, in the district court, there was no dispute as to
the plain and ordinary meaning of “communications
path.” Instead, the parties agreed that this meaning
included wireless communications—but disagreed as to
whether that undisputed meaning should be adopted as
the claim construction. Even on appeal, the appellees,
Ruckus Wireless, Inc. and Cisco Systems, Inc. (“Ruckus”),
principally argue for a disclaimer of claim scope, and not
that wireless communications are outside the plain and
ordinary meaning of “communications path.” In these
circumstances, we should not fault the patentee for failing
to come forward with extrinsic evidence. Instead, we
should give the patentee a chance to do so—particularly
because the district court may have to make subsidiary
findings of fact in order to construe the claims. For that
to occur, remand is necessary.
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   3

    Second, although I do not believe the parties’ dispute
should now be resolved on the intrinsic evidence alone, I
disagree with the majority’s assessment of that evidence.
In the unusual circumstances here, it would be preferable
to develop the record instead of making a decision solely
on the basis of inconclusive intrinsic evidence.
    For these reasons, which I explain more fully below, I
respectfully dissent.
                              I
    The majority characterizes Ruckus’s position as being
that “the term ‘communications path’ does not have a
plain and ordinary meaning to a person having ordinary
skill in the art.” Majority Op. at 7. The majority empha-
sizes that “IWS did not present—nor did the district court
consult—any extrinsic evidence, such as dictionaries,
trade literature, expert testimony, or any other evidence
showing that ‘communications path’ was a term of art or
otherwise understood to include wireless communications
at the time of invention.” Id. at 8. It further observes
that “IWS’s argument relies on the assumption that
‘communications path’ has an ordinary meaning which
encompasses both wired and wireless communications”
and faults IWS for not producing evidence to “support
IWS’s assumption that a person of ordinary skill at the
time of the invention would have understood the plain
and ordinary meaning of ‘communications path’ to include
wireless communications.” Id. at 7.
    But the majority makes its own implicit assumption:
that IWS’s failure to present extrinsic evidence is a con-
cession that such supportive evidence does not exist. In
my view, it is far more probable that IWS chose not to
present extrinsic evidence of the plain and ordinary
meaning of the disputed term because Ruckus never
challenged this meaning below.
4   RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS

                              A
    The reason there is no extrinsic evidence as to the
plain and ordinary meaning of “communications path” to
a person of ordinary skill in the art 1 at the time of the
Terry patents’ invention is almost certainly that there
was no dispute on this point in the district court. In the
district court, IWS made clear that it believed the plain
and ordinary meaning of “communications path” was
broad enough to include wireless embodiments. Ruckus
never disputed this. Instead, Ruckus argued that the
specification required a narrower construction. That the
parties’ dispute pertained to whether the term “communi-
cations path” should have its plain and ordinary mean-
ing—as opposed to what that plain and ordinary meaning
was—is evident from the parties’ briefing below, the
transcript of the claim construction hearing, and the
district court’s opinion.

    1    The parties provided the district court with very
little assistance in determining the qualifications or
experience of the person of ordinary skill in the art. In
their briefing, neither side offered a proposed identifica-
tion of such a person. At the claim construction hearing,
when the district court asked, “Who is the person ordinar-
ily skilled in the art at the time of the invention?” counsel
for IWS responded that this was “a factual issue” on
which “neither side has presented a proposal.” Cisco Sys.,
Inc. v. Innovative Wireless Sols., LLC, No. 1:13-CV-00492-
LY, D.I. 54 (“Tr.”) at 35, 37 (W.D. Tex. Jan. 8, 2015).
Ruckus eventually provided its perspective on the qualifi-
cations of one of ordinary skill, but did not explain how
those qualifications should inform the district court’s
construction. See id. at 55-56. On remand, the district
court could direct the parties to develop the record on this
issue.
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   5

    From at least the time the parties submitted their
joint claim construction statement, IWS advocated that
“communications path” be given its “plain and ordinary
meaning in the field.” J.A. 625; see also J.A. 619-22, 626-
27, 633, 655-58. Ruckus did not contend that the content
of IWS’s proposed “plain and ordinary meaning” was in
any way unclear or disputed. Instead, Ruckus proposed
an alternative construction, to limit the claim scope to
wired communications. 2
    In its opening claim construction brief, IWS further
asserted that there was “no reasonable dispute that the
plain and ordinary meaning of ‘communications path’ is
not limited to a wired path.” J.A. 877. Ruckus, in its
briefs, did not disagree.
    Consistent with its briefing, Ruckus did not challenge
IWS’s contention at the claim construction hearing.
Rather, Ruckus characterized the dispute as being that
IWS “say[s] plain and ordinary meaning, and we say
‘wired communication path,’” and argued that “the intrin-
sic record” consisted of “an unmistakable teaching that
this patent is confined to a wired network.” Tr. at 7-9.
When it was his turn, 3 counsel for IWS reaffirmed its
view that:
   [T]here’s no real dispute [about whether] the
   plain and ordinary meaning of the phrase “com-

   2    Ruckus’s proposed construction of “communica-
tions path”—“a wired communications path for exchang-
ing information between two endpoints,” J.A. 625—
incorporates the disputed term itself, another indication
that Ruckus agreed with IWS as to the plain and ordinary
meaning of this term.
    3   At the claim construction hearing, Ruckus pre-
sented its position on this dispute before IWS. Ruckus did
not have a rebuttal.
6   RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS

    munications path” is limited to “wired.” There’s
    no requirement in the word “communication” or
    “path” or “communications path” that’s limited to
    “wired.” There’s been no suggestion or evidence
    that generally in the field of network, if you say
    the phrase “communications path,” that you mean
    “wired.”
Id. at 15. 4
    Reflecting what the parties did and did not argue, the
district court’s opinion notes no dispute as to whether the
plain and ordinary meaning of “communications path”
includes wireless communications. In describing the
parties’ dispute, the court explained that Ruckus relied on
the specification as “clearly demonstrat[ing]” that the
invention’s “sole purpose” related to wired paths. J.A. 19.
The court also noted Ruckus argued that “the patents-in-
suit disclaim” certain embodiments, that “a wired com-
munication path is the defining characteristic of all varia-
tions of the disclosed embodiments,” and that there was a
“purposeful intent to limit the invention’s scope to a wired
communication path.” Id. The district court summarized
IWS’s position as being that “the term should be given its
broadest ordinary meaning consistent with the written
description,” which IWS contended includes wireless
embodiments. Id.

    4    As the majority states, the district court heard a
tutorial just before the claim construction hearing, at
which Ruckus presented expert testimony. Majority Op.
at 6; see also Appellees’ Br. 9, 11; J.A. 807; J.A. 1365 at
Dkt. 49; J.A. 1372 at Dkt. 51. Although the parties have
not provided us with a transcript of the tutorial, there is
no basis to believe it addressed the plain and ordinary
meaning of “communications path” to a person of ordinary
skill in the art.
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS     7

     When it turned to resolving the dispute before it, the
district court stated that it could “depart from the plain
and ordinary meaning of a claim term in only two in-
stances: lexicography and disavowal.” J.A. 20. As neither
side argued that the patentee here was its own lexicogra-
pher, “to conclude that the term requires construction
beyond its plain and ordinary meaning, the court would
need to find ‘that the specification [or prosecution history]
make[] clear that the invention does not include a particu-
lar feature, or is clearly limited to a particular form of the
invention.’” Id. (quoting Hill-Rom Servs., Inc. v. Stryker
Corp., 755 F.3d 1367, 1372 (Fed. Cir. 2014)). Based on
the specification, the court concluded that the Terry
patents “are solely focused on communicating information
packets long distances over wired communication paths”
and, accordingly, construed the claims as being limited to
wired communications. J.A. 20-22.
    At no point in its analysis did the district court men-
tion any dispute as to whether the plain and ordinary
meaning of “communications path,” to a person of ordi-
nary skill in the art reading the Terry patents at the
pertinent time, included wireless communications. There
simply was no dispute on this point. 5 Hence, IWS’s
decision not to present extrinsic evidence as to the plain
and ordinary meaning of “communications path” is entire-
ly understandable.

    5    Counsel for IWS confirmed this at oral argument
before this court, repeatedly stating it was uncontested
below that the ordinary meaning of “communications
path” included wireless communications. Oral Argument
at             12:00,             available             at
http://oralarguments.cafc.uscourts.gov/default.aspx?fl=20
15-1425.mp3; see also id. at 00:40; 01:25. Ruckus ex-
pressed no disagreement with these representations.
8   RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS

                              B
    In this appeal, as below, Ruckus’s principal argument
remains that the intrinsic evidence demonstrates that the
patentee implicitly disclaimed wireless communications.
Ruckus argues that the claims are limited to wired com-
munications because a wired path “is an important core
feature of the invention,” and it is proper to “limit[] claims
to the scope consistently prescribed by the patentee in the
intrinsic record.” Appellees’ Br. 10.
     Ruckus has, however, raised a new argument in this
appeal. Ruckus now faults IWS for “suggest[ing],” with-
out proving, that there is a plain and ordinary meaning of
the disputed claim term “that would be understood by one
of ordinary skill in the art as broad enough to encompass
a wireless path.” Appellees’ Br. 16-17; see also id. at 17
(“IWS, however, did not identify any support that shows
these phrases have a plain and ordinary meaning readily
understood by one of ordinary skill in the art without the
benefit of the context provided by the intrinsic record.”).
Ruckus argues that these evidentiary deficiencies compel
affirmance of a construction excluding wireless embodi-
ments. The majority agrees with Ruckus.
     In my view, the state of the record instead warrants a
remand. As the majority writes, “‘[T]he words of a claim
are generally given their ordinary and customary mean-
ing,’ which 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.’” Majority Op. at 6 (quoting Phillips v.
AWH Corp., 415 F.3d 1303, 1312-13 (Fed. Cir. 2005) (en
banc)). If there is a lack of proof as to that meaning, it is
due to the lack of dispute on this issue below. Hence, we
should remand. See generally Metro. Life Ins. Co. v.
Bancorp Servs., LLC, 527 F.3d 1330, 1336 (Fed. Cir. 2008)
(declining to consider claim construction issue that dis-
trict court did not “expressly” address and remanding to
district court for further proceedings).
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   9

                              C
    Remand is particularly appropriate in this case be-
cause, if the issue in dispute is whether the disputed term
does or does not have a plain and ordinary meaning,
subsidiary factfinding may be necessary to construe the
claim. Although factfinding is often unnecessary in claim
construction, the Supreme Court in its recent decision in
Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc., ex-
plained that sometimes a district court may
   need to look beyond the patent’s intrinsic evidence
   and to consult extrinsic evidence in order to un-
   derstand, for example, the background science or
   the meaning of a term in the relevant art during
   the relevant time period. In cases where those
   subsidiary facts are in dispute, courts will need to
   make subsidiary factual findings about that ex-
   trinsic evidence. These are the “evidentiary un-
   derpinnings” of claim construction that we
   discussed in Markman . . . .
135 S. Ct. 831, 841 (2015) (emphasis added) (citation
omitted). Thus, if the claim construction in this case
turns on the previously-unaddressed question of the plain
and ordinary meaning of the disputed term in the rele-
vant art during the relevant time period, then it is quite
possible that extrinsic evidence will be necessary to
resolve the question.
    Notably, the entirety of the claim construction pro-
ceedings below occurred before the Supreme Court decid-
ed Teva. Remand would allow the district court to
consider these issues in light of the guidance in that case.
10 RUCKUS WIRELESS, INC. v. INNOVATIVE WIRELESS SOLUTIONS

                             II
    In the absence of extrinsic evidence, the majority re-
solves this case based solely on the intrinsic evidence. I
believe this is premature. The intrinsic evidence can only
be fully evaluated after determining what, if anything, is
the plain and ordinary meaning of “communications path”
to one of skill in the art. See Teva, 135 S. Ct. at 841
(explaining that court must resolve disagreements about
knowledge, experiences, and understandings possessed by
person of ordinary skill in the art before proceeding to
“legal analysis [of] whether a skilled artisan would as-
cribe that same meaning to that term in the context of the
specific patent claim under review”); Phillips v. AWH
Corp., 415 F.3d at 1313 (stating that claim construction
“begins” with perspective of person of ordinary skill in the
art).
    But even if this term has no plain and ordinary mean-
ing outside of the context provided by the intrinsic record,
I do not agree with the majority’s conclusion that the
intrinsic record “militates powerfully against” a construc-
tion that encompasses wireless communications. Majority
Op. at 7. As the majority recognizes, the intrinsic evi-
dence “do[es] not expressly exclude wireless communica-
tions from the meaning of ‘communications path.’” Id. at
8. Yet, applying “[t]he canons of claim construction,” 6 the
majority finds in the intrinsic evidence sufficient basis “to

    6   The majority opinion does not mention disclaimer,
although this was the principal basis on which the district
court arrived at the construction which the majority
affirms. Like the majority, I do not decide whether the
record here meets the “exacting” standards for finding a
disclaimer. Thorner v. Sony Comput. Entm’t Am. LLC,
669 F.3d 1362, 1366-67 (Fed. Cir. 2012). Because of the
need for further proceedings, the decision as to whether
there is a disclaimer should wait.
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   11

limit the scope of the claims to wired communication.” Id.
at 9. I disagree.
     The majority cites as evidence of the claims’ scope the
patents’ title: “Communicating Information Packets Via
Telephone Lines.” Id. at 7-8. But even the majority
concedes that the claim scope extends beyond telephone
lines to other “twisted pair wirings.” Furthermore, patent
titles are accorded no more weight in claim construction
than other portions of the specification. See Moore U.S.A.,
Inc. v. Standard Register Co., 229 F.3d 1091, 1111 (Fed.
Cir. 2000) (“[T]he bar on importing limitations from the
written description into the claims applies no less force-
fully to a title.”); Pitney Bowes, Inc. v. Hewlett-Packard
Co., 182 F.3d 1298, 1312 (Fed. Cir. 1999) (patent title is
“near irrelevancy” in claim construction).
     Next the majority observes that the specification de-
scribes “[t]he invention” as “particularly concerned” with
“two wire lines such as telephone subscriber lines.”
Majority Op. at 8 (citing ’895 patent col. 1 ll. 6-10). But
this court does not usually limit claim scope to preferred
embodiments, lest it commit the “cardinal sin” of import-
ing limitations from the specification into the claims. See,
e.g., Hill-Rom, 755 F.3d at 1371 (“[W]e do not read limita-
tions from the embodiments in the specification into the
claims.”); Thorner, 669 F.3d at 1366 (“We do not read
limitations from the specification into claims . . . .”);
Phillips, 415 F.3d at 1320 (describing “reading a limita-
tion from the written description into the claims” as “one
of the cardinal sins of patent law”) (internal quotation
marks omitted).
    Finally, the majority emphasizes that “every embodi-
ment described in the specification utilizes a telephone
wire.” Majority Op. at 8. However, again, claims are not
typically limited to the embodiments disclosed in the
specification, even when just one such embodiment (or
type of embodiment) is disclosed. See Hill-Rom, 755 F.3d
12 RUCKUS WIRELESS, INC. v. INNOVATIVE WIRELESS SOLUTIONS

at 1373 (“The absence of an embodiment teaching a
wireless receiver does not prevent the claimed datalink
from being given its plain and ordinary meaning at the
relevant time.”); see also generally Ormco Corp. v. Align
Tech., Inc., 498 F.3d 1307, 1322 (Fed. Cir. 2007) (“This
court . . . has rejected a claim construction process based
on the ‘essence’ of an invention.”); Allen Eng’g Corp. v.
Bartell Indus., Inc., 299 F.3d 1336, 1345 (Fed. Cir. 2002)
(“It is well settled that there is no legally recognizable or
protected essential element, gist or heart of the invention
in a combination patent.” (internal quotation marks
omitted)).
     Moreover, there is intrinsic evidence that supports
IWS’s position. As is undisputed, wireless technology was
known at the time the Terry patents were invented. See,
e.g., J.A. 19 (“[Ruckus] argues that wireless communica-
tion paths were well-known at the time.”); J.A. 1022. At
least one of the Terry patents, the ’473 patent, includes an
examiner citation to a prior art reference relating to a
wireless local area network (“LAN”) system. See J.A. 86.
In the absence of any express disclaimer, or even dispar-
agement of wireless embodiments, this fact supports
finding wireless communications to be within the scope of
the claims. See Liebel-Flarsheim Co. v. Medrad, Inc., 358
F.3d 898, 909 (Fed. Cir. 2004) (“[A]bsent a clear disclaim-
er of particular subject matter, the fact that the inventor
may have anticipated that the invention would be used in
a particular way does not mean that the scope of the
invention is limited to that context.”) (internal quotation
marks omitted).
   The doctrine of claim differentiation also favors re-
mand. Certain dependent claims—for example, claim 6 of
RUCKUS WIRELESS, INC.   v. INNOVATIVE WIRELESS SOLUTIONS   13

the ’473 patent 7—differ from the claims from which they
depend solely by substituting “two-wire line” for “commu-
nications path.” This suggests that the lower court’s “two-
wire” construction is overly narrow. See Phillips, 415
F.3d at 1315 (“[T]he 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 inde-
pendent claim.”).
    Lastly, I disagree that the claims’ validity is a rele-
vant consideration at this stage of this case. See Majority
Op. at 9. Whether the Terry patents’ written description
is adequate presents a factual question. GlaxoSmithKline
LLC v. Banner Pharmacaps, Inc., 744 F.3d 725, 729 (Fed.
Cir. 2014). The record at present is devoid of clear and
convincing evidence that construing the claims to include
wireless communications would render them invalid for
lack of written description. 8
    As importantly, while this court has “acknowledged
the maxim that claims should be construed to preserve
their validity,” it has “certainly not endorsed a regime in
which validity analysis is a regular component of claim
construction.” Phillips, 415 F.3d at 1327. “Instead, we
have limited the maxim to cases in which the court con-
cludes, after applying all the available tools of claim
construction, that the claim is still ambiguous.” Id.

   7    See ’473 patent col. 20 ll. 12-13 (“6. A method as
claimed in claim 1, wherein the bidirectional communica-
tions path comprises a two-wire line.”).
    8   On remand, if the district court shares the con-
cern as to the adequacy of the Terry patents’ written
description, it might efficiently resolve that question by
staying all discovery and motions practice other than that
relating to the construction of “communications path” and
the written description defense.
14 RUCKUS WIRELESS, INC. v. INNOVATIVE WIRELESS SOLUTIONS

    The majority does not show that the claims here are
ambiguous. To the contrary, the majority appears to find
the intrinsic evidence to be unambiguous. Hence, the
maxim does not apply.
                             III
    I fear that the majority’s decision today deprives a pa-
tentee of the full scope of its patent claims based on the
patentee’s failure to present extrinsic evidence on an issue
that was never in dispute in the district court. On the
current record, it appears that IWS had an entirely rea-
sonable basis to believe it did not need to present extrinsic
evidence. 9 In the proceedings below, nobody—not IWS,
not Ruckus, nor the district court—expressed any doubt
that the plain and ordinary meaning of “communications
path” included wireless communications.
    Accordingly, I believe the most appropriate course of
action is to vacate the district court’s judgment of non-
infringement and its construction of “communications
path” and remand for the district court to provide the
parties an opportunity to present extrinsic evidence before
again construing “communications path.” Thus, I respect-
fully dissent.

    9   It may be that there were facts or circumstances,
not evident from the record before us, that made IWS’s
approach to claim construction unreasonable. It may be,
then, that on remand the district court would find IWS
waived its opportunity to present extrinsic evidence.
Alternatively, the district court might find that Ruckus
effectively stipulated to what IWS has always contended
is the plain and ordinary meaning, avoiding the necessity
of considering extrinsic evidence even on remand. I would
leave these decisions to the district court, which is in the
best position to make them.