  United States Court of Appeals
      for the Federal Circuit
                ______________________

                   INDACON, INC.,
                   Plaintiff-Appellant

                           v.

                  FACEBOOK, INC.,
                  Defendant-Appellee
                ______________________

                      2015-1129
                ______________________

   Appeal from the United States District Court for the
Western District of Texas in No. 5:10-cv-00966-OLG,
Judge Orlando L. Garcia.
                ______________________

                 Decided: June 6, 2016
                ______________________

    PRATIK A. SHAH, Akin, Gump, Strauss, Hauer & Feld,
LLP, Washington, DC, argued for plaintiff-appellant. Also
represented by ZE-WEN JULIUS CHEN, EMILY CURTIS
JOHNSON, JAMES EDWARD TYSSE.

    THOMAS G. HUNGAR, Gibson, Dunn & Crutcher LLP,
Washington, DC, argued for defendant-appellee. Also
represented by BLAIR A. SILVER, LUCAS C. TOWNSEND;
HEIDI LYN KEEFE, MARK R. WEINSTEIN, Cooley LLP, Palo
Alto, CA; MICHAEL GRAHAM RHODES, San Francisco, CA.
                ______________________
2                             INDACON, INC.   v. FACEBOOK, INC.



    Before NEWMAN, REYNA, and STOLL, Circuit Judges.
STOLL, Circuit Judge.
    Following the district court’s claim construction order,
Indacon, Inc. and Facebook, Inc. stipulated to nonin-
fringement, and the district court entered final judgment
in favor of Facebook. Indacon appeals, disputing the
district court’s construction of several claim terms. Be-
cause the district court correctly construed the claim
terms “alias,” “custom link,” “custom linking relation-
ship,” and “link term,” we affirm.
                        BACKGROUND
     Indacon owns U.S. Patent No. 6,834,276, which is
directed to a system and method for searching, indexing,
perusing, and manipulating files in a database, particu-
larly through the insertion of automatically generated
hyperlinks. ’276 patent col. 3 ll. 50–54, col. 4 ll. 56–58,
col. 5 ll. 34–47. Exemplary claim 1 recites:
    1. A data acquisition and perusal system, compris-
    ing:
    a database selection module that enables selection
    of a plurality of files for inclusion into at least one
    selectable database;
    a link module that enables custom links to be de-
    fined between selected terms of selected files of
    the at least one database;
    wherein the link module enables association of
    any link term with any of the plurality of files in
    the at least one selectable database; and
    wherein the link module enables at least one alias
    term to be defined for the any link term to enable
    a link to be established between the at least one
    alias term and the any of the plurality of files;
INDACON, INC.   v. FACEBOOK, INC.                           3



    a database index generator module that enables
    generation of a searchable index of the data con-
    tained in the at least one selectable database, in-
    cluding the custom links, the generator module
    enabling only valid custom links to be added to the
    searchable index; and
    a search module that enables a search of the
    searchable index to be performed according to a
    search criterions.
Id. col. 34 l. 56 – col. 35 l. 9 (emphases added).
    Indacon filed a patent infringement suit against
Facebook, alleging that the software architecture for
Facebook’s social network infringes claims 1–4 and 8–11
of the ’276 patent. The district court construed several
claim terms in the ’276 patent. Following claim construc-
tion, the parties stipulated to noninfringement, and the
district court entered final judgment in Facebook’s favor.
On appeal, Indacon disputes the district court’s construc-
tion of four claim terms: “alias,” “custom link,” “custom
linking relationship,” and “link term.” We have jurisdic-
tion pursuant to 28 U.S.C. § 1295(a)(1).
                          DISCUSSION
    “The ultimate construction of the claim is a legal
question and, therefore, is reviewed de novo.” Info-Hold,
Inc. v. Applied Media Techs. Corp., 783 F.3d 1262, 1265
(Fed. Cir. 2015). While subsidiary factual findings re-
garding extrinsic evidence are reviewed for clear error, we
review claim construction based solely upon intrinsic
evidence de novo. Teva Pharm. USA, Inc. v. Sandoz, Inc.,
135 S. Ct. 831, 841 (2015). Because the district court
considered only intrinsic evidence in construing the
disputed claim terms, our review here is de novo.
    “[T]he 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.’”
4                            INDACON, INC.   v. FACEBOOK, INC.



Phillips v. AWH Corp., 415 F.3d 1303, 1315 (Fed. Cir.
2005) (en banc) (quoting Vitronics Corp. v. Conceptronic,
Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996)). The prosecu-
tion history of a patent is also part of the intrinsic evi-
dence and “can often inform the meaning of the claim
language by demonstrating how the inventor understood
the invention and whether the inventor limited the inven-
tion in the course of prosecution.” Id. at 1317.
                          I. Alias
    Several of the claims require a link to be established
between an “alias” or “alias term” and a plurality of files.
The district court construed the claim term “alias” as a
“textual expression that the user can define to serve as an
alternative name or label.” Indacon, Inc. v. Facebook, Inc.
(Claim     Constr.     Order),     No.    5:10-cv-966-OLG,
Dkt. No. 111, at 22 (W.D. Tex. Sept. 6, 2013) (emphasis
added). Indacon acknowledges that “alias” and “alias
term” are used interchangeably in the ’276 patent. Inda-
con argues that this term encompasses a “textual or
graphical hyperlink,” and not just “textual expression.”
Appellant Br. 19. Thus, Indacon essentially raises two
disputes with the district court’s construction: (1) whether
“alias” encompasses graphical expression as well as
textual expression, and (2) whether an “alias” is a hyper-
link.
     We agree with the district court that “alias” and “alias
term” are limited to textual expression. The district court
first construed “term” as “textual expression, such as
words,” finding an express definition of “term” in the
specification as “words, numbers, spaces, etc.” Claim
Constr. Order at 17–18 (citing ’276 patent col. 12 l. 55).
Then, finding that the specification described an alias as a
term, the district court looked to this construction of
“term” to determine that “alias” is similarly limited to
textual expression.
INDACON, INC.   v. FACEBOOK, INC.                           5



     Indacon argues that the district court erred by basing
its construction of “alias” on its construction of “term.”
Indacon has not appealed the district court’s construction
of “term,” but instead argues that “alias” is not dependent
on the meaning of “term.” We agree with the district
court’s approach and conclusion regarding the construc-
tion of “alias.” The ’276 patent defines “term” by referring
to forms of textual expression (“words, numbers, spaces,
etc.”). See id. As the district court explained, the use of
“etc.” in this definition implies additional, but similar
forms of expression and does not reasonably encompass
graphical expression. Indacon also recognizes that exem-
plary claim 1 is not directed to just an “alias,” but actually
requires an “alias term.” Thus, Indacon’s argument that
the construction of “term” is irrelevant to the construction
of “alias” is unconvincing.
     Further, nothing in the specification suggests that
“alias” encompasses graphical expression. Instead, the
specification consistently describes an alias as a term,
which, as explained above, is limited to textual expres-
sion. The “Summary of the Invention” introduces the
concept of an “alias,” explaining: “The link module may
further enable at least one alias term to be defined for any
selected link term to enable a link to be established
between each alias term and any of the files in the data-
base.” ’276 patent col. 5 ll. 64–67 (emphases added).
Similarly, all examples of an “alias” in the specification
consist of textual expression. See id. col. 11 ll. 34–36
(“For example, the user may define the terms ‘grape’,
‘tomato’, ‘raspberry’, etc., as aliases of a link term ‘vine
fruit’.”) (emphases added); id. col. 24 ll. 46–48 (“For ex-
ample, a user may want to use aliases or synonyms so
that ‘equine’ is also linked when ‘horse’ is the primary
pattern.”) (emphasis added). The prosecution history also
fails to support an interpretation of an “alias” encompass-
ing graphical expression.
6                            INDACON, INC.   v. FACEBOOK, INC.



     Indacon uses the specification’s reference to file for-
mats that may contain graphical elements as support for
its view that an “alias” can be graphical. See, e.g., id.
col. 10 ll. 15–17, col. 22 l. 59 (referencing HTML and RTF
files). But nothing in the specification ties these file
types, or their potentially graphical elements, to an
“alias.” To the contrary, with respect to RTF files, the
specification teaches “discard[ing] all image byte sequenc-
es without affecting the absolute position determination
of visible characters in words.” Id. col. 22 ll. 63–65. We
find no support in the intrinsic evidence for Indacon’s
assertion that the claimed alias can be graphical.
     We also agree with the district court that an “alias” is
not a hyperlink, contrary to Indacon’s assertions. The
specification explains that “[t]he link module may further
enable at least one alias term to be defined for any select-
ed link term to enable a link to be established between
each alias term and any of the files in the database.” Id.
col. 5 ll. 64–67. As such, a link can be established to
connect an “alias” or other link term to files in the data-
base, but the alias is not itself the link. Thus, we adopt
the district court’s construction of “alias” as a “textual
expression that the user can define to serve as an alterna-
tive name or label.”
     II. Custom Link, Custom Linking Relationship,
                    and Link Term
    The district court construed “custom link” as “a link
the user can define using a chosen term that allows each
instance of the term in the plurality of files to be identi-
fied and displayed as a link to a file chosen by the user,
without modifying the original database files”; “custom
linking relationship” as “a linking relationship the user
can define using a chosen term that allows each instance
of the term in the plurality of files to be identified and
displayed as a link to a file chosen by the user, without
modifying the original database files”; and “link term” as
INDACON, INC.   v. FACEBOOK, INC.                           7



“a term chosen by a user that can be displayed as a link to
a file specified by the user whenever the user encounters
the term in the plurality of files.” Claim Constr. Order at
26–27 (emphases added). Indacon raises a single issue
with respect to the constructions of “custom link,” “custom
linking relationship,” and “link term” (collectively, “the
link claim terms”), and does not make any distinct argu-
ments for these individual claim terms.
    Specifically, Indacon objects to the district court’s con-
structions of the link claim terms to the extent they
exclude creation of a link for less than all instances of a
defined term, disputing the district court’s construction
that allows each instance of the defined term to be identi-
fied and displayed as a link. We disagree and adopt the
district court’s constructions of the link claim terms as
being limited to allowing each instance of a link term to
be identified and displayed as a link.
     Facebook argues that the link claim terms have no
accepted meaning in the art. We agree with Facebook
that these terms have no plain or established meaning to
one of ordinary skill in the art. As such, they ordinarily
cannot be construed broader than the disclosure in the
specification. Irdeto Access, Inc. v. Echostar Satellite
Corp., 383 F.3d 1295, 1300 (Fed. Cir. 2004) (“[A]bsent
such an accepted meaning [in the art], we construe a
claim term only as broadly as provided for by the patent
itself.”). The specification explains that “[t]he link module
enables association of any selected link term with any of
the plurality of files in the selectable database.” ’276
patent col. 5 ll. 62–64 (emphasis added). The specification
repeatedly demonstrates that all link terms are capable of
being identified and displayed as a link. See, e.g., id.
col. 11 ll. 29–32 (“[W]hen a link term is encountered in a
file or document, the link term is indicated or otherwise
highlighted so that the user can select the indicated link
term to jump to the linked file.”) (emphases added); id.
col. 30 ll. 22–26 (“A user can instruct the database index
8                            INDACON, INC.   v. FACEBOOK, INC.



generator to insert custom links by entering a custom link
word in a New Custom Link Word edit box and then
entering a path and name of a file or document to which
all such words should link in the File to Link To edit
box.”) (emphasis added); id. col. 30 ll. 34–37 (“[W]henever
a user encounters the custom link word in any document
displayed in the document view window, except the corre-
sponding file to link to file, it is set off from surrounding
text.”) (emphases added). Thus, we agree with the district
court that, consistent with the teachings of the specifica-
tion, the link claim terms are properly construed as
allowing each instance of a defined term to be identified
and displayed as a link.
    The prosecution history provides additional support
for the district court’s constructions of the link claim
terms. In distinguishing prior art, the patentees stated:
    Applicants’ invention provides a user with a link-
    ing control panel in which the user can designate
    a specific file to be linked with every instance of a
    specified word (and any associated alias terms) in
    the database. After the index is generated, the
    program displays every instance of that custom
    term (and its alias terms, if any) as a hyperlink to
    the designated file. . . . These innovations distin-
    guish Applicants’ invention from [the prior art].
Joint Appendix (“J.A.”) 1182–83 (emphases added). The
patentees then summarized the differences between
“Applicants’ Invention” and the prior art, explaining that
their invention “[e]nables user[s] to associate all instances
of a specified word with a specific file.” J.A. 1186 (empha-
sis added).
    Facebook argues that these statements in the prose-
cution history, consistent with the specification, provide
further evidence that the patentees understood the inven-
tion as limited to allowing each instance of a defined term
to be identified and displayed as a link. But, to the extent
INDACON, INC.   v. FACEBOOK, INC.                        9



these claim terms might otherwise have a broader mean-
ing in the art, Facebook argues in the alternative that the
prosecution history evidences a clear and unmistakable
disclaimer of claim scope. We agree that the patentees’
description of their invention during prosecution as
allowing every instance or all instances of designated
terms to be linked to a file bolsters the district court’s
constructions. Because the link claim terms lack a plain
or ordinary meaning in the art, and because the specifica-
tion suggests limiting the scope of these claim terms to
allowing each instance of a defined term to be identified
and displayed as a link, we need not determine whether
the patentees’ statements during prosecution rise to the
level of clear and unmistakable disclaimer.
     In response, Indacon argues that because the refer-
ences to “every instance” in the prosecution history were
not the “critical contrast that applicants were trying to
make over the cited reference,” these statements cannot
form the basis for disavowal. Appellant Reply Br. 12
(citation and internal quotation marks omitted). As
explained above, we need not find disclaimer where the
specification does not permit a broader interpretation of
these claim terms and the terms otherwise lack an ordi-
nary meaning in the art. Moreover, “the interested public
has the right to rely on the inventor’s statements made
during prosecution, without attempting to decipher
whether the examiner relied on them, or how much
weight they were given.” Fenner Invs., Ltd. v. Cellco
P’ship, 778 F.3d 1320, 1325 (Fed. Cir. 2015). Here, the
patentees repeatedly described their invention both in the
specification and the prosecution history as allowing
“every instance” or “all instances” of a defined term to be
identified and displayed as a link. J.A. 1182–83, 1186.
Under these circumstances, the district court did not err
in limiting the link claim terms as such.
    Finally, Indacon argues that claim differentiation pre-
cludes the district court’s constructions of the link claim
10                             INDACON, INC.   v. FACEBOOK, INC.



terms because certain claims recite linking instances
while other claims recite linking all instances of the link
terms. Specifically, Indacon points, on the one hand, to
claims 2 and 9, which recite “wherein the link module is
operable to link instances of the one or more text strings
in the selected files” (claim 2) and “wherein the step of
defining the linking relationships includes . . . linking
instances of the one or more text strings in the selected
files” (claim 9). ’276 patent col. 35 ll. 20–21, col. 37 ll. 29–
32 (emphases added). In contrast, Indacon points to
claims 14 and 15, which both recite “automatically gener-
ating links between all instances of the link term within
the plurality of selected source files and the designated
file.” Id. col. 38 ll. 65–67, col. 40 ll. 1–3 (emphasis added).
Importantly, however, all of claims 2, 9, 14, and 15 are
independent claims, and we have declined to apply the
doctrine of claim differentiation where, as here, the claims
are not otherwise identical in scope. See World Class
Tech. Corp. v. Ormco Corp., 769 F.3d 1120, 1125–26
(Fed. Cir. 2014); Andersen Corp. v. Fiber Composites,
LLC, 474 F.3d 1361, 1370 (Fed. Cir. 2007). Further,
“[a]lthough claim differentiation is a useful analytic tool,
it cannot enlarge the meaning of a claim beyond that
which is supported by the patent documents, or relieve
any claim of limitations imposed by the prosecution
history.” Fenner, 778 F.3d at 1327.
     Thus, we adopt the district court’s constructions of the
link claim terms. “Custom link” is properly construed as
“a link the user can define using a chosen term that
allows each instance of the term in the plurality of files to
be identified and displayed as a link to a file chosen by
the user, without modifying the original database files”;
“custom linking relationship” is properly construed as “a
linking relationship the user can define using a chosen
term that allows each instance of the term in the plurality
of files to be identified and displayed as a link to a file
chosen by the user, without modifying the original data-
INDACON, INC.   v. FACEBOOK, INC.                         11



base files”; and “link term” is properly construed as “a
term chosen by a user that can be displayed as a link to a
file specified by the user whenever the user encounters
the term in the plurality of files.”
                         CONCLUSION
    We find no error in the district court’s constructions of
“alias,” “custom link,” “custom linking relationship,” and
“link term.” As such, we affirm the judgment of nonin-
fringement.
                         AFFIRMED
