  United States Court of Appeals
      for the Federal Circuit
                ______________________

              TEMPO LIGHTING, INC.,
                    Appellant,

                          v.

                    TIVOLI, LLC,
                       Appellee.
                ______________________

                      2013-1140
                ______________________

    Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board, in Reexamination
No. 95/000,067.
                 ______________________

              Decided: February 10, 2014
               ______________________

    MATTHEW C. LAPPLE, Lapple IP Law, P.C., of Irvine,
California, argued for appellant.

    GORDON E. GRAY III, Gray Law Firm, of Long Beach,
California, argued for appellee. With him on the brief
was CRAIG MCLAUGHLIN, Law Office of Craig McLaughlin,
of Costa Mesa, California.
                 ______________________

     Before RADER, Chief Judge, MOORE, and WALLACH,
                    Circuit Judges.
2                          TEMPO LIGHTING, INC.   v. TIVOLI, LLC



RADER, Chief Judge.
    The United States Patent and Trademark Office’s
(PTO) Patent Trial and Appeal Board (Board) reversed
the examiner’s rejection of claims 1–3 and 6–13 of U.S.
Patent No. 6,554,446 (’446 patent). Tempo Lighting, Inc.
(Tempo) appeals that decision. Because the Board’s
decision lacks the support of substantial evidence in the
record and because the Board erred in concluding that
Tempo waived certain arguments, this court vacates the
decision in-part and remands.
                              I.
     Tivoli, LLC (Tivoli) owns the ’446 patent. The ’446
patent relates to a stair-step lighting apparatus that uses
a reflective strip of material to alert users to the edge of a
step in darkened or low-light environments. ’446 patent
col. 1 ll. 23–27. Claim 1, for example, recites:
    1. A lighting apparatus comprising:
        a first extruded portion shaped to mount on
    the nose of a stair step; and,
        a second extruded portion coextruded with
    said first portion and mounted on top of the first
    portion so as to be above the nose of the stair step,
    said second portion comprising a material inert to
    light and selected to have a reflectance factor
    greater than or equal to light gray polyvinyl chlo-
    ride.
’446 patent col. 3 ll. 9–17 (emphasis added).
    Tivoli sued Tempo for patent infringement on Febru-
ary 27, 2004. Tempo later requested inter partes reexam-
ination with the PTO. The PTO granted the request, and
the examiner issued the first Office Action in March 2005,
rejecting all the claims. Shortly afterwards, the district
court stayed the litigation pending the outcome of the
TEMPO LIGHTING, INC.   v. TIVOLI, LLC                     3



reexamination. Over eight years later, the district court
case remains stayed.
     As indicated by the length of the stay, the reexamina-
tion progressed slowly. Tivoli responded to the first Office
Action on May 17, 2005, and Tempo filed comments the
following month. However, the PTO took no further
action until November 2007, when it issued an order
directing Tempo to revise its proposed obviousness rejec-
tions. J.A. 422–26.
    Tempo responded in December 2007 with sixty differ-
ent proposed rejections. On May 20, 2008, the examiner
adopted five of the rejections, but declined to enter the
remainder. J.A. 493–551. The examiner also construed
the “inert to light” limitation present in the disputed
claims. Citing a dictionary, the examiner defined the
term as “a material that either does not react, e.g. by
degrading, when exposed to light or a material that does
not react because it has been treated with or includes
some additive, which inhibits degradation of the material
when exposed to light.” J.A. 500.
     The examiner closed prosecution on May 15, 2009,
maintaining the rejections and the construction of “inert
to light.” In June 2010, the examiner issued a Right of
Appeal Notice. Tivoli appealed the examiner’s rejections,
and the parties fully briefed the Board by October 6, 2010.
Tempo’s brief included arguments supporting the examin-
er’s rejections, and also included alternative grounds for
upholding the examiner’s determination using Tivoli’s
proposed claim construction for “inert to light.” J.A. 905.
Specifically, Tempo asserted that various primary refer-
ences in the examiner’s obviousness rejections anticipated
the claims under Tivoli’s proposed construction. Id.
    The Board issued its decision on February 24, 2012.
The Board first addressed the claim construction for
“inert to light.” It rejected the examiner’s dictionary
definition because Tivoli had defined the term during the
4                          TEMPO LIGHTING, INC.   v. TIVOLI, LLC



original prosecution of the application that issued as the
ʼ446 patent. During original prosecution, Tivoli initially
amended the pending claims to include a “non-
photoluminescent material.” J.A. 1193–1201. The exam-
iner objected to that amendment because the claims
“should recite positive limitations to particularly claim
and distinctly point out features of the invention.” J.A.
1204. In response, Tivoli amended the claims a second
time, stating:
    The office action objects to claims 1, 7, 10 and 14
    because each claim has the limitation “non-
    photoluminescent.” In response, Claims 1, 7 and
    10 have been amended to disclose “a material that
    is inert to light” as a positive limitation indicating
    that the material for the second portion is non-
    photoluminescent and not activated to glow by ab-
    sorbing ambient light.
J.A. 1216. The examiner allowed these claims, and the
application issued as the ’446 patent. J.A. 1225. Thus,
based on the original prosecution history, the Board held
that the proper construction for “inert to light” was “non-
photoluminescent and not activated to glow by absorbing
ambient light.” J.A. 6–9.
    The Board then determined that the rejections of
claims 1–3 and 6–13 were improper. J.A. 15–17. Alt-
hough the Board rejected the examiner’s construction of
“inert to light,” it nevertheless relied on the examiner’s
finding that each of the primary prior art references lacks
the “inert to light” limitation. J.A. 16. Finally, the Board
concluded that Tempo waived its alternative arguments
that certain references anticipate the claims because
Tempo did not file a cross-appeal raising those argu-
ments. J.A. 16 n.4.
    On March, 26, 2012, Tempo filed a request for rehear-
ing. Tempo argued that the Board erred by relying on the
examiner’s factual findings which were predicated on a
TEMPO LIGHTING, INC.   v. TIVOLI, LLC                     5



different construction of “inert to light” than was adopted
by the Board. J.A. 1078–88. Tempo also reiterated its
arguments that the claims are unpatentable under the
Board’s construction of “inert to light.” Id. The Board
denied Tempo’s request for rehearing on September 26,
2012. J.A. 22–27. The Board did not respond to Tempo’s
argument that it improperly relied upon the examiner’s
factual findings under an incorrect claim construction. Id.
The Board instead framed the request as advancing
alternative grounds for unpatentability. J.A. 24. The
Board again concluded that Tempo waived these alterna-
tive arguments by not filing a cross-appeal. J.A. 26.
    On appeal, Tempo advances three arguments. Tempo
argues that the Board erred in construing “inert to light”
differently from the examiner.       Even assuming the
Board’s construction was correct, Tempo also argues that
the Board erred by relying on the examiner’s factual
findings under a different claim construction. Finally,
Tempo argues that it did not waive its arguments con-
cerning alternative grounds for affirming the examiner’s
rejections under Tivoli’s proposed construction of “inert to
light.” This court has jurisdiction under 28 U.S.C.
§ 1295(a)(4)(A).
                               II.
    This court reviews the Board’s legal conclusions de
novo and its factual findings for substantial evidence. In
re Gartside, 203 F.3d 1305, 1315–16 (Fed. Cir. 2000).
Claim construction is a question of law. In re NTP, Inc.,
654 F.3d 1268, 1273 (Fed. Cir. 2011). Anticipation and
prior art teachings present questions of fact. In re NTP,
Inc., 654 F.3d 1279, 1297 (Fed. Cir. 2011). Obviousness is
a question of law based on underlying factual findings.
Id. Finally, this court accepts the Board’s interpretation
of PTO regulations unless that interpretation is “plainly
erroneous or inconsistent with the regulation.” In re
Lovin, 652 F.3d 1349, 1356 (Fed. Cir. 2011).
6                          TEMPO LIGHTING, INC.   v. TIVOLI, LLC



                             III.
    Regarding the claim construction dispute, the exam-
iner concluded that “inert to light” referred to “a material
that does not react, e.g., by degrading, when exposed to
light or a material that does not react because it has been
treated with or includes some additive, which inhibits
degradation of the material when exposed to light.” J.A.
500. The Board found that the examiner erred in constru-
ing the claims, and held that the broadest reasonable
interpretation of the term “inert to light” is “non-
photoluminescent and not activated to glow by absorbing
ambient light.” J.A. 7. This court sustains the Board’s
claim construction.
    The language of the claims in this case does not con-
textually define “inert to light.” Nor does the specification
expressly reference that term. Nonetheless, the intrinsic
evidence supports the Board’s construction. Specifically,
during original examination, Tivoli amended the claims to
recite “inert to light.” At that time, Tivoli also supplied a
meaning for this limitation:
    The office action objects to claims 1, 7, 10 and 14
    because each claim has the limitation “non-
    photoluminescent.” In response, Claims 1, 7 and
    10 have been amended to disclose “a material that
    is inert to light” as a positive limitation indicating
    that the material for the second portion is non-
    photoluminescent and not activated to glow by ab-
    sorbing ambient light.
J.A. 1216 (emphasis added). In claim construction, this
court gives primacy to the language of the claims, fol-
lowed by the specification. Additionally, the prosecution
history, while not literally within the patent document,
serves as intrinsic evidence for purposes of claim con-
struction. This remains true in construing patent claims
before the PTO. See In re Morris, 127 F.3d 1048, 1056
(Fed. Cir. 1997). Here, the prosecution history shows that
TEMPO LIGHTING, INC.   v. TIVOLI, LLC                      7



Tivoli meant for material that is “inert to light” to be
“non-photoluminescent and not activated to glow by
absorbing ambient light.” This intrinsic evidence sup-
ports the Board’s decision.
    In contrast, the examiner’s proposed construction
adds multiple limitations that lack support in any form of
intrinsic evidence. The intrinsic evidence, for example,
contains no reference to the material degrading or not
degrading in response to a reaction with light. Similarly
the intrinsic evidence makes no reference to additives
that would inhibit such a reaction. The examiner instead
relied on an extrinsic dictionary definition of “inert.” J.A.
499. This extrinsic evidence is not irrelevant, but has
relatively little probative value in view of the prevailing
intrinsic evidence. In sum, the examiner erred by resort-
ing to extrinsic evidence that was inconsistent with the
more reliable intrinsic evidence. Bell Atl. Network Servs.
v. Covad Commc’ns Grp., 262 F.3d 1258, 1269 (Fed. Cir.
2001) (“[E]xtrinsic evidence may be used only to assist in
the proper understanding of the disputed limitation; it
may not be used to vary, contradict, expand, or limit the
claim language from how it is defined, even by implica-
tion, in the specification or file history.”).
    This court also reads the Board’s claim construction
with an eye to its consistency and support in the specifica-
tion. When read in context, the specification and claims
as construed by the Board do not present significant
concerns that the claims might be invalid under 35 U.S.C.
§ 112 for lack of written description support (as Tempo
contends). Specifically, when read in context, the specifi-
cation’s isolated reference to “capturing” low level light is
not reasonably viewed as referring to photoluminescence.
’446 patent col. 2 ll. 59–61. And Tempo has not identified
any materials in the ’446 patent that are photolumines-
cent. Thus, nothing in the specification is inconsistent
with the Board’s construction. Cf. Kennecott Corp. v.
Kyocera Int'l, Inc., 835 F.2d 1419, 1423 (Fed. Cir. 1987).
8                         TEMPO LIGHTING, INC.   v. TIVOLI, LLC



    Moreover, the Board properly avoided the circularity
inherent in any attempt to construe claims with an eye to
preserving their validity, a doctrine of “limited utility.”
See Phillips v. AWH Corp., 415 F.3d 1303, 1328 (Fed. Cir.
2005). Thus, even in the unlikely event that it adopted a
construction for “inert to light” that might render the
claims invalid under § 112, the Board did not err in
reaching that meaning based on the intrinsic evidence. In
any event, if the stayed litigation proceeds anew before
the District Court, Tempo will have an opportunity to
challenge the claims under § 112 at that time.
    This court also observes that the PTO is under no ob-
ligation to accept a claim construction proffered as a
prosecution history disclaimer, which generally only binds
the patent owner. However, in this instance, the PTO
itself requested Tivoli rewrite the “non-photoluminescent”
limitation in positive terms. Tivoli complied, and then
supplied clarification about the meaning of the “inert to
light” limitation. J.A. 1216. For all these reasons, this
court affirms the Board’s construction of “inert to light.”
                            IV.
    Having corrected the examiner’s claim construction,
however, the Board erred by relying on factual findings
resting on that incorrect claim construction. In its opin-
ion, the Board states “we agree with Patent Owner that
the combination of prior art does not result in a lighting
apparatus that is ‘inert to light’ when the term is properly
construed. In this regard, the Examiner expressly found
that each of the primary references . . . lacks this claimed
feature.” J.A. 15–16. The Board’s reasoning is deficient.
The Board states that the prior art references do not
disclose the “inert to light” limitation as properly con-
strued, but only cites to the examiner’s findings under the
reversed—and substantially different—claim construc-
tion. On remand, the PTO will have the opportunity to
make new factual findings under the proper construction.
TEMPO LIGHTING, INC.   v. TIVOLI, LLC                     9



                               V.
    Finally, on remand, the Board will also have the op-
portunity to consider Tempo’s alternative arguments for
holding the disputed claims unpatentable. The Board
refused to do so because the arguments “contradict[] the
Examiner’s express findings to the contrary” and Tempo
“chose not to cross-appeal the rejections under 35 U.S.C.
§ 102 over the primary references, which were proposed in
the Request for Reexamination and not adopted by the
Examiner.” J.A. 16 n. 4. The Board’s refusal rests on a
clearly erroneous interpretation of the PTO’s regulations
governing appeals.
    Third-party requester cross-appeals are governed by
37 C.F.R. § 41.61(b). That regulation states, in relevant
part, that “a requester who has not filed a notice of appeal
may file a notice of cross appeal with respect to any final
decision favorable to the patentability, including any final
determination not to make a proposed rejection, of any
original, proposed amended, or new claim of the patent.”
37 C.F.R. § 41.61(b) (emphasis added). Thus, one of the
threshold conditions for a cross-appeal is a final decision
favorable to patentability. In this case, the examiner
rejected all the claims. Thus, the record presented no
decision favorable to patentability for Tempo to appeal.
     Contrary to the Board’s assertion, each of the examin-
er’s determinations against Tempo’s proposed rejections is
not a distinct decision favorable to patentability necessi-
tating an appeal. The regulation uses the word “includ-
ing” to clarify that any final determination not to make a
proposed rejection is subordinate to, and contained with-
in, the final decision favorable to patentability. The Right
of Appeal Notice in this case provided a single final deci-
sion concerning the patentability of the disputed claims.
J.A. 813–14. The decision was that all the claims are
unpatentable, a decision decidedly unfavorable to patent-
ability.
10                        TEMPO LIGHTING, INC.   v. TIVOLI, LLC



    Further, nothing in the regulation or procedure re-
quires Tempo to raise its arguments on cross-appeal.
That is, even if the regulation gave Tempo the right to
raise these arguments in a cross-appeal, and thus obtain
the benefit of additional briefing, the regulation simply
says that Tempo “may” do so, not that it must. A Notice
of Proposed Rulemaking issued by the PTO supports this
conclusion. Streamlined Patent Reexamination Proceed-
ing, 76 Fed. Reg. 22,854, 22,859–60 (April 25, 2011). In
that notice, the PTO proposed a rule change prohibiting
cross-appeals of non-adopted rejections where all the
claims stood rejected on other grounds. Id. This change
was to avoid duplicative and cumulative briefing (which
admits that the same arguments may be raised on direct
appeal), and to accord the Office’s appeals practice with
that of the courts. Id.; cf. Aventis Pharma S.A. v. Hospira,
Inc., 637 F.3d 1341, 1343 (Fed. Cir. 2011) (“Where, as
here, the district court has entered a judgment of invalidi-
ty as to all of the asserted claims, there is no basis for a
cross-appeal . . . [on] additional claims for invalidity.”).
Thus, even under Tivoli’s theory, the Board’s decision is
contradicted by this official PTO publication. While the
PTO notice is not dispositive, nor binding, it supports the
conclusion that the Board erred in construing § 41.61(b).
    Finally, where a prevailing party seeks to enlarge its
own rights under the judgment or to lessen the rights of
its adversary, a cross-appeal generally is needed. Lazare
Kaplan Int’l, Inc. v. Photoscribe Techs., Inc., 714 F.3d
1289, 1293 (Fed. Cir. 2013). But where claims have
already been adjudicated invalid, a cross-appeal regard-
ing additional invalidity arguments is generally improper.
Aventis, 637 F.3d at 1343. In this case, Tempo has the
right to defend the examiner’s final decision on any
ground supported by the record. Rexnord Indus., LLC v.
Kappos, 705 F.3d 1347, 1356 (Fed. Cir. 2013). Through-
out the reexamination, Tempo argued that the primary
references anticipate the claims under Tivoli’s construc-
TEMPO LIGHTING, INC.   v. TIVOLI, LLC                    11



tion. J.A. 440–47. While Tempo argued in favor of the
examiner’s construction and rejections, this did not fore-
close Tempo from also advancing arguments under the
construction proposed by Tivoli. Contrary to the Board’s
decision, and Tivoli’s arguments, Tempo’s conduct does
not rise to the level of waiver or invoke judicial estoppel.
Accordingly, the Board erred by not considering Tempo’s
additional arguments.
                               VI.
    In sum, this court affirms the Board’s construction of
“inert to light.” However, the Board’s decision reversing
the examiner’s rejections is vacated.      Similarly, the
Board’s conclusion that Tempo waived certain arguments
is also vacated. This court remands to the Board for
proceedings consistent with this opinion. As this reexam-
ination has lasted nearly a decade, this court urges the
PTO to provide a speedy resolution to this dispute as
envisioned under 35 U.S.C. § 314(c).
  AFFIRMED-IN-PART, VACATED-IN-PART AND
               REMANDED
