  United States Court of Appeals
      for the Federal Circuit
             __________________________

BELKIN INTERNATIONAL, INC., CISCO LINKSYS
                  L.L.C.,
  D-LINK SYSTEMS, INC., AND NETGEAR, INC.,
                Appellants,
                          v.
        DAVID J. KAPPOS, DIRECTOR,
  UNITED STATES PATENT AND TRADEMARK
                  OFFICE,
                  Appellee,
                         AND

               OPTIMUMPATH, LLC,
                    Appellee.
             __________________________

                      2012-1090
            (Reexamination No. 95/001,089)
             __________________________

    Appeal from the United States Patent and Trademark
Office, Board of Patent Appeals and Interferences.
              ____________________________

               Decided: October 2, 2012
            ____________________________
BELKIN INTL   v. KAPPOS                                 2


    DAVID L. MCCOMBS, Haynes and Boone, LLP, of Dal-
las, Texas, argued for appellants. With him on the brief
was DEBRA J. MCCOMAS.

    SCOTT C. WEIDENFELLER, Associate Solicitor, United
States Patent and Trademark Office, of Alexandria,
Virginia, argued for appellee, United States Patent and
Trademark Office. With him on the brief were RAYMOND
T. CHEN, Solicitor, and NATHAN K. KELLEY, Associate
Solicitor.

    TONY D. ALEXANDER, Technology Legal Counsel, LLC,
of Augusta, Georgia, argued for Appellee, Optimumpath,
LLC.
              __________________________

Before RADER, Chief Judge, LOURIE and WALLACH, Circuit
                       Judges.
LOURIE, Circuit Judge.
    Belkin International, Inc. (“Belkin”) appeals from the
decision of the Board of Patent Appeals and Interferences
of the United States Patent and Trademark Office
(“PTO”) on inter partes reexamination that it lacked
jurisdiction to consider arguments based on three refer-
ences that the Director had previously determined did not
raise a substantial new question of patentability. 1 Be-


   1    The Leahy–Smith America Invents Act amended
the inter partes reexamination provisions. See Leahy–
Smith America Invents Act, Pub. L. No. 112–29, § 6, 125
Stat. 284, 299–305 (2011) (“AIA”). Those amendments do
not apply here because the request for inter partes reex-
amination in this case was filed before the date of enact-
ment, September 16, 2011. Id. We thus express no
opinion on the applicability of the AIA provisions to the
current case.
3                                      BELKIN INTL   v. KAPPOS


cause the Board did not err in refusing to consider the
issues that the Director found not to raise a substantial
new question of patentability, we affirm.
                       BACKGROUND
     Belkin filed a request for inter partes reexamination of
U.S. Patent 7,035,281 (the “’281 patent”), which is di-
rected to a wireless router. The request alleged ten
substantial new questions of patentability regarding
claims 1–32 of the ’281 patent based on four prior art
references: (1) Wireless LAN: basic knowledge and appli-
cation case studies, Transistor Gijutsu, Oct. 1, 1999
(“Transistor Article”); (2) Michael Taht & Greg Retkowski,
Wireless Router Howto (1998), http://www.rage.net/
wireless/wireless-howto.html (“Howto Guide”); (3) U.S.
Patent 6,591,306 (“Redlich”); and (4) U.S. Patent
6,560,217 (“Peirce”). The Director determined that the
first three references did not raise a substantial new
question of patentability, but that the issue of anticipa-
tion by Peirce did raise such a question as to claims 1–3
and 8–10. Accordingly, the Director ordered reexamina-
tion of claims 1–3 and 8–10.
    Belkin filed a petition pursuant to 37 C.F.R. §§ 1.927
and 1.181 to have the Director review the denial of reex-
amination of claims 4–7 and 11–32. That petition was
denied, and the status of those claims is not part of this
appeal. Belkin did not, however, file a petition to review
the determination that the issues based on the Transistor
Article, the Howto Guide, and Redlich did not raise sub-
stantial new questions of patentability concerning claims
1–3 and 8–10.
    The examiner then issued an Action Closing Prosecu-
tion (“ACP”) in the reexamination addressing only Bel-
kin’s proposed rejection of claims 1–3 and 8–10 as
anticipated by Peirce. A Right of Appeal Notice (“RAN”)
BELKIN INTL   v. KAPPOS                                  4


was issued, again addressing only anticipation by Peirce.
Belkin appealed to the Board, challenging the examiner’s
failure to make rejections involving the three references
that the Director determined did not raise a substantial
new question of patentability.
     On appeal, the Board determined that it did not have
jurisdiction to decide whether a substantial new question
of patentability exists regarding the Transistor Article,
the Howto Guide, and Redlich, because that determina-
tion was statutorily non-appealable under 35 U.S.C. §
312(c). The Board also held that there had been no final
decision on patentability regarding the three references,
and thus there was nothing to appeal under 35 U.S.C.
§ 315(b) and 37 C.F.R. § 41.61. The Board then affirmed
the examiner’s findings with regard to Peirce. On rehear-
ing, the Board declined to modify its decision and specifi-
cally noted that Belkin had failed to file a petition under
37 C.F.R. § 1.927 to review the Director’s determination
that there was no substantial new question of patentabil-
ity for the issues based on the three references regarding
claims 1–3 and 8–10.
                          DISCUSSION
    We review the Board’s legal conclusions, including
whether the Board possessed jurisdiction, de novo. In re
Gartside, 203 F.3d 1305, 1315 (Fed. Cir. 2000). Statutory
interpretation is a question of law that we likewise review
de novo. In re Kathawala, 9 F.3d 942, 945 (Fed. Cir.
1993). “When statutory interpretation is at issue, the
plain and unambiguous meaning of a statute prevails in
the absence of clearly expressed legislative intent to the
contrary.” In re Donaldson Co., 16 F.3d 1189, 1192–93
(Fed. Cir. 1994) (en banc). We also afford substantial
deference to the PTO’s interpretation of its own regula-
tions unless that interpretation is plainly erroneous or
5                                     BELKIN INTL   v. KAPPOS


inconsistent with the regulation in situations of ambigu-
ity. In re Lovin, 652 F.3d 1349, 1353 (Fed. Cir. 2011).
     Belkin argues that the Board has jurisdiction to con-
sider on reconsideration prior art found not to raise a
substantial new question of patentability on inter partes
reexamination when reexamination is subsequently
granted for the same claim on another reference. Belkin
views reexamination as a two-step procedure: (1) deter-
mining whether a substantial new question of patentabil-
ity exists; and (2) if so, determining whether the claims
are patentable over all prior art. Belkin concedes that the
first step is not appealable under § 312(c). But Belkin
contends that once a substantial new question of pat-
entability affecting a claim is found, all prior art must be
considered, including prior art found previously not to
raise a substantial new question of patentability.
    The Director responds that § 312(c) bars the Board
from considering prior art not found to raise a substantial
new question of patentability even though a substantial
new question of patentability was found with regard to
another reference. In support of that position, the Direc-
tor argues that reexamination is ordered only “for resolu-
tion of the question” identified by the Director as a
substantial new question of patentability, not those
questions raised by the requester that have been deter-
mined not to rise to that level. As Peirce was the only
reference found to raise a substantial new question of
patentability, the Director argues that the resulting
reexamination was properly limited to that question.
    We agree with the Director that the Board did not err
in not considering issues that the Director had found not
to raise a substantial new question of patentability con-
cerning claims 1-3 and 8-10. Such an issue is non-
appealable.
BELKIN INTL   v. KAPPOS                                   6


    At the outset, an inter partes reexamination is a two-
step process. First, the Director must make a determina-
tion “whether a substantial new question of patentability
affecting any claim of the patent is raised by the request
[under § 311], with or without consideration of other
patents or printed publications.” 35 U.S.C. § 312(a). The
statute is clear that that decision is “final and non-
appealable.” § 312(c).
    Second, after the Director has determined that there
is a substantial new question of patentability affecting a
claim with respect to prior art, an inter partes reexamina-
tion is ordered “for resolution of the question.” 35 U.S.C.
§ 313. The question to be resolved is the substantial new
question of patentability determined by the Director. If
the Director determines that there is no substantial new
question of patentability, no reexamination is conducted.
The issue in this appeal is whether a prior determination
that an argument based on a given reference does not
raise a substantial new question of patentability as to a
claim when such a question was raised with respect to
certain other prior art is appealable to the Board and to
this court. To answer that question, we first turn to the
language of the statute.
    The statute requires the Director to order reexamina-
tion “for resolution of the question.” § 313. The statute is
clear that that “question” is the same substantial new
“question” of patentability found by the Director under
§ 312(a). The statutory framework thus requires that an
issue must raise a “substantial new” question of pat-
entability, as determined by the Director, with respect to
cited prior art before it can be considered during inter
partes reexamination. Accordingly, an issue that has
been determined by the Director not to raise a substantial
new question of patentability with respect to certain other
prior art cannot later be considered by the examiner and
7                                     BELKIN INTL   v. KAPPOS


ultimately the Board. Instead, if a requester disagrees
with the Director’s determination that no substantial new
question of patentability with respect to certain prior art
has been raised, 37 C.F.R. § 1.927 permits the requester
only to file a petition to the Director for review of that
decision. Belkin did not file such a petition here with
respect to claims 1–3 and 8–10.
    Inter partes reexamination is not totally limited to
those issues suggested by the requester that present a
substantial new question of patentability. Indeed, the
PTO may make any new rejection, as long as that rejec-
tion also meets the substantial new question of pat-
entability requirement. See 35 U.S.C. § 303(a) (“On his
own initiative, and any time, the Director may determine
whether a substantial new question of patentability is
raised by patents and publications discovered by him . . .
.”). Thus, the scope of reexamination may encompass
those issues that raise a substantial new question of
patentability, whether proposed by the requester or the
Director, but, unless it is raised by the Director on his
own initiative, it only includes issues of patentability
raised in the request under § 311 that the Director has
determined raise such an issue. It otherwise may not
include other prior art than what constituted the basis of
the Director’s determination of a substantial question of
patentability.
    In this case, the Director determined, in part, that the
issues based on the first three references cited by Belkin
did not raise a substantial new question of patentability
regarding claims 1–3 and 8–10. Under § 312(c), that
decision is final and non-appealable. But the Director
also determined that one issue based on anticipation by
another reference, Peirce, did raise such a question. At
that point, the Director was entitled to, and did, order
reexamination for resolution of that single question. The
BELKIN INTL   v. KAPPOS                                     8


scope of the resulting reexamination was then limited to
answering that question of patentability, anticipation by
Peirce. Belkin, at that point, could only raise the three
references if they were necessary to rebut findings of fact
by the examiner or as a response to the patent owner
relevant to answering that single patentability question.
See 37 C.F.R. § 1.948(a). Here, Belkin has not argued
that the three references were cited for such a purpose,
and the limited record before us does not suggest that
they were. Thus, the Board was correct not to consider
the previously raised and rejected issues based on the
other three references.
    Belkin argues that such a result is inconsistent with
the appeals statutes, 35 U.S.C. §§ 134(c) and 315(b), and
regulations such as 37 C.F.R. § 41.61(a)(2). Those stat-
utes grant rights to the requester to appeal a “final deci-
sion . . . favorable to the patentability of any . . . claim.”
§§ 134(c), 315(b).     Similarly, § 41.61(a)(2) specifically
allows the requester to appeal “any final decision favor-
able to the patentability, including any final determina-
tion not to make a proposed rejection, of any . . . claim.”
Id. Belkin argues that the examiner’s decision not to
reject claims 1–3 and 8–10 based on the issues deter-
mined not to raise a substantial new question was a
decision favorable to patentability.
     We disagree with Belkin’s position because there was
no final decision favorable to patentability regarding the
issues based on the three references. First, the Director’s
determination that an issue does not raise a substantial
new question of patentability is not a decision favorable to
patentability. Lack of a substantial new question of
patentability is not a favorable decision on patentability.
Indeed, it cannot be one, as the decision on the substan-
tial new question preceded the actual reexamination, and
merely raised a “question” to be answered. Furthermore,
9                                      BELKIN INTL   v. KAPPOS


it is explicitly non-appealable under § 312(c). To allow an
otherwise non-appealable decision by the Director to
become appealable simply by raising it a second time
during the later reexamination would impermissibly
circumvent the statutory bar on appeals.
    Secondly, if there had been any doubt in this case, the
examiner made clear that she had not made any pat-
entability decision with regard to those three references.
The ACP and the RAN addressed only Peirce. The Exam-
iner’s Answer likewise stated that the only finding to be
reviewed on appeal was the rejection in light of Peirce.
The only adverse decision Belkin received with respect to
those three references was the Director’s determination
that the proposed rejection based on the three references
did not raise a substantial new question of patentability.
Belkin chose not to petition for review of that determina-
tion.
    Belkin argues that it did not petition for review of
claims 1–3 and 8–10 because, in accordance with the
Manual of Patent Examination and Procedure (“MPEP”)
§ 2648, it believed that those claims would be reexamined
in view of “all prior art,” including the Transistor Article,
the Howto Guide, and Redlich. The MPEP, in relevant
part, § 2648 states:
    [N]o petition may be filed requesting review of a
    decision granting a request for reexamination
    even if the decision grants the request as to a spe-
    cific claim for reasons other than those advanced
    by the third party requester. No right to review
    exists as to that claim, because it will be reexam-
    ined in view of all prior art during the reexamina-
    tion under 37 CFR 1.937.
But that provision does not discuss the preclusive effect of
a determination that an issue does not raise a substantial
BELKIN INTL   v. KAPPOS                                   10


new question of patentability. Instead, MPEP § 2648
states the uncontroversial proposition that no petition
may be filed to review a decision granting a request for
reexamination. Id. The second clause of that sentence
adds that the situation is the same whether the Director
grants a request for reexamination for reasons other than
those advanced by the requester or not. Id. That is not
the situation here because reexamination was ordered
based on the requester’s proposed Peirce rejection. Even
so, the MPEP does not have the force of law, and is only
entitled to judicial notice as the PTO’s official interpreta-
tion of statutes and regulations with which it is not in
conflict. Molins PLC v. Textron, Inc., 48 F.3d 1172, 1180
n.10 (Fed. Cir. 1995).
    Belkin argues that 37 C.F.R. § 1.104 supports its in-
terpretation because that regulation requires the exam-
iner to make a “thorough investigation of the available
prior art” during reexamination. Regulation 1.104 does
not benefit Belkin, as the “available prior art” cited by the
regulation is only that which the Director has indicated
constitutes a substantial new question of patentability.
Thus, the fact that § 1.104 states that the examiner shall
make a thorough investigation of available prior art does
not affect the analysis. In any event, in order to reconcile
what may otherwise appear to be conflicting provisions,
we hold that, under the statute, available prior art may
only be considered to answer the specific questions of
patentability found by the Director. 2
    A casual reference to “all prior art” in the MPEP or
the regulations cannot be interpreted to trump the statu-



    2 We do not reach the issue of what prior art refer-
ences the PTO may or may not consider during reexami-
nation in response to an amended or substituted claim.
11                                     BELKIN INTL   v. KAPPOS


tory command. Statutes rank higher than regulations,
which rank higher than the MPEP.
    Belkin relies on a decision of the Director denying a
petition for review of the denial of four substantial new
questions of patentability relating to a different patent to
assert that it could not have petitioned the Director
concerning his decision on the substantial question of
patentability.    Decision Expunging Petitions, In re
Schwindt, Reexamination Control No. 95/001,743 (Mar. 5,
2012) (J.A. 1840–43). Belkin notes that the decision
denied the petition because reexamination was ordered
for the same claims on a different ground than proposed
by the requester pursuant to MPEP § 2648, similar to the
situation here. However inconsistent that decision may or
may not be with the Director’s current position, it must
yield to the statute, which denies appealability of the
Director’s decisions on substantial questions.
    Finally, Belkin raises concerns regarding estoppel.
Pursuant to 35 U.S.C. § 315(c), a third-party requester in
an inter partes reexamination is estopped from later
asserting the invalidity of any claim “finally determined
to be valid and patentable on any ground which the third-
party requester raised or could have raised” during the
reexamination. Id. Belkin argues that once reexamina-
tion has been granted, the requester must put forward all
eligible prior art or face that estoppel. Belkin’s concerns
are unwarranted.
    The question whether or not the estoppel statute
works to preclude citation of a piece of prior art that a
requester cited to the PTO, but that the Director deter-
mined did not raise a substantial new question of pat-
entability, is not before us. Suffice it to say here that the
courts have the final say on unpatentability of claims, not
the PTO. The Director’s determination that an issue does
BELKIN INTL   v. KAPPOS                                12


not raise a substantial new question is not a final deter-
mination of validity or patentability. As Belkin merely
asserted that the three references raised substantial new
questions of patentability as to claims 1-3 and 8-10—
which the Director rejected—Belkin’s arguments regard-
ing estoppel are thus not persuasive.
                          CONCLUSION
     We have considered Belkin’s remaining arguments
and conclude that they are without merit. The proper
course of action was for Belkin to have petitioned the
Director to review the determination that the arguments
relying on the Transistor Article, the Howto Guide, and
Redlich did not raise a substantial new question of pat-
entability pursuant to 37 C.F.C. § 1.927. Belkin did not
do so, and thus that decision became final and non-
appealable, rendering those issues beyond the scope of the
reexamination.    Accordingly, the Board’s decision is
affirmed.
                          AFFIRMED
