        NOTE: This disposition is nonprecedential

  United States Court of Appeals
      for the Federal Circuit
              __________________________

                 (Serial No. 10/667,216)
             IN RE SHAKER A. MOUSA
              __________________________

                      2011-1294
              __________________________

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

                Decided: April 19, 2012
              ___________________________

   JACK P. FRIEDMAN, Schmeiser, Olsen & Watts LLP, of
Latham, New York, for appellant.

    RAYMOND T. CHEN, Solicitor, Office of the Solicitor,
United States Patent and Trademark Office, of Alexan-
dria, Virginia, for appellee. With him on the brief were
KRISTI L.R. SAWERT and LYNNE E. PETTIGREW, Associate
Solicitors. Of counsel was JANET A. GONGOLA, Associate
Solicitor.
                __________________________

   Before PROST, SCHALL, and REYNA, Circuit Judges.
IN RE MOUSA                                              2


REYNA, Circuit Judge.
     This matter comes before the court on appeal from a
final decision of the United States Board of Patent Ap-
peals and Interferences (“BPAI”) sustaining the invalidity
of U.S. Patent Application No. 10/667,216 (“’216 applica-
tion”) for anticipation and obviousness. Because substan-
tial evidence supports the BPAI’s determination, we
affirm.
                        BACKGROUND
                   I.   The Technology
    Heparin is a drug that is typically used as a blood
thinner, or anticoagulant, to prevent blood clots from
forming. Heparin is less commonly used to prevent new
blood vessel growth in cancerous tissue. Heparin controls
this growth, known as angiogenesis, by blocking an en-
zyme, fibroblast growth factor (“FGF2”), that induces
blood vessel growth in tumors. Heparin’s use as a treat-
ment for angiogenesis is limited because its anticoagulant
properties cause bleeding complications.
    On a molecular level, heparin is a long-chain carbohy-
drate molecule consisting of repeating disaccharide units
with, inter alia, hydroxyl (-OH), carboxylated hydroxyl
(-OCOO-), and sulfated hydroxyl (-OSO3-) groups. This
molecule can be chemically fractured into smaller seg-
ments, called heparin fractions, which retain the antico-
agulant and angiogenesis properties of heparin.
                 II. The ’216 Application
   The ’216 application discloses super-sulfated, oxidized
heparin fractions (“’216 heparin fractions”), which are
produced by oxidizing some of the hydroxyl groups on the
heparin fraction and by substituting sulfate groups for the
hydrogen atoms in other hydroxyl groups. The ’216
3                                              IN RE MOUSA



application does not define the term “super-sulfated,” but
instead discloses that the ’216 heparin fraction has a high
ratio of sulfate (-SO3-) groups to carboxylate (-COO-)
groups, which can range from 2:1 to 5:1.
    According to the ’216 application, the increased oxida-
tion of the ’216 heparin fractions fully inhibits FGF2-
induced angiogenesis. Additionally, the bleeding compli-
cations normally associated with heparin use can be
eliminated by using these super-sulfated, oxidized hepa-
rin fractions, because they possess weaker anticoagulant
properties than heparin.
                    III. The Prior Art
    U.S. Patent No. 4,727,063 (“Naggi patent”), which is-
sued on February 23, 1988, discloses a super-sulfated
heparin fraction with weak anticoagulant properties. The
Naggi patent teaches treating heparin with a mixture of
sulfuric acid and chlorosulfonic acid, chemicals that are
strong oxidizing agents, to produce super-sulfated heparin
fractions (“Naggi heparin fractions”).
               IV. The Prosecution History
     On September 19, 2003, Appellant Shaker A. Mousa
filed the ’216 application for a patent claiming “oxidized
heparin fractions and their use in inhibiting angiogenesis”
with the United States Patent and Trademark Office
(“PTO”). In a final office action dated April 9, 2008, the
Examiner rejected claims 1, 2, 5, 6, 43, and 91-94 as
anticipated under 35 U.S.C. § 102(b) by the Naggi patent
and claims 1, 43, 49-54, 56-59, 61, and 62 as obvious
under 35 U.S.C. § 103(a) in view of the Naggi patent in
combination with other prior art. The Examiner found
that the Naggi heparin fractions were inherently oxidized
because the Naggi patent teaches treating heparin with
oxidizing agents and that the resulting structure was
IN RE MOUSA                                               4


identical to the ’216 heparin fractions. Further, the
Examiner found that the weak anticoagulant activity of
the Naggi heparin fractions indicated that the Naggi
heparin fractions inherently possess the anti-angiogenesis
properties of the ’216 heparin fractions.
    Mousa filed a Request for Continued Examination
(“RCE”) on August 11, 2008, and amended the claims to
include the limitation that the super-sulfated, oxidized
heparin fraction “fully inhibits fibroblast growth factor
(FGF2) induced angiogenesis,” where the underlined
portion is germane to this appeal. Mousa argued that this
limitation distinguished the Naggi patent from the ’216
application because the ’216 application does not claim all
super-sulfated, oxidized heparin fractions that may exist -
only those that fully inhibit FGF2-induced angiogenesis.
Mousa further argued that the Naggi patent does not
teach or suggest full inhibition of the FGF2 factor and,
thus, does not anticipate the ’216 application.
    The Examiner issued a non-final rejection of the ’216
application on October 27, 2008, which maintained the
rejections of the claims at issue as made in the previous
final office action of April 9, 2008, for anticipation or
obviousness in light of the Naggi patent. The Examiner
found that the Naggi patent discloses treating heparin
with sulfuric acid and chlorosulfonic acid, a strong oxidiz-
ing agent, which would fragment the heparin molecule
into fractions and would result in a super-sulfated hepa-
rin. The Examiner stated that this reaction would neces-
sarily encompass the reaction sequence of oxidizing said
heparin and then performing sulfate substitution at the
oxygen bonds within the depolymerized heparin. Further,
the Examiner found that the Naggi heparin fractions
possess a reduced anticoagulation reduction characteristic
as shown by the activated partial thromboplastin time
(“APTT”) and Heparin Antifactor Xa Assay (“Anti-Xa”)
5                                               IN RE MOUSA



results are disclosed in the Naggi patent. The Examiner
found that the APTT and Anti-Xa results indicated that
the Naggi heparin fractions inherently possess the angio-
genesis and anticoagulant characteristics claimed by
Mousa in the ’216 application.
    Independent claim 1 is representative of the rejected
claims. 1 It provides:
          1.   An oxidized heparin fraction having a
    molecular weight of from about 2,000 to about
    4,000 daltons,
        wherein the oxidized heparin fraction is su-
    per-sulfated such that the super-sulfated oxidized
    heparin fraction comprises an anticoagulant re-
    duction characteristic and an angiogenesis inhibi-
    tion characteristic;
        wherein the super-sulfated oxidized heparin
    fraction has a chemical structure of a first oxidized
    heparin fraction after the first oxidized heparin
    fraction has been O-sulfated by sulfate substitution


    1   The parties also treat dependent claims 93 and 94
as representative. Claim 93 explains the anticoagulant
reduction and angiogenesis inhibition characteristics
recited in claim 1 and identifies specific techniques that
can be used to determine these characteristics. Claim 94
is a product-by-process claim that recites a method for
creating the ’216 heparin fraction wherein the heparin
fraction is first oxidized and then O-sulfated via sulfate
substitution at the oxygen bonds. Although claims 93 and
94 are treated separately by the BPAI and the parties,
Mousa’s arguments and the Board’s findings address the
same claim language and the same portions of the Naggi
patent. Because claim 1 is representative of all the re-
jected claims, we do not address them separately given
that our review applies equally to all of the rejected
claims at issue in this appeal.
IN RE MOUSA                                              6


   at oxygen bonds within repeating units of the first
   oxidized heparin fraction;
       wherein the super-sulfated oxidized heparin
   fraction fully inhibits fibroblast growth factor
   (FGF2) induced angiogenesis.
(emphasis added).
                V.   The BPAI’s Decision
     Mousa appealed the Examiner’s non-final rejection to
the BPAI on February 27, 2009, arguing that the method
the Naggi patent uses to produce heparin fractions would
not result in super-sulfated, oxidized heparin fractions
with a chemical structure that is the same as that of the
’216 heparin fractions because Naggi merely treats hepa-
rin with oxidizing agents while Mousa teaches O-sulfating
a first oxidized heparin fraction. Mousa also argued that
the Naggi patent does not teach a heparin fraction which
fully inhibits FGF2 induced angiogenesis, a limitation
that is required by the ’216 claims. Mousa contended that
without experimental proof that the Naggi heparin frac-
tion could fully inhibit angiogenesis, the Naggi patent
could not anticipate the ’216 application.
    On appeal, the Examiner maintained that the Naggi
patent teaches a method that inherently oxidizes the
Naggi heparin fractions. Further, the Examiner main-
tained that the results of the APTT and Anti-Xa experi-
ments disclosed in the Naggi patent showed that the
Naggi heparin fractions possess a weak anticoagulant
property. The Examiner argued that this weak antico-
agulant property was the same as the property claimed by
Mousa and that this indicated that the Naggi heparin
fractions also inherently possess the anti-angiogenesis
properties claimed by the ’216 application.
7                                               IN RE MOUSA



    The BPAI affirmed the rejection of the claims. The
BPAI found that the Naggi patent discloses, inherently or
expressly, each and every limitation of the claims at issue
in the ’216 application. According to the BPAI, the Naggi
patent teaches super-sulfated heparin fractions with a
molecular weight between 3000 and 5000 daltons, a
sulfate to carboxylate ratio of 2.5, and a weak anticoagu-
lant reduction characteristic as compared to heparin.
Further, the BPAI found that the Naggi patent inherently
teaches an oxidized heparin fraction because it treats
heparin with sulfuric and chlorosulfonic acids, strong
oxidizing agents.
    Based on these findings, the BPAI concluded that the
Examiner had established that the heparin fractions
taught by the Naggi patent and the ’216 application were
“the same or substantially the same.” The BPAI held that
Naggi heparin fraction inherently possesses the anti-
angiogenesis characteristic required by claim 1 of the ’216
application. The BPAI then found that the Examiner had
properly shifted the burden of proof to Mousa to show that
the Naggi heparin fraction does not inherently possess the
anti-angiogenesis characteristics recited in claim 1 of the
’216 application. 2 Because claim 1 is representative of all
claims on appeal, Mousa bore the burden of proving that
none of the characteristics claimed by the ’216 application
were inherent to the Naggi heparin fraction.
    The BPAI went on to find claims 1, 43, 49-54, 56-59,
61, and 62 obvious under 35 U.S.C. § 103(a) in view of the
Naggi patent in combination with other prior art. While
the BPAI addressed each prior art reference relied upon


    2   In addition to claims 1, 93 and 94, the BPAI ad-
dressed claims 91, 92, and 43 as representative of the
anticipated claims. As these claims were not raised by
the parties on appeal, we do not address them.
IN RE MOUSA                                              8


by the Examiner in its decision, on appeal, Mousa argues
that the BPAI and Examiner failed to invoke the prior art
other than the Naggi patent in making this determination
and relies solely on his argument that the Naggi patent
does not anticipate.
    The BPAI affirmed the Examiner’s rejection of all the
claims at issue and denied a subsequent request for
rehearing. This appeal followed. We have jurisdiction
pursuant to 28 U.S.C. § 1295(a)(4)(A).
                       DISCUSSION
                 I.   Standard of Review
    Anticipation is a question of fact that this court re-
views for substantial evidence. See In re Aoyama, 656
F.3d 1293, 1296 (Fed. Cir. 2011); See Falko-Gunter
Falkner v. Inglis, 448 F.3d 1357, 1363 (Fed. Cir. 2006).
“[T]he possibility of drawing two inconsistent conclusions
from the evidence does not prevent an administrative
agency's finding from being supported by substantial
evidence.” Crash Dummy Movie, LLC v. Mattel, Inc., 601
F.3d 1387, 1390 (Fed. Cir. 2010) (quoting Consolo v. Fed.
Maritime Comm’n, 383 U.S. 607, 620 (1966)). Obvious-
ness is a question of law that this court reviews de novo.
In re Klein, 647 F.3d 1343, 1347 (Fed. Cir. 2011). The
BPAI’s factual findings underlying a determination of
obviousness are reviewed for substantial evidence. Id.
        II. Anticipation of the Claims on Appeal
    Anticipation of a claim under 35 U.S.C. § 102 occurs
when each claimed element and the claimed arrangement
or combination of those elements is disclosed, inherently
or expressly, by a single prior art reference. Therasense,
Inc. v. Becton, Dickinson & Co., 593 F.3d 1325, 1332 (Fed.
Cir. 2010). A reference inherently discloses an element of
a claim “if that missing characteristic is necessarily pre-
9                                               IN RE MOUSA



sent, or inherent, in the single anticipating reference.”
Schering Corp. v. Geneva Pharms., 339 F.3d 1373, 1377
(Fed. Cir. 2003) (citation omitted) (emphasis added).
“Inherency, however, may not be established by probabili-
ties or possibilities. The mere fact that a certain thing
may result from a given set of circumstances is not suffi-
cient.” Therasense, 593 F.3d at 1332 (citing Cont'l Can
Co. USA, Inc. v. Monsanto Co., 948 F.2d 1264, 1269 (Fed.
Cir. 1991)). The Examiner has the burden of providing
reasonable proof that a claim limitation is an inherent
characteristic of the prior art. In re Best, 562 F.2d 1252,
1254-55 (C.C.P.A. 1977); see also Crown Operations Int’l,
LTD v. Solutia Inc., 289 F.3d 1367, 1377 (Fed. Cir. 2002).
The Examiner meets this “burden of production by ‘ade-
quately explaining the shortcomings it perceives so that
the applicant is properly notified and able to respond.’” In
re Jung, 637 F.3d 1356, 1362 (Fed. Cir. 2011) (quoting
Hyatt v. Dudas, 492 F.3d 1365, 1370 (Fed. Cir. 2007)).
The burden of proof then shifts to the applicant “to prove
that the subject matter shown to be in the prior art does
not possess the characteristic relied on.” Best, 562 F.2d at
1254-55; In re Schreiber, 128 F.3d 1473, 1478 (Fed. Cir.
1997) (holding that once the Examiner established a
prima facie case of anticipation, the burden of proof was
properly shifted to the inventor to rebut the finding of
inherency).
    Here, the BPAI held that the Naggi patent expressly
or inherently discloses each and every limitation of claims
1, 2, 4, 5, 43, and 91-94 of the ’216 application. According
to the BPAI, the Naggi patent inherently discloses oxi-
dized, super-sulfated heparin fractions that are “the same
or substantially the same compound” as the ’216 heparin
fractions.
   On appeal, Mousa argues that the Naggi patent does
not disclose “a chemical structure of a first oxidized
IN RE MOUSA                                             10


heparin fraction” nor the claimed characteristic of a
heparin fraction that “fully inhibits fibroblast growth
factor (FGF2) induced angiogenesis.” The PTO counters
that the Examiner established that treating heparin with
the strong oxidizing agents taught in the Naggi patent
necessarily results in oxidized heparin and that the
Examiner appropriately shifted the burden of proof to
Mousa to show that those oxidizing agents did not oxidize
heparin. The PTO also argues that once the Examiner
demonstrated that the structures of the two heparin
fractions were identical, the burden of proof shifted to
Mousa to show that the Naggi heparin fractions did not
possess the same FGF2-inhibiting characteristics as the
’216 heparin fractions.
    We agree with the BPAI. “[W]hen the PTO shows
sound basis for believing that the products of the appli-
cant and the prior art are the same, the applicant has the
burden of showing that they are not.” In re Spada, 911
F.2d 705, 708 (Fed. Cir. 1990) (citations omitted). The
BPAI noted that the ’216 application teaches treating
heparin with oxidizing agents 3 but places no limitation on
which oxidizing agents may be used. The BPAI also noted
that the Naggi patent discloses treating heparin with
sulfuric acid and chlorosulfonic acid, chemicals that the
Examiner stated are known to be strong oxidizing agents.
These findings, along with the weak anticoagulant prop-
erties of the Naggi heparin fraction, are substantial
evidence that support the BPAI’s finding that the Naggi
patent teaches a super-sulfated, oxidized heparin fraction
identical to the ’216 heparin fraction.

   3    The ’216 application lists oxidizing agents as “in-
cluding, but not limited to, periodic acid, metals in high
valence states, halogens, halogen atoms, and compounds
with O-O bonds, such as O3, diacyl peroxides, H2O2, and
O2.”
11                                              IN RE MOUSA



     Having established that the two heparin fractions are
“the same or substantially the same compound” and that
the Naggi fractions necessarily possessed the FGF2-
inhibiting characteristic recited in claim 1, the Examiner
properly shifted the burden of proof to Mousa to prove
that the structures were different and that the claimed
properties were not inherent. The fairness of this shifting
“is evidenced by the PTO's inability to manufacture
products or to obtain and compare prior art products.”
Best, 562 F.2d at 1255 (“Where, as here, the claimed and
prior art products are identical or substantially identical .
. . the PTO can require an applicant to prove that the
prior art products do not necessarily or inherently possess
the characteristics of his claimed product.”). 4 Mousa
failed to satisfy this burden. Although Mousa argues that
oxidizing agents do not oxidize every substance and that
the Examiner did not establish that these chemicals can
oxidize heparin, Mousa provided no proof in support of
this contention to the Examiner or to the BPAI. “Appel-
lant’s unsupported statements . . . are not sufficient
evidence to rebut the examiner’s contention.” In re Hoke,
560 F.2d 436, 438 (C.C.P.A. 1977).
    Furthermore, once the Examiner established that the
Naggi patent read identically on the limitations of the
’216 claims, Mousa bore the burden to show that the
Naggi heparin fractions did not inherently possess the
FGF2-inhibiting characteristics of the ’216 heparin frac-
    4  Mousa contends that this court created a new and
more stringent standard in Spada, 911 F.2d at 708, that
requires the “virtual identity” of compounds to establish
inherency. Mousa argues that this standard overrules the
requirement of “identical or substantially identical”
compounds established by Best. 562 F.2d at 1255. We
disagree. The standard applied in Spada is consistent
with that articulated and applied in Best.
IN RE MOUSA                                              12


tions as recited by claim 1. Best, 562 F.2d at 1255.
Mousa again failed to satisfy his burden of proof. 5
    In affirming the rejection of the claims in the ’216 ap-
plication, the BPAI addressed the factual bases for the
findings of inherency and anticipation based on the Naggi
patent. Because we find that the BPAI’s factual findings
are supported by substantial evidence, we affirm the
BPAI’s decision.
    In light of this holding, we need not analyze the issue
of obviousness separately. The Examiner rejected inde-
pendent claims 1 and 43 as being both anticipated under
35 U.S.C. § 102 and obvious under 35 U.S.C. § 103(a).
The Examiner also rejected dependent claims 49-54, 56-
59, 61 and 62 as obvious based on Naggi and certain other
references. Mousa challenges the obviousness rejections
of the dependent claims solely on the ground that the
prior art does not disclose the limitations of claims 1 and
43 from which claims 49-54, 56-59, 61 and 62 depend. As
discussed above, the BPAI’s factual findings that the
Naggi patent anticipates the claims at issue in this appeal
are supported by substantial evidence. As we hold that
the Board did not err in finding that Naggi anticipates
claims 1 and 43 and thus discloses every limitation of
those claims, Mousa’s challenge to the obviousness rejec-
tions of claims 49-54, 56-59, 61 and 62 also fails.
                       CONCLUSION
   For the foregoing reasons, we affirm.
                       AFFIRMED

   5    Although Mousa presents other arguments re-
lated to the Examiner’s review of prior art, the BPAI
noted that the prior art was not properly before the Ex-
aminer and that the BPAI could therefore not consider
the prior art. We agree.
13                                     IN RE MOUSA



                          COSTS
Each party shall bear its own costs.
