Court Opinion

ID: 3180726
Source: CourtListenerOpinion
Date Created: 2016-02-26 16:06:42.418573+00
Date Added: 2024-06-11T14:34:38.439395
License: Public Domain

NOTE: This disposition is nonprecedential.

  United States Court of Appeals
      for the Federal Circuit
                ______________________

         HOWMEDICA OSTEONICS CORP.,
                 Appellant

                           v.

                   ZIMMER, INC.,
                    Cross-Appellant
                ______________________

                 2015-1498, 2015-1503
                ______________________

    Appeals from the United States Patent and Trade-
mark Office, Patent Trial and Appeal Board in No.
95/000,428.
                ______________________

              Decided: February 26, 2016
               ______________________

    TIMOTHY J. MALLOY, McAndrews, Held & Malloy,
Ltd., Chicago, IL, argued for appellant. Also represented
by PATRICIA J. MCGRATH, CHRISTOPHER M. SCHARFF.

    DAVID K. CALLAHAN, Latham & Watkins LLP, Chica-
go, IL, argued for cross-appellant. Also represented by
BRYAN SCOTT HALES, BRYAN RUTSCH, Kirkland & Ellis
LLP, Chicago, IL.
                ______________________
2                 HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.

    Before NEWMAN, LOURIE, and BRYSON, Circuit Judges.
     Opinion for the court filed by Circuit Judge LOURIE.
    Opinion concurring in part, dissenting in part filed by
                  Circuit Judge NEWMAN.
LOURIE, Circuit Judge.
    Howmedica Osteonics Corp. (“Howmedica”) appeals
from an inter partes reexamination decision of the United
States Patent and Trademark Office (“PTO”) Patent Trial
and Appeal Board (“the Board”) affirming the examiner’s
rejection of claims 1–6 of U.S. Patent 6,818,020 (“the ʼ020
patent”) as anticipated. See Smith & Nephew, Inc. v.
Howmedica Osteonics Corp., No. 2013-007710, 2014 WL
1729260, at *12 (P.T.A.B. Apr. 30, 2014) (“Decision”).
Zimmer, Inc. (“Zimmer”) cross-appeals from the Board’s
decision reversing the examiner’s rejection of claims 7–12
of the ʼ020 patent as obvious. Id. at *16. For the reasons
that follow, we affirm in part and reverse in part.
                        BACKGROUND
    Howmedica owns by assignment the ʼ020 patent (now
expired), directed to ultra-high molecular weight polyeth-
ylene (“UHMWPE”) with improved properties for use in
medical implants. UHMWPE is widely used in biomedi-
cal applications, and for “articulation surfaces in artificial
knee and hip replacements” in particular. ʼ020 patent col.
1 ll. 28–29. The ʼ020 patent explains that all implant
components go through a sterilization process, most often
irradiation, before use. Id. col. 1 ll. 42–56. One conse-
quence of that irradiation, however, is the generation of
free radicals. Id. col. 1 ll. 57–59.
     Free radicals are highly reactive and, when exposed to
air, can effect “oxidative chain scission reactions.” Id. col.
2 ll. 35–36. Through those oxidative reactions, the “mate-
rial properties of the [implant], such as molecular weight,
tensile, and wear properties, are degraded.” Id. col. 2 ll.
HOWMEDICA OSTEONICS CORP.     v. ZIMMER, INC.                3

36–38. If, however, irradiation occurs in an inert envi-
ronment, the free radicals react with each other to form
carbon-carbon cross-links. Id. col. 2 ll. 50–54. Such cross-
linking decreases the implant’s overall degradation.
     The ʼ020 patent describes a method for “providing a
polymeric material, such as UHMWPE, with superior
oxidative resistance upon irradiation,” and thereby gener-
ating UHMWPE implants with improved material proper-
ties. Id. col. 3 ll. 35–37. In particular, the ʼ020 patent
sets forth a two-step process, whereby the polymer is first
irradiated and then heat treated. Both steps take place in
an “oxidant-free atmosphere” to improve the cross-linking
of free radicals. Id. col. 3 l. 65–col. 4 l. 4. The ʼ020 patent
further provides that “the implant is heated for at least 48
hours at a temperature of about 37°C to about 70°C and
preferably for 144 hours at 50°C.” Id. col. 4 ll. 35–37 (the
preferred embodiment is further described as Method D,
’020 patent col. 7 ll. 51–58, the method Howmedica states
generates the claimed properties, Appellant’s Br. 5).
   Claims 1–12 of the ʼ020 patent all recite “[a] medical
implant comprising an irradiated [UHMWPE] having a
weight average molecular weight greater than 400,000,”
and at least one of the following properties:
    (1) a solubility of less than 80.9% in trichloroben-
        zene (claims 1–4, 7–9, and 12), and more par-
        ticularly in 1,2,4-trichlorobenzene (claim 5);
    (2) the level of free radicals at 1x1017 spins/gram
        or less (claims 2, 6, and 10);
    (3) a Fourier Transform Infrared Spectroscopy
        (“FTIR”) oxidation index that does not increase
        during oven aging in air at 80°C for up to 11
        days (claims 3, 7, and 9), 11 days (claims 6, 10,
        11, and 12), or up to 23 days (claims 4 and 8);
    (4) an FTIR oxidation index of 0.01 (claim 11) or
        less (claim 12); and/or
4                HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.

    (5) a weight percent of polyethylene with a molec-
        ular weight below 100,000 of less than 18.4%
        (claim 9).
Id. col. 12 ll. 1–54. Claims 7–12 further require the
UHMWPE to be “annealed at a temperature greater than
25°C for a sufficient time” to achieve one or more of the
above properties. Id. col. 12 ll. 24–54.
     In 2005, Howmedica sued Zimmer in the U.S. District
Court for the District of New Jersey, alleging infringe-
ment of claims 1–3, 5–7, and 10–12 of the ʼ020 patent, as
well as the claims of three related patents. 1 Howmedica
Osteonics Corp. v. Zimmer, Inc., Civ. No 05-897, 2008 WL
3871733, at *1 (D.N.J. Aug. 19, 2008). In 2007, the dis-
trict court issued its Markman Order, construing various
disputed terms. Id. Notably, it construed “annealed at a
temperature greater than 25°C” to mean “annealed at a
temperature greater than 25°C and less than the melting
point of the material—approximately 140°C.” Id. at *2.
In light of that construction, Zimmer moved for partial
summary judgment of noninfringement of claims 7, 10,
11, and 12 of the ʼ020 patent. Id. at *1. The court grant-
ed the motion, concluding that Zimmer’s accused products
were annealed above the melting temperature, i.e., at or
about 150°C, and thus did not satisfy the limitation as
construed, either literally or under the doctrine of equiva-
lents. Id. at *7 (“Absolutely distilled, Plaintiff’s argument
is: ignore the specific language and meaning of the claim

    1   In 2006, Zimmer moved for summary judgment
with respect to the three related patents. The district
court granted the motion in part, concluding that the
claims of the three related patents were invalid as indefi-
nite. Howmedica Osteonics Corp. v. Zimmer, Inc., Civ.
No. 05-897, 2007 WL 1741763 (D.N.J. June 13, 2007). We
affirmed without opinion in 2010. Howmedica Osteonics
Corp. v. Zimmer, Inc., 397 F. App’x 654 (Fed. Cir. 2010).
HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.              5

element. Unmelt is the same as melt. An antonym is a
synonym. Accordingly, the Court finds that there is no
genuine issue of material fact . . . .”).
    In 2009, Zimmer requested inter partes reexamination
of claims 1–12 of the ʼ020 patent. The PTO granted the
request, and the district court stayed its remaining pro-
ceedings pending the outcome of the reexamination.
     The examiner adopted many of Zimmer’s proposed
rejections, and rejected claims 1–12 over various prior art
references and combinations thereof. Joint App. (“J.A.”)
706–21. In particular, the examiner rejected claims 1–6
as inherently anticipated by Ching-Tai Lue, “Effects of
Gamma Irradiation and Post Heat Treatments on the
Structure and Mechanical Properties of Ultra High Mo-
lecular Weight Polyethylene (UHMWPE),” Masters The-
sis, University of Lowell, 1979 (“Lue”), as evidenced by
the declaration of Dr. Robert L. Clough (“Clough declara-
tion”). J.A. 710–12. The examiner also rejected claims 7–
12 as obvious over Lue in view of U.S. Patent 3,362,897
(“Lawton”). J.A. 715–16. Howmedica timely appealed to
the Board.
    The Board first affirmed the examiner’s rejection of
claims 1–6 as inherently anticipated by Lue as evidenced
by the Clough declaration. It noted that “[i]t is undisput-
ed that Lue describes UHMWPE that has been irradiated
in an inert atmosphere and heat treated at 150°C for one
hour. Lue does not[, however,] teach all the properties
recited in the claims.” Decision, 2014 WL 1729260, at *3.
The Board accordingly examined whether Lue’s material
inherently possesses the claimed properties, and found
that it does.
    Turning to the Clough declaration, the Board noted
that Dr. Clough testified to acquiring two different resins
of UHMWPE and followed a detailed protocol reproducing
the irradiation and heating procedures in Lue. Id. at *9.
Dr. Clough then measured the treated UHMWPE for
6                HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.

solubility, level of free radicals, and FTIR oxidation index,
closely following the testing procedures in the ʼ020 patent.
Id. Dr. Clough testified that the resulting measurements
fell within the ranges recited in the ʼ020 patent. Id. The
Board accordingly found that Zimmer had met its burden
of showing that the properties recited in the claims neces-
sarily were present in the UHMWPE samples treated as
described in Lue, and shifted the burden to Howmedica to
show otherwise. Id. at *12.
    The Board rejected each of Howmedica’s arguments in
response, finding (1) that the preamble language “medical
implant” did not limit claim scope, and (2) that Howmedi-
ca failed to show how any alleged difference between Dr.
Clough’s reproduction and either the procedure in Lue or
the solubility testing in the ’020 patent undermined Dr.
Clough’s demonstration that the claimed properties were
inherent in Lue. Id. at *10–12. In light of affirming the
examiner’s rejection of claims 1–6 as inherently anticipat-
ed by Lue as evidenced by the Clough declaration, the
Board declined to address the remaining rejections with
respect to those claims. Id. at *12.
    The Board then reversed the examiner’s rejections of
claims 7–12 as obvious in view of several prior art combi-
nations. Addressing the additional limitation in claims 7–
12—“annealed at a temperature greater than 25°C”—the
Board adopted the district court’s construction from the
parallel proceeding 2 and likewise interpreted the term to
require annealing “at a temperature greater than 25°C

    2   The ʼ020 patent expired during reexamination; the
Board accordingly reviewed the claims under the frame-
work set forth in Phillips v. AWH Corp., 415 F.3d 1303
(Fed. Cir. 2005) (en banc), and adopted the district court’s
interpretation of the “annealed at . . .” limitation. See In
re Rambus Inc., 694 F.3d 42, 46 (Fed. Cir. 2012).
HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.              7

and less than the melting point of the material, approxi-
mately 140°C.” Id. at *12–13.
     In light of that determination, the Board reversed the
examiner’s rejection of claims 7–12 as obvious over Lue in
view of Lawton. The Board first acknowledged that Lue
inherently discloses the claimed properties, but only by
annealing above the temperature range recited in the ’020
patent. Id. at *14. The Board then turned to Lawton for
guidance, finding that it indeed teaches annealing within
the claimed range, but nevertheless fails to suggest that
lowering the annealing temperature necessarily generates
the same properties for a given sample of UHMWPE. Id.
Accordingly, the Board found that “neither the Examiner
nor the Requester provided a basis in fact and/or technical
reasoning” to show why a skilled artisan would expect
modifying Lue in light of Lawton to generate UHMWPE
with the claimed properties. Id.; id. at *15 (“[T]he Exam-
iner and Requester have not shown that, more likely than
not, the skilled artisan would have recognized that the
particular required properties could be achieved at tem-
peratures below 140°C by optimizing these parameters.”).
The Board consequently reversed the examiner’s rejection
of claims 7–12 as obvious over Lue in view of Lawton. It
then found the examiner’s remaining rejections similarly
flawed, and reversed on those grounds as well. Id. at *15.
As a result, the Board declined to address the secondary
considerations of nonobviousness. Id. at *16.
    Howmedica requested rehearing but the Board reject-
ed the request. Howmedica timely appealed, and Zimmer
timely cross-appealed. We have jurisdiction pursuant to
28 U.S.C. § 1295(a)(4)(A).
                       DISCUSSION
                I.   Howmedica’s Appeal
    “Determining whether claims are anticipated is a two-
step analysis. The first step involves construction of the
8                HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.

claims of the patent at issue.” In re Aoyama, 656 F.3d
1293, 1296 (Fed. Cir. 2011). Whether a preamble limits a
claim is a question of claim construction. Catalina Mktg.
Int’l, Inc. v. Coolsavings.com, Inc., 289 F.3d 801, 808 (Fed.
Cir. 2002). In this case, because the intrinsic record fully
determines the proper construction, we review the Board’s
construction de novo. Microsoft Corp. v. Proxyconn Inc.,
789 F.3d 1292, 1297 (Fed. Cir. 2015) (citing Teva Pharm.
USA, Inc. v. Sandoz, Inc., 135 S. Ct. 831, 840–42 (2015)).
    “The second step involves comparing the claims to the
prior art.” In re Aoyama, 656 F.3d at 1296. A prior art
reference anticipates a claim if it discloses each and every
limitation. Schering Corp. v. Geneva Pharm., 339 F.3d
1373, 1377 (Fed. Cir. 2003). A single reference may also
anticipate without expressly disclosing a limitation of the
claimed invention, if that limitation is necessarily present,
or inherent, in the reference. See id. Indeed, the inherent
result must inevitably result from the disclosed steps; it
cannot be established by probabilities or possibilities. See
Bettcher Indus., Inc. v. Bunzl USA, Inc., 661 F.3d 629, 639
(Fed. Cir. 2011). Whether a reference anticipates is a
question of fact that we review for substantial evidence on
appeal. In re Morsa, 713 F.3d 104, 109 (Fed. Cir. 2013).
                              A.
    On appeal, Howmedica first faults the Board for find-
ing that the preamble, “medical implant,” does not limit
claim scope. 3 According to Howmedica, “medical implant”
permeates the specification and is an essential feature,
giving life, meaning, and vitality to the claims. Howmedi-
ca argues that this is relevant for two reasons: first, Lue
does not disclose medical implants, and therefore does not

    3   Claims 1–12 all contain the preamble, “medical
implant.” Howmedica challenges the Board’s determina-
tion only with respect to claims 1–6.
HOWMEDICA OSTEONICS CORP.     v. ZIMMER, INC.                9

anticipate; and second, Dr. Clough’s reproductions were
not prepared using medical grade UHMWPE, and thus
cannot establish inherent anticipation.
    Zimmer responds that the preamble language, “medi-
cal implant,” is not limiting. In particular, Zimmer con-
tends that the body of each claim defines a structurally
complete invention, and that the preamble offers no more
than a purpose or intended use for UHMWPE with the
claimed properties.
     “Whether to treat a preamble as a limitation is a de-
termination ‘resolved only on review of the entire[] . . .
patent to gain an understanding of what the inventors
actually invented and intended to encompass by the
claim.’” Catalina, 289 F.3d at 808 (quoting Corning Glass
Works v. Sumitomo Elec. U.S.A., Inc., 868 F.2d 1251, 1257
(Fed. Cir. 1989)). “[T]here is no simple test for determin-
ing when a preamble limits claim scope, [but] we have set
forth some general principles to guide that inquiry.” Am.
Med. Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1358 (Fed.
Cir. 2010). Generally, a preamble is not limiting. Allen
Eng’g Corp. v. Bartell Indus., Inc., 299 F.3d 1336, 1346
(Fed. Cir. 2002). But a preamble may limit the invention
if it recites essential structure or steps, or if it is “neces-
sary to give life, meaning, and vitality” to the claim. See
Pitney Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d 1298,
1305 (Fed. Cir. 1999). Conversely, a preamble does not
limit an invention “where a patentee defines a structural-
ly complete invention in the claim body and uses the
preamble only to state a purpose or intended use for the
invention.” Rowe v. Dror, 112 F.3d 473, 478 (Fed. Cir.
1997).
    In light of those principles, we agree with the Board
and conclude that the preamble, “medical implant,” does
not limit claim scope. The applicant did not rely on that
phrase to define the invention, cf. Rowe, 112 F.3d at 479
(noting that the use of Jepson format “suggests the struc-
10               HOWMEDICA OSTEONICS CORP.     v. ZIMMER, INC.

tural importance of the recitations found in the pream-
ble”), or to distinguish prior art during prosecution, J.A.
5469; see also Am. Med., 618 F.3d at 1359. Nor does any
term in the bodies of the claims rely on “medical implant”
for antecedent basis. Cf. Pitney Bowes, 182 F.3d at 1306
(finding the preamble “necessary to give life, meaning,
and vitality” to the claim because terms from the body of
the claim “c[ould] only be understood in the context of the
preamble statement”).
    On the contrary. The body of each claim describes a
structurally complete invention, e.g., ’020 patent col. 12 ll.
2–4 (“[A]n irradiated [UHMWPE] having a weight aver-
age molecular weight greater than 400,000 and a solubili-
ty of less than 80.9% in trichlorobenzene.”), and deletion
of the preamble language does not affect that structure,
Catalina, 289 F.3d at 808. The preamble merely de-
scribes a use or purpose for irradiated and heat treated
UHMWPE with the claimed properties. Rowe, 112 F.3d
at 478; Decision, 2014 WL 1729260, at *3 (finding that
“medical implant” “imports that a UHMWPE is suitable
as a medical implant if it has the claimed properties”).
The specification’s regular use of the preamble language,
“medical implant,” is of no additional import here; it
reiterates that a “medical implant” is one use for
UHMWPE with the claimed solubility, FTIR oxidation
index, and level of free radicals.
     Because we agree with the Board, and conclude that
the preamble language, “medical implant,” does not limit
the claims, we need not also address whether Lue teaches
medical implants or whether Dr. Clough’s reproductions
fail to use medical grade UHMWPE and thereby fail to
establish inherent anticipation.
                             B.
    Howmedica next challenges two aspects of the Board’s
finding that claims 1–6 of the ’020 patent are inherently
anticipated by Lue as evidenced by Clough’s declaration.
HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.              11

First, Howmedica argues that Dr. Clough did not faithful-
ly reproduce Lue, either in the UHMWPE resin used or in
the irradiation procedure. It contends that the deviations
at best show that the claimed properties might be present
in Lue, and thereby fail to establish a sound basis for the
Board to believe that Lue discloses the same product
claimed by the ’020 patent and to then shift the burden to
Howmedica to prove otherwise. We find this first chal-
lenge unpersuasive.
    Without question, “[i]nherency is a very tricky concept
in patent law.” In re Montgomery, 677 F.3d 1375, 1383
(Fed. Cir. 2010) (Lourie, J., dissenting). “An unbounded
concept of inherency . . . threatens to stymie innovation by
withdrawing from the realm of patentability that which
has not been before known, used, or benefited from.” Id.
at 1383–84. As a result, there are strict requirements
before a finding of inherent anticipation is made. Indeed,
inevitability is at the heart of inherency; “that a certain
thing may result from a given set of circumstances is not
sufficient.” In re Robertson, 169 F.3d 743, 745 (Fed. Cir.
1999) (citations and quotation marks omitted).
    “[W]hen the PTO shows sound basis for believing that
the products of the applicant 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).
Such a burden-shifting framework is fair because of “the
PTO’s inability to manufacture products or to obtain and
compare prior art products.” In re Best, 562 F.2d 1252,
1255 (CCPA 1977) (referencing In re Brown, 459 F.2d 531
(CCPA 1972)).
    The Board implemented that burden-shifting frame-
work in this case, and we find no error in its application.
With the principles of In re Spada and In re Best in mind,
the Board first analyzed the disclosure of Lue. See Deci-
sion, 2014 WL 1729260, at *3. It found that Lue discloses
irradiating and heat treating UHMWPE, but at a higher
12               HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.

temperature and for a shorter period of time than in the
’020 patent. Compare ’020 patent col. 4 ll. 35–37 (heating
preferably for 144 hours at 50°C), with Decision, 2014 WL
1729260, at *4 (stating Lue teaches heating for 1 hour at
150°C). According to the Board, the procedures were not,
on their face, similar enough such that the Board could
presume, without more, that Lue’s product was the same
as that in the ’020 patent. Decision, 2014 WL 1729260, at
*5. The Board thus turned to other evidence of record for
guidance. Id. at *6, *9.
     In particular, the Board turned to the Clough declara-
tion and found that it demonstrated that heat treating by
the procedures described in both Lue and the ’020 patent
generated UHMWPE with the same properties. Id. at *9,
*12. In reaching that determination, the Board analyzed
how faithfully Dr. Clough reproduced Lue’s procedure. It
first addressed the resin used by Lue, acknowledged that
Lue’s resin source no longer exists in its original form, but
nevertheless found that Dr. Clough “took reasonable steps
to find similar UHMWPE to that available at the time of
Lue.” Id. at *10. Indeed, as Dr. Clough testified:
     (1) Lue obtained UHMWPE from Dixon Corpora-
         tion’s (“Dixon”) Bristol, Rhode Island manufac-
         turing facility;
     (2) Dixon became St. Gobain Performance Plastics
         (“St. Gobain”);
     (3) Dr. Clough obtained two lots of GUR 4130 ma-
         terial from St. Gobain’s Bristol, Rhode Island
         facility, “which continues to manufacture
         UHMWPE under the trade name Pennlon ac-
         cording to the same process, using the same
         resin-grade, and equipment it has been using
         since the 1970’s”; and
     (4) Dr. Clough obtained one lot of GUR 4030,
         which was sent to St. Gobain “to be made into
HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.              13

       UHMWPE sheets using the same process and
       equipment they use to make Pennlon.”
J.A. 2049.
    The Board then addressed Dr. Clough’s application of
the procedures set forth in Lue. According to the Board,
Dr. Clough “prepared a detailed protocol for reproducing
the irradiation and heating procedures set forth in Lue on
GUR 4030 and GUR 4130 UHMWPE samples.” Decision,
2014 WL 1729260, at *9. Those tests demonstrated a
level of free radicals, solubility, and FTIR oxidation index
within the ranges recited in the claims of the ’020 patent.
J.A. 2050. The Board found Dr. Clough’s test results to be
the “most detailed data presented in the record.” Deci-
sion, 2014 WL 1729260, at *9.
    Howmedica argues that the Board accepted too many
deviations from the strict disclosure of Lue and that, with
findings clouded by such uncertainty, the Board lacked a
sound basis for believing that the products of Lue and the
’020 patent are the same.
    We disagree. A sound basis for believing in identity
does not turn on absolute certainty; rather, a sound basis
for finding identity requires the Board to make sufficient
factual findings, such that it can reasonably infer that the
prior art product and that of the patent at issue are the
same. See In re Spada, 911 F.2d at 708. The Board did
that here.
     With respect to the starting resin, the Board reasona-
bly found that Dr. Clough used a proper starting material.
As Howmedica contends, Dixon produced several types of
UHMWPE during the 1970s, including several blends. It
produced two resins, GUR 4030 and GUR 4130, J.A. 619–
20; J.A. 637–38, and used GUR 4130 as the base for each
of its blends, J.A. 641. Howmedica contends that with so
many types of UHMWPE to choose from, Lue’s disclosure
14               HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.

of Dixon products generally offers no guidance to a poten-
tial reproducer. We find that contention unpersuasive.
    First, any blend that Dixon produced is irrelevant, for
Lue suggests that he used unblended UHMWPE, compare
J.A. 124, with J.A. 126–27; thus, Dr. Clough used un-
blended UHMWPE. The only remaining concern involves
the use of GUR 4030 versus GUR 4130, and that distinc-
tion is of no moment here because Dr. Clough acquired
and used both. J.A. 2049. Moreover, all of his reproduc-
tions with both resins generated UHMWPE with the
claimed properties. J.A. 2050–51. That Dr. Clough
acquired his materials from Dixon’s successor certainly
adds an element of uncertainty. But that should not be
enough to foreclose the Board’s sound basis for believing
in identity, where, as here, Dr. Clough took reasonable
steps to acquire an appropriate starting material. We see
no error in the Board’s finding on this point.
    With respect to the irradiation procedure, we similar-
ly conclude that the Board reasonably found Dr. Clough’s
reproduction to align with the disclosure of Lue. Accord-
ing to Howmedica, Dr. Clough deviated from Lue’s irradi-
ation procedure in six respects, including using a different
dose rate and time. Appellant’s Br. 54–55. Importantly,
however, Howmedica does not assert that Dr. Clough
deviated in total dose. Indeed, Lue subjected test samples
to 2.5 Mrad of radiation, J.A. 126, and Dr. Clough com-
plied with that dosage, J.A. 2049. Dr. Clough’s remaining
deviations are of no consequence here. Minor deviations
from the strict disclosure of the prior art are accepted, as
long as one of skill in the art would understand that those
minor deviations are consistent with the prior art’s teach-
ings. See Glaxo Inc. v. Novopharm Ltd., 52 F.3d 1043,
1047 n.4 (Fed. Cir. 1995). Here, Lue suggests that total
radiation dose is the most relevant variable for the irradi-
ation procedure. J.A. 103. Indeed, Lue notes that neither
dose rate nor irradiation time affects the properties of the
final material. J.A. 103–104; J.A. 2142–43; J.A. 2159. Dr.
HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.              15

Clough complied with that prescription, and only deviated
in otherwise trivial respects. It was therefore reasonable
for the Board to find Dr. Clough’s testing to be an accu-
rate reproduction of Lue, and to accordingly place signifi-
cant weight on the results of those tests. 4 We see no error
in the Board’s finding on this point.
    Ultimately, the Board found Dr. Clough faithfully and
accurately reproduced Lue. The results of that reproduc-
tion demonstrated that UHMWPE treated according to
Lue has the same properties as those claimed in the ’020
patent. We conclude that, in view of such findings, the
Board had a sound basis for believing that the products of
the prior art and the patent at issue are the same. Thus,
the Board correctly shifted the burden to Howmedica to
prove otherwise.
    Howmedica next argues, in the alternative, that the
Board erred in concluding that Howmedica failed to show
otherwise. Specifically, Howmedica argues that it suffi-
ciently established that Dr. Clough’s failure to use a hot
wire mesh during solubility testing discredited his results,
undermining any finding that Lue’s product necessarily
has the solubility claimed in the ’020 patent. We find this
challenge similarly unpersuasive.
    The ’020 patent describes a method of testing solubili-
ty in trichlorobenzene as follows: “The samples were then
hot filtered at approximately 170°C using separate pre-

   4    Howmedica also argues that Zimmer should have
conducted additional testing of Dr. Clough’s product by,
for example, measuring xylene extraction and/or tensile
properties. Appellant’s Br. 57. While such testing could
have been useful, the Board nevertheless had ample
evidence before it to find that Dr. Clough accurately
reproduced Lue, generating UHMWPE with the claimed
properties.
16                HOWMEDICA OSTEONICS CORP.     v. ZIMMER, INC.

weighed high temperature filters for each sample.” ’020
patent col. 9 ll. 54–56. It does not specifically require the
use of a hot wire mesh. In view of that disclosure, the
Board found that Dr. Clough adequately tested for solubil-
ity. In particular, the Board found that Dr. Clough “used
a high temperature 400-mesh wire filter 0.0001 thick,”
placed “between two glass funnels, with the upper glass
funnel preheated to 170°C. The trichlorobenzene solution
(150 mL), which was also at 170°C, was then filtered.”
Decision, 2014 WL 1729260, at *11. The Board shifted
the burden accordingly for Howmedica to show that the
failure to use a hot wire mesh was significant. The Board
found that Howmedica failed to make such a showing,
and we conclude that substantial evidence supports that
finding.
     Howmedica presented expert reports of irradiated and
heat treated UHMWPE, subjected to solubility testing in
trichlorobenzene in three scenarios: hot filter/hot filtrate,
hot filter/cooled filtrate, and cold filter/cooled filtrate. Id.
The Board found that none of the reports contradicted Dr.
Clough’s test results. First, the Board found that no
evidence of record reflected the effects of systematic
cooling on Dr. Clough’s samples. Id. Indeed, Dr. Clough
testified to using filtrate at 170°C, and nothing suggested
that his filtrate dropped below 140°C. Thus, two of
Howmedica’s testing scenarios, those with a cooled fil-
trate, were inapposite. The last scenario similarly failed.
Id. As the Board found, the hot filter/hot filtrate scenario
did not show that filter temperature is a critical factor,
largely because it failed to replicate and compare the cold
filter/hot filtrate allegedly used by Dr. Clough. Id.
Howmedica does not raise any argument on appeal to
persuade us that the Board’s detailed factual findings
lack substantial evidence support. We therefore conclude
that the Board correctly found that Howmedica did not
meet its burden before the Board.
HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.              17

    In sum, the Board correctly applied the burden-
shifting framework of In re Spada and determined that
Howmedica failed to satisfy its burden before the Board.
We accordingly affirm the Board’s finding that claims 1–6
of the ’020 patent are inherently anticipated by Lue.
                II. Zimmer’s Cross-Appeal
    Whether claims would have been obvious is a legal de-
termination based on underlying factual findings. In re
Baxter, 678 F.3d 1357, 1361 (Fed. Cir. 2012). We review
the Board’s ultimate conclusion of obviousness de novo, In
re Elsner, 381 F.3d 1125, 1127 (Fed. Cir. 2004), and we
review the Board’s underlying factual findings for sub-
stantial evidence, In re Gartside, 203 F.3d 1305, 1316
(Fed. Cir. 2000). Whether there would have been a moti-
vation to combine references and a reasonable expectation
of success in doing so are such factual findings. See In re
Hyon, 679 F.3d 1363, 1365–66 (Fed. Cir. 2012); Wyers v.
Master Lock Co., 616 F.3d 1231, 1237–38 (Fed. Cir. 2010).
    Zimmer challenges the Board’s conclusion that claims
7–12 of the ’020 patent would not have been obvious over
the applied prior art. It raises two challenges, and we
address each in turn.
                            A.
     Zimmer first faults the Board for assigning patentable
weight to the additional limitation in claims 7–12, name-
ly, “annealed at a temperature greater than 25°C.” Ac-
cording to Zimmer, it is a process limitation in product-by-
process claims and thus plays no part in the patentability
analysis under In re Thorpe, 777 F.2d 695 (Fed. Cir. 1985)
(the “Thorpe issue”). Because claims 7–12 only differ from
claims 1–6 by the addition of that limitation, Zimmer
argues that claims 7–12 should also be found inherently
anticipated by Lue as evidenced by the Clough declara-
tion.
   Howmedica responds that Zimmer failed to properly
18               HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.

raise the Thorpe issue before the Board and has therefore
waived it. We agree.
     In an appeal from a Board decision, “we have before
us a comprehensive record that contains the arguments
and evidence presented by the parties”; our review of that
decision is limited to the “four corners” of that record. In
re Gartside, 203 F.3d 1305, 1314 (Fed. Cir. 2000). With-
out “the benefit of the Board’s informed judgment” in the
first instance, we decline to consider arguments not raised
before the Board. In re Watts, 354 F.3d 1362, 1369 (Fed.
Cir. 2004); In re Berger, 279 F.3d 975, 984 (Fed. Cir. 2002)
(declining to consider indefiniteness rejection not contest-
ed before the Board); In re Schreiber, 128 F.3d 1473, 1479
(Fed. Cir. 1997) (declining to consider whether prior art
cited in an obviousness rejection was analogous art when
that argument was not raised before the Board).
     Zimmer contends that it raised the Thorpe issue in its
request for reexamination and in its response brief before
the Board, but we agree with Howmedica that it did not.
At best, Zimmer suggested that Lue might anticipate
claims 7–12, but only if the limitation was broadly con-
strued to allow annealing at 150°C. Suggesting that Lue
anticipates in an entirely different context, i.e., where the
limitation bears patentable weight and warrants a specif-
ic construction, J.A. 1081; J.A. 2468 n.10, does not consti-
tute adequately raising the Thorpe issue. Zimmer’s brief
mention of the Thorpe issue for the first time during an
oral hearing before the Board, J.A. 2509; J.A. 2526, more-
over, does not remedy that shortcoming. Zimmer failed to
fully raise the Thorpe issue at any point during the pro-
ceedings before the PTO. We therefore find the Thorpe
issue waived and decline to consider it further.
                             B.
    Zimmer next argues that the Board erred in conclud-
ing that claims 7–12 of the ’020 patent would not have
been obvious over the cited references. Specifically, it
HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.              19

contends that a skilled artisan, with an understanding of
the Arrhenius equation, would have reasonably expected
decreasing the annealing temperature of Lue, according to
the teaching of Lawton, to still generate the same prod-
uct, i.e., irradiated UHMWPE with the properties recited
in the ’020 patent. We agree.
     Subsumed within an obviousness analysis “is a
subsidiary requirement” that when “all claim limitations
are found in a number of prior art references, the burden
falls on the challenger” to show that “a skilled artisan
would have been motivated to combine the teachings of
the prior art,” and that “a skilled artisan would have had
a reasonable expectation of success in doing so.” Pfizer,
Inc. v. Apotex, Inc., 480 F.3d 1348, 1361 (Fed. Cir. 2007).
“The expectation of success must be founded in the prior
art, not in the applicant’s disclosure.” In re Dow Chem.
Co., 837 F.2d 469, 473 (Fed. Cir. 1988). Absolute predict-
ability is not the standard; “all that is required is a rea-
sonable expectation” derived from the prior art or common
sense. In re Kubin, 561 F.3d 1351, 1360 (Fed. Cir. 2009)
(quoting In re O’Farrell, 853 F.2d 894, 903–04 (Fed. Cir.
1988)); see Amgen v. F. Hoffman La Roche Ltd., 580 F.3d
1340, 1362 (Fed. Cir. 2009) (“An obviousness determina-
tion requires that a skilled artisan would have perceived a
reasonable expectation of success in making the invention
in light of the prior art.”).
    Here, the Board only reversed the examiner’s conclu-
sion that claims 7–12 would have been obvious because it
found that a skilled artisan would not have expected to
achieve “the particular recited properties without hind-
sight reliance on the annealing times and temperatures”
in the ’020 patent. Decision, 2014 WL 1729260, at *15.
That finding is not supported by the record.
   This is a crowded art detailing a well-known problem
and solution: the annealing of irradiated polyethylene to
improve oxidation resistance. The ’020 patent has at-
20               HOWMEDICA OSTEONICS CORP.     v. ZIMMER, INC.

tempted to fit within that crowd by claiming specific
properties after annealing within a stated temperature
range. ’020 patent col. 12 ll. 24–54. As the Board found,
and as we affirmed above, Lue discloses those properties
when the annealing step occurs just outside of that stated
temperature range. The Board then assessed the remain-
ing art, finding that Lawton similarly discloses annealing
irradiated polyethylene, this time within the temperature
range described in the ’020 patent. Decision, 2014 WL
1729260, at *14. Indeed, the Board found that Lawton
not only embraces the well-known problem and solution,
but touts the further benefit that annealing just below the
melting point will “render [the product] substantially
amorphous without allowing [it] to lose its shape.” Id.
(citing Lawton col. 7 ll. 63–67). The Board found, howev-
er, that a skilled artisan would not have expected modify-
ing Lue according to Lawton, and thereby decreasing the
annealing step in Lue by at least 10°C, to yield the same
end product. Id.
    In coming to that conclusion, the Board did not note
the highly predictable nature of the technology. DePuy
Spine, Inc. v. Medtronic Sofamor Danek, Inc., 567 F.3d
1314, 1326 (Fed. Cir. 2009) (“[P]redictability is a touch-
stone of obviousness.”). As we have stated many times,
“[o]bviousness does not require absolute predictability of
success . . . all that is required is a reasonable expectation
of success.” In re Kubin, 561 F.3d at 1350. The record
here overwhelmingly suggests such a reasonable expecta-
tion of success.
    Throughout the proceedings, before the PTO and the
district court, both parties submitted evidence establish-
ing that polymer chemistry is governed by the well-known
Arrhenius equation. As even Howmedica’s expert stated:
“a heating time and a heating temperature are inversely
related. That is, according to the Arrhenius equation, an
increase in the heating temperature requires a lower
heating time to achieve the same or [a] similar reaction
HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.               21

time.” J.A. 2777; see ’020 patent col. 6 ll. 36–48 (even the
’020 patent embraces the “well-known Arrhenius equa-
tion”: “if a higher temperature is used, a short time period
is required to achieve a [specific] prescribed level of oxida-
tion resistance and cross-linking”). Thus, a skilled arti-
san, armed with that understanding, would appreciate
that a specific product can be generated by annealing at
any point along the temperature/time spectrum. Indeed,
Howmedica’s expert stated: “One of ordinary skill in the
art further understands that, by applying the Arrhenius
equation, a level of cross-linking in similarly irradiated
UHMWPE materials may be obtained by utilizing various
heating[] times and temperatures.” J.A. 2778.
    The Board avoided this well-known principle in its
analysis of inherent anticipation, see Decision, 2014 WL
1729260, at *4–5, and avoidance was justified in that
context.    But the Board cannot ignore that long-
established principle here, where it must give due defer-
ence to the understanding of those skilled in art, and
assess whether that skilled artisan would view prior art
references and expect their combination to successfully
achieve a particular result. We “cannot [now] deem
irrelevant the ease and predictability” of decreasing the
annealing temperature in Lue to achieve the below-the-
melting-point teaching of Lawton. In re Kubin, 561 F.3d
at 1360. The record overwhelmingly establishes that a
skilled artisan would understand that modifying the
annealing temperature of Lue, as set forth in Lawton,
would generate the same end-product, as long as the
annealing time was also modified. And Howmedica failed
to present any contrary evidence of unpredictability. The
Board’s brief reliance on the ’020 patent’s discussion of a
four-hour annealing minimum in the pre-irradiation
context, Decision, 2014 WL 1729260, at *14, does not
convince us otherwise.
   The Board’s finding that a skilled artisan would not
have reasonably expected that modifying Lue according to
22               HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.

Lawton would generate UHMWPE with the recited prop-
erties lacks substantial evidence support. Furthermore,
although Howmedica offers minimal indications of com-
mercial success to support the Board’s conclusion, those
indications fail to outweigh the otherwise clear indication
of obviousness apparent in the prior art. Ball Aerosol &
Specialty Container, Inc. v. Ltd. Brands, Inc., 555 F.3d
984, 994 (Fed. Cir. 2009) (citing Leapfrog Enters., Inc. v.
Fisher-Price, Inc., 485 F.3d 1157, 1162 (Fed. Cir. 2007)).
Accordingly, we reverse the Board’s determination, and
conclude that claims 7–12 would have been obvious over
Lue in view of Lawton.
                       CONCLUSION
    We have considered all remaining arguments, but
conclude that they are without merit. For the reasons set
forth above, we affirm the Board’s finding that claims 1–6
are invalid as inherently anticipated, and we reverse the
Board’s conclusion that claims 7–12 would not have been
obvious.
     AFFIRMED IN PART, REVERSED IN PART
                          COSTS
     No costs.
        NOTE: This disposition is nonprecedential.

  United States Court of Appeals
      for the Federal Circuit
                  ______________________

          HOWMEDICA OSTEONICS CORP.,
                  Appellant

                             v.

                     ZIMMER, INC.,
                      Cross-Appellant
                  ______________________

                   2015-1498, 2015-1503
                  ______________________

    Appeals from the United States Patent and Trade-
mark Office, Patent Trial and Appeal Board in No.
95/000,428.
                ______________________
NEWMAN, Circuit Judge, concurring in part and dissent-
ing in part.
    I concur in the judgment with respect to claims 1–6.
As to claims 7–12, I would sustain the judgment of the
PTO Board. Thus I respectfully dissent from the reversal
of the PTO’s judgment as to claims 7–12.
    Claims 1–6: Anticipation
    I agree that the Board correctly applied the law of in-
herent anticipation, and that the claims were appropri-
ately found to be invalid. I remark however, that the
Board erred in treating part of the claims’ recitation of the
2                HOWMEDICA OSTEONICS CORP.     v. ZIMMER, INC.

claimed subject matter as a “preamble”. Claims 1–12 all
commence as follows:
    A medical implant comprising an irradiated ultra-
    high molecular weight polyethylene [UHMWPE]
    having a weight average molecular weight greater
    than 400,000 and a solubility of less than 80.9% in
    trichlorobenzene.
    The Board held, and the panel majority agrees, that
the words “medical implant” are not a limitation of the
claim, but a mere “preamble” of no limitation effect. That
is incorrect. First, the claim is not written in preamble
form, but is explicitly directed to a medical implant, not to
a polymer of varied uses whereby the product identified in
the “preamble” may not be limiting of either validity or
infringement. For example, were the accused irradiated
polyethylene used as a street lamp, it would be ridiculous
for Howmedica to accuse that product of infringement of
these claims, even ere all of the listed properties identical.
The claims are limited to medical implants as much as
they are limited by the molecular weight and solubility.
    Thus I do not join the court’s ruling that “medical im-
plant” is not a claim limitation and is irrelevant to the
determination of anticipation. I do not share the court’s
theory that claims 1–12 apply to any polyethylene having
the physical and chemical characteristics stated in the
claim, no matter how remote the product is from being a
medical implant.
    However, that does not save claims 1–6 here, because
the Lue thesis mentions medical prosthetic uses of the
irradiated polyethylene. Lue states:
    Recently, UHMW-PE is also being used extensive-
    ly for prosthetic body implants. The low coeffi-
    cient of friction, high wear resistance, and
    toughness have brought UHMW-PE’s use in arti-
    ficial hips, fingers, knees, etc. Extensive evalua-
 HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.              3

    tion by engineering and medical professionals has
    indeed shown that the unique properties of
    UHMW-PE make it the best material available for
    these applications.
Ching-Tai Lue, Effects of Gamma Irradiation and Post
Heat Treatments on the Structure an Mechanical Proper-
ties of Ultra High Molecular Weight Polyethylene
(UHMW-PE) (June 1979) (M.S. thesis, University of
Lowell) at 52 (“Purpose of this Study”).
    This disclosure, in the same reference that discloses
the product having all of the claimed properties, explicitly
or inherently, satisfies the law of anticipation. See In re
Spada, 911 F.2d 705, 708 (Fed. Cir. 1990) (to anticipate,
all of the elements and limitations of the claim must be
found in a single prior art reference). I therefore agree
that the Board’s finding of anticipation is not in error, and
join in affirming that claims 1–6 are invalid on this
ground.
    Claims 7–12: Obviousness
    The Board held that none of the several prior art
combinations showed or suggested the claim limitation
that requires that the product is “annealed at a tempera-
ture greater than 25 ºC and less than the melting point of
the material, approximately 140 ºC.” The Board found
that there was no basis the specification or in the
knowledge of the stilled artisan to expect that an anneal-
ing step should be performed to produce the observed and
effective properties. The Board found that “the Examiner
and Requester have not shown that, more likely than not,
the skilled artisan would have recognized that the desired
beneficial properties would be achieved at temperatures
below 140 ºC by optimizing these parameters.” 2014 WL
1729260 at *15.
   Neither have my colleagues on this panel made such a
showing or identified any source of such a showing. The
4                HOWMEDICA OSTEONICS CORP.    v. ZIMMER, INC.

Arrhenius equation of the relation between chemical
reaction rate and temperature says nothing about genera-
tion or destruction of free radicals or cross-linking or
abrasion resistance or any other characteristic of the
process or the product. Heat-treatment of a polymeric
product may indeed increase cross-linking, and it may
also melt the product, which is inimical to cross-linking,
and may also degrade and destroy the product. The
premises by which the panel majority selects the patent’s
temperature and time and reaction sequence are not
shown or suggested in any reference.
    The Lue reference shows heating the UHMWPE for 1
hour at 150 ºC followed by either slow cooling or shock
cooling. This heat treatment was performed to investi-
gate its effects on both crystallinity and tensile properties
of UHMWPE and allow for additional comparison be-
tween the irradiated UHMWPE and UHMWPE not
subjected to irradiation. Lue performs this step above the
melting point of the UHMWPE, which is inconsistent with
the annealing process that strengthens the prosthetic
product. The Howmedica patent illustrates annealing at
50 ºC for 144 hours, well below he melting point of the
UHMWPE. No application of the Arrhenius equation
suggests that a prior art heating of a molten polymer at
150 ºC for 1 hour renders obvious the annealing of a solid
product for 144 hours at 50 ºC.
    In this crowded field of scientific investigation, anoth-
er scientist, Lawton, uses prolonged heating below the
melting point of the UHMWPE to eliminate crystallinity
and render the product amorphous. However, the Board
correctly found no suggestion in the prior art to modify
the Lue process by heating at the Lawton temperature
range. Only perfect judicial hindsight renders it obvious
to do so—although not even judicial hindsight can find a
teaching or suggestion that these procedures should be
combined to highly beneficial effect.
 HOWMEDICA OSTEONICS CORP.   v. ZIMMER, INC.             5

    The Board correctly reasoned that a skilled artisan
would not have expected or predicted to achieve “the
particular recited properties without hindsight reliance on
the annealing times and temperatures” taught by
Howmedica. Id. The Board’s conclusion, reached on
thorough analysis and sound scientific reasoning, was not
contradicted by any evidence. Indeed, the panel majori-
ty’s holding that “[t]he Board’s finding that a skilled
artisan would not have reasonably expected that modify-
ing Lue according to Lawton would generate UHMWPE
with the recited properties lacks substantial evidence
support” is unjustified. Maj. Op. 21. To the contrary, the
Board in this Reexamination appears to have been ex-
ceedingly through in its treatment of all factual issues
raised before it. I wish every Board decision was as clean
and well-reasoned.
    Substantial evidence “means such relevant evidence
as a reasonable mind might accept as adequate to support
a conclusion.” Consol. Edison Co. v. NLRB, 305 U.S. 197,
229 (1938); see In re Morsa, 713 F.3d 104, 109 (Fed. Cir.
2002).    Such evidence surely exists in the Board’s
thoughtful and considered findings.
    I would affirm the Board’s ruling sustaining the valid-
ity of claims 7–12. I respectfully dissent from my col-
leagues’ reversal of the Board’s decision as to these
claims.