Federal Circuit disposition — 2011-1239

United States Court of Appeals
for the Federal Circuit
__________________________
(Serial No. 10/643,674)
IN RE SUONG-HYU HYON AND MASANORI OKA
__________________________
2011-1239
__________________________
Appeal from the United States Patent and Trademark
Office, Board of Patent Appeals and Interferences.
___________________________
Decided: May 24, 2012
___________________________
G EORGE D. M OUSTAKAS , Harness, Dickey & Pierce,
PLC., of Troy, Michigan, argued for appellant. With him
on the brief was DAVID L. SUTER.
AMY J. NELSON , Associate Solicitor, United States
Patent and Trademark Office, of Alexandria, Virginia,
argued for appellee. With her on the brief were RAYMOND
T. CHEN , Solicitor, and JANET A. G ONGOLA, Associate
Solicitor. Of counsel was SCOTT C. WEIDENFELLER , Asso-
ciate Solicitor.
__________________________

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IN RE HYON 2
Before NEWMAN and BRYSON , Circuit Judges, and FOGEL,
District Judge.1
Opinion for the court filed by Circuit Judge BRYSON .
Dissenting opinion filed by Circuit Judge NEWMAN .
BRYSON , Circuit Judge.
This appeal arises from the examination of Reissue
Application No. 10/643,674 (“the reissue application”),
which stemmed from U.S. Patent No. 6,168,626 (“the ’626
patent”). During prosecution, the examiner rejected all
claims of the reissue application on two independent
grounds: (1) obviousness over U.S. Patent No. 5,030,402
(“Zachariades”) in view of U.S. Patent No. 3,886,056
(“Kitamaru”), and (2) impermissible recapture of subject
matter surrendered during the original prosecution under
35 U.S.C. § 251. The Board affirmed the examiner’s
rejection on both grounds. We agree with the Board that
the claims of the reissue application would have been
obvious in light of the prior art. We therefore affirm on
that basis, and we do not address the portion of the
Board’s decision regarding the recapture issue.
I
The ’626 patent is entitled “Ultra High Molecular
Weight Polyethylene [“UHMWPE”] Molded Article for
Artificial Joints and Method of Preparing the Same.” As
the title suggests, the claims of the ’626 patent and the
reissue application are directed toward UHMWPE and,
more specifically, UHMWPE for use in artificial joints.
1 Honorable Jeremy Fogel, District Judge, United
States District Court for the Northern District of Califor-
nia, sitting by designation.

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IN RE HYON 3
Reissue claim 40, which is generally representative of the
reissue claims on appeal, recites:
40. A method for producing an ultra high mo-
lecular weight polyethylene block, com-
prising:
(a) crosslinking an ultra high molecular
weight polyethylene block having a mo-
lecular weight not less than 5 million by
irradiating the block with a high energy
radiation at a level of at least 1 MR;
(b) heating said crosslinked block up to a
compression deformable temperature be-
low the melting point of the UHMWPE;
(c) subjecting said heated block to pres-
sure; and then
(d) cooling said block.
Reissue claim 84 is substantially the same as claim 40,
except that the preamble recites “[a] method for producing
an ultra high molecular weight polyethylene artificial
joint component for implantation in a human or other
animal,” and it adds an additional step (e), which recites
“processing said cooled block to form said component.”
In rejecting the claims of the reissue application as
obvious, the Board relied on the same two references
invoked by the examiner: Zachariades and Kitamaru.
Zachariades discloses a method for producing UHMWPE
having a molecular weight of three million to six million.
In particular, Zachariades teaches compression deforma-
tion of UHMWPE at a temperature between 80º C and the
melting point of the polymer, applying pressure during

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IN RE HYON 4
and after cooling to retain chain orientation, subjecting
the final product to radiation crosslinking after unmold-
ing, and then shaping the deformed UHMWPE into a
final product. Kitamaru discloses a method for preparing
UHMWPE by first crosslinking the UHMWPE by irradi-
ating it with ionizing radiation, then heating the
crosslinked UHMWPE to a molten state at a temperature
of at least the melting point of the polyethylene while it is
extended or compressed under pressure (i.e., compression
deformed), and then cooling the polyethylene while main-
taining it in an extended or compressed state. Kitamaru
teaches that its method of crosslinking before compression
results in a product that has a higher melting or softening
point, improved transparency, and excellent dimensional
stability.
During prosecution, the examiner found that Zacha-
riades meets each limitation of the reissue claims except
for the step of crosslinking the UHMWPE prior to com-
pression. The examiner, however, found that Kitamaru
discloses crosslinking the UHMWPE prior to compression.
The examiner then found that it would have been obvious
to a person of ordinary skill in the art to use crosslinked
UHMWPE in the method of making the UHMWPE prod-
ucts disclosed by Zachariades given Kitamaru’s teaching
that crosslinking prior to compression deformation results
in improved transparency, an increased melting point,
and excellent dimensional stability. The examiner fur-
ther found that one of ordinary skill in the art would have
had a reasonable expectation of success in obtaining those
enhanced properties by combining the techniques taught
by the two references.

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IN RE HYON 5
On appeal to the Board, Hyon2 did not challenge the
examiner’s findings as to what the references teach, and
the Board expressly adopted the examiner’s findings in
that respect. Instead, Hyon argued only that there would
have been no motivation to combine the teachings of
Zachariades and Kitamaru. The Board rejected that
argument, agreeing with the examiner that a person of
ordinary skill in the art would have been motivated to
combine the references. Specifically, the Board found
that Zachariades and Kitamaru “teach the same material
(UHMWPE) and Kitamaru teaches benefits of . . . cross-
linking before deformation of the UHMWPE.” It also
found that “Kitamaru focuses on cross-linking prior to
extending as the reason for providing the improved prop-
erties,” and that “the art provides the focus on using the
cross-linking step prior to molding.” The Board concluded
that using the technique disclosed by the claims of the
reissue application “appears to be nothing more than the
predictable use of a prior art element (i.e., cross-linking
prior to molding) according to its established function
(i.e., to improve material properties such as [by increas-
ing] the melting point).”
The Board considered and expressly rejected Hyon’s
arguments that a motivation to combine was lacking
because the references are directed to different products
(Zachariades to artificial joints; Kitamaru to films or
sheets). The Board noted that both references are di-
rected to UHMWPE, and that Zachariades teaches struc-
tures with “reduced thickness” or a “thinner load” having
enhanced mechanical properties. The Board also ex-
pressly rejected Hyon’s argument that one of ordinary
skill in the art would not have been motivated to combine
the pre-compression crosslinking step of Kitamaru with
2 We refer to the applicants collectively as “Hyon.”

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IN RE HYON 6
Zachariades. Instead, it found that “Kitamaru provides
the reason for modifying Zachariades to cross-link before
extending: to provide UHMWPE articles with improved
dimensional stability and transparency at high tempera-
tures.” In addition, the Board rejected Hyon’s claim that
the references fail to teach further processing to make a
final product after deforming and cooling the UHMWPE.
On that issue, the Board found that Zachariades teaches
“machining into a final product.” Accordingly, the Board
affirmed the examiner’s rejection of all the claims of the
reissue application.
II
As he did before the Board, Hyon challenges only the
Board’s determination that there was a motivation to
combine the references; he does not challenge the Board’s
determination as to what the references teach.3 The
“existence of a reason for a person of ordinary skill to
combine references” is a question of fact that we review
for substantial evidence. In re Constr. Equip. Co., 665
F.3d 1254, 1255 (Fed. Cir. 2011). Because the Board’s
findings concerning motivation to combine are supported
by substantial evidence, we affirm.
Hyon argues that one of ordinary skill in the art
would not be motivated to combine the references because
Zachariades is directed to artificial joints whereas Ki-
tamaru is directed to films or sheets, which Hyon con-
3 The dissent suggests that Hyon’s method requires
only a “slight amount” of crosslinking, whereas Kitamaru
teaches a “high dose.” However, Hyon has not raised that
distinction either before the Board or on appeal to this
court. In fact, Hyon explicitly noted during prosecution
that the amount of crosslinking radiation “is [not] limited
to any particular numerical dosage range.”

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IN RE HYON 7
tends represent “fundamentally different material tech-
nologies.” As noted above, however, both Zachariades and
Kitamaru pertain to UHMWPE. Although Zachariades
primarily contemplates the use of the polyethylene for
artificial joints, it generically discloses “a method for
producing an UHMWPE product with enhanced planar
mechanical properties.” Similarly, although Kitamaru
primarily contemplates the use of the polyethylene to
generate films and sheets, it generically discloses a “proc-
ess for producing a high melting temperature polyethyl-
ene.” Neither reference limits the structure of the
UHMWPE product that can be made; artificial joints
(Zachariades) and sheets (Kitamaru) are simply embodi-
ments of the polyethylene made by each process. More-
over, the distinction between the final products described
in the two references is not as great as Hyon suggests. As
the Board noted, Zachariades states that its recited
method can be used to create thin products, Zachariades,
col. 2, ll. 44, 66-67; col. 3, ll. 46-47, and discusses products
that are “transparent,” id., col. 9, ll. 29-30, 48. Accord-
ingly, the Board’s conclusion that the references both
teach processes directed to making the same class of
products is supported by substantial evidence, as is its
determination that differences in the UHMWPE products
described by the embodiments do not negate the motiva-
tion to combine the references.
Substantial evidence also supports the Board’s deter-
mination that the fact that Zachariades teaches crosslink-
ing after molding does not affect the motivation to
combine. Zachariades does not state that UHMWPE
products can be made only by crosslinking after compres-
sion deformation, nor does it state or suggest that faulty
or inferior products will result from crosslinking prior to
compression. The Board found that “Kitamaru teaches
benefits of . . . cross-linking before deformation of the

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IN RE HYON 8
UHMWPE.” It also found that “Kitamaru focuses on
cross-linking prior to extending as the reason for provid-
ing the improved properties,” and that “the art provides
the focus on using the cross-linking step prior to molding.”
As noted above, Kitamaru teaches that its method results
in a product that has a higher melting or softening point,
improved transparency, and excellent dimensional stabil-
ity.4
For similar reasons, Hyon’s argument that the Board
improperly relied on the arbitrary selection of a single
feature from Kitamaru (pre-compression crosslinking)
while ignoring the other features is not persuasive. In
support of his position, Hyon relies on In re Wesslau, 353
F.2d 238 (CCPA 1965), which states:
It is impermissible within the framework of sec-
tion 103 to pick and choose from any one reference
only as much of it as will support a given position,
to the exclusion of other parts necessary to the full
appreciation of what such reference fairly sug-
gests to one of ordinary skill in the art.
353 F.2d at 241. In this case, however, the Board did not
take the teachings of Kitamaru in isolation or out of
context. As noted above, the Board found that one of skill
in the art would appreciate that the pre-compression
4 At oral argument, Hyon contended that Zacha-
riades could not be combined with Kitamaru because the
molding step of Zachariades would not work if the
UHMWPE were crosslinked first, as the crosslinking
would inhibit molding. Because that argument was not
presented to the Board or in Hyon’s briefs to this court,
we decline to address it. See Sage Prods., Inc. v. Devon
Indus., Inc., 126 F.3d 1420, 1426 (Fed. Cir. 1997). In any
event, Hyon failed to adduce any evidence that crosslink-
ing prior to molding would inhibit molding.

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IN RE HYON 9
crosslinking step could be combined with Zachariades to
obtain beneficial results. Both references involve simi-
larly structured UHMWPE, and Zachariades does not
disparage pre-compression crosslinking. Kitamaru ex-
pressly notes that crosslinking to improve the properties
of UHMWPE was known in the art, but that the prior art
methods did not result in increased melting point or
improved transparency. Kitamaru teaches that its
method results in a product with those improved proper-
ties. In addition, as found by the Board, Kitamaru “fo-
cuses on cross-linking prior to extending as the reason for
providing the improved properties.” Accordingly, it is
clear that the examiner and the Board selected the pre-
compression crosslinking step because Kitamaru indi-
cated that pre-compression crosslinking was responsible
for the improved properties. Given Kitamaru’s discussion
of crosslinking in the prior art and its focus on pre-
compression crosslinking as a reason for the improved
properties of polyethylene produced using its method, we
cannot say that the Board “exclud[ed] . . . other parts [of
the reference] necessary to the full appreciation of what
such reference fairly suggests to one of ordinary skill in
the art.” Wesslau, 353 F.2d at 241. The Board merely
selected an element emphasized by the reference, relying
on the reference’s suggestion that the selected element
was responsible for the improved properties. Considering
the references as a whole, as required by Wesslau, we
conclude that the Board’s determination regarding moti-
vation to combine is supported by substantial evidence.
Finally, substantial evidence supports the Board’s de-
termination that Zachariades teaches post-processing to
form a final component, as required by claim 84 of the
reissue application. For example, Zachariades states that
“[t]he product is simultaneously shaped into the final
product”; that the compression-deformed product “can be

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IN RE HYON 10
cut off by stamping or other process”; and that “the so-
produced solid-state deformed UHMWPE can be used as a
precursor for its machining into a final product.” Those
statements are sufficient to support the Board’s finding
that Zachariades teaches post-processing to form a final
component.
III
In sum, substantial evidence supports the Board’s
finding that a person of ordinary skill in the art would
have been motivated to combine the early crosslinking
step of Kitamaru with the process of Zachariades to
obtain the enhanced properties disclosed by Kitamaru
that result from crosslinking prior to deformation. We
therefore affirm the Board’s determination that the
reissue claims would have been obvious in light of the
prior art. Accordingly, we need not address whether the
reissue claims impermissibly sought to recapture subject
matter surrendered during the original prosecution in
violation of 35 U.S.C. § 251.
AFFIRMED

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United States Court of Appeals
for the Federal Circuit
__________________________
(Serial No. 10/643,674)
IN RE SUONG-HYU HYON AND MASANORI OKA
__________________________
2011-1239
__________________________
Appeal from the United States Patent and Trademark
Office, Board of Patent Appeals and Interferences.
__________________________
NEWMAN , Circuit Judge, dissenting.
This case reaches us on appeal from the PTO’s rejection,
on the ground of obviousness, of all of the claims presented
in this reissue divisional application of U.S. Patent No.
6,168,626 (the ’626 patent). The patent, entitled “Ultra
High Molecular Weight Polyethylene Molded Article for
Artificial Joints and Method of Preparing the Same,” is
directed to artificial joints having low friction and improved
abrasion resistance due to the molecular and crystal orien-
tation of this ultra high molecular weight polyethylene
(UHMWPE).
The Hyon procedure and its effects are not shown or
suggested in any reference, despite the long history and
extensive scientific studies of all forms of polyethylene.
From the court’s endorsement of the Board’s flawed analy-
sis, I must, respectfully, dissent.

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IN RE HYON 2
D ISCUSSION
The ’626 patent was issued on January 2, 2001 with
eleven claims. On May 8, 2002, Hyon requested that the
patent be reissued with 262 additional claims, stating, as
the reissue statute requires, that he had, through error and
without deceptive intent, claimed less than he was entitled
to claim. This assertion entitled Hyon to a full examination
of all of the proffered claims. See 37 C.F.R. §1.176(a) (“A
reissue application will be examined in the same manner as
a non-reissue, non-provisional application, and will be
subject to all the requirements of the rules related to non-
reissue applications.”); see also Manual of Patent Examina-
tion Procedure (MPEP) §1440 (“[A]n original claim, if repre-
sented in a reissue application, will be fully examined in the
same manner, and subject to the same rules as if being
presented for the first time in an original non-reissue,
nonprovisional application . . . .”).
The reissue claims on this appeal are directed to a
method of producing a UHMWPE block or artificial joint
component, whereby a controlled amount of irradiation is
applied to the article to introduce a “very small amount” of
cross-linking, followed by heating and compression–
deformation of the molded article. The ’626 patent summa-
rizes the method as follows:
This UHMWPE molded article having molecular
orientation or crystal orientation can be obtained by
irradiating a low dose of a high energy ray to a raw
UHMWPE molded article to introduce a very small
amount of crosslinking points in polymer chains so
as to be crosslinked slightly, then by compression-
deforming the crosslinked UHMWPE molded article
after heating up to its compression-deformable tem-

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IN RE HYON 3
perature, and by cooling the molded article while
keeping the deformed state.
’626 patent, col.2 ll.46-55. This appeal concerns twenty-
seven claims of the reissue divisional application, of which
claims 40, 41, and 84 can be viewed as representative:
40. A method for producing an ultra high molecular
weight polyethylene block, comprising:
(a) crosslinking an ultra high molecular weight
polyethylene block having a molecular weight not
less than 5 million by irradiating the block with a
high energy radiation at a level of at least 1 MR;
(b) heating said crosslinked block up to a com-
pression deformable temperature below the melting
point of the UHMWPE;
(c) subjecting said heated block to pressure; and
then
(d) cooling said block.
41. A method for producing an ultra high molecular
weight polyethylene block according to Claim 40,
wherein said irradiation is gamma irradiation at a
level of from 1 MR to 5 MR.
84. A method for producing an ultra high molecular
weight polyethylene artificial joint component for
implantation in a human or other animal, compris-
ing:
(a) crosslinking an ultra high molecular weight
polyethylene block having a molecular weight not
less than 5 million by irradiating the block with a
high energy radiation at a level of at least 1 MR;
(b) heating said crosslinked block up to a com-
pression deformable temperature below the melting
point of the UHMWPE;

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IN RE HYON 4
(c) subjecting said heated block to pressure;
then
(d) cooling said block; and
(e) processing said cooled block to form said
component.
The reissue examiner, affirmed by the Board, held all of the
claims unpatentable on the ground of obviousness over U.S.
Patent No. 5,030,402 to Zachariades (July 9, 1991) in view
of U.S. Patent No. 3,886,056 to Kitamaru et al. (May 27,
1975). The Zachariades patent, entitled “Process for Pro-
ducing a New Class of Ultra-High-Molecular-Weight Poly-
ethylene Orthopaedic Prostheses with Enhanced
Mechanical Properities,” describes a process that starts with
heating the polyethylene, deforming it by compression, and
cooling the deformed polyethylene. Zachariades mentions
the optional post-processing condition of radiation cross-
linking, as follows:
The final product 19 in FIG. 2D can be separated
from the perimeter mass 18 by stamping or other
process after its removal from the mold 10, or after
thermal (annealing) or post-processing conditions,
e.g., radiation cross-linking.
’402 patent, col.6 ll.50-54. The reissue examiner acknowl-
edged that there is a difference between Zachariades and
Hyon, stating that for Zachariades cross-linking may be
performed after deformation of the polymer, whereas Hyon
requires a “slight amount” of cross-linking before deforma-
tion. Examiner’s Answer at 6 (Dec. 29, 2009) (“The differ-
ence from the instantly claimed method is that Zachariades
does not mention crosslinking UHMWPE by irradiation
before compression deformation.”). The examiner held that
the Kitamaru reference filled this gap.

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IN RE HYON 5
The Kitamaru patent, entitled “Process for Producing a
High Melting Temperature Polyethylene Employing Irradia-
tion and Orienting,” describes a process for treating poly-
ethylene fibers and films in which radiation cross-linking is
the first step, followed by melting, stretching while molten
(optionally under pressure), and cooling. Kitamaru de-
scribes the process as follows:
In accordance with the present invention, the
starting polyethylene is first crosslinked by irradia-
tion with an ionizing radiation so as to produce
crosslinked polyethylene having a gel content of at
least one weight percent.
… [T]he crosslinked polyethylene is then ex-
tended or stretched in the molten state at a tem-
perature of at least anisotropic melting point of the
polymer. . . . Conventional extending means are ap-
plicable to the invention. For example, a conven-
tional continuous drawing equipment may be used
for stretching polyethylene fibers and films. Fur-
ther, rolling and inflation apparatuses known in the
art can be used for polyethylene films. If transpar-
ent polyethylene film or sheet is to be obtained, it is
preferable to conduct the extending under an in-
creased pressure. . . .
The crystallization subsequent to the extending
in the molten state can be conducted at any tem-
perature, because the rate of crystallization under
the extended state is extremely rapid. Actually, af-
ter extending of crosslinked sample in the molten
state, products having many advantageous proper-
ties such as very high melting temperature, excel-
lent mechanical properties, excellent transparency
and etc. are obtained independent of the condition
for the crystallization.

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IN RE HYON 6
’056 patent, col.2 ll.45-49, col.3 ll.11-43.
Kitamaru is directed to cross-linking and extending
polyethylene fibers and films, and does not relate to produc-
ing a polyethylene mass suitable as an artificial joint having
advantageous mechanical properties and dimensional
stability. It is noteworthy that Zachariades, seeking me-
chanical strength and dimensional stability, did not follow
the known Kitamaru processing sequence, but instead cross-
linked the polyethylene after deformation, not before.
Nonetheless, the examiner held that a person of ordinary
skill in the field of the invention would have known to do
what neither Kitamaru nor Zachariades did, and would
have known or expected that this departure would produce
“low friction and remarkably improved abrasion resistance,”
in the words of Hyon’s ’626 patent, col.2 ll.59-60. The exam-
iner concluded:
It would have been obvious to one skilled in the
art at the time of the invention to irradiate
UHMWPE, as taught by Kitamaru et al in an
analogous method, to provide a slightly crosslinked
irradiated UHMWPE perform [sic: preform] as the
starting UHMWPE to be used in the compression
molding method steps for orienting and extending
UHMWPE taught by Zachariades.
Examiner’s Answer, at 6.
It is not disputed that neither Kitamaru nor Zacha-
riades shows or suggests starting with slight cross-linking of
the UHMWPE, followed by heating and compression defor-
mation. Nonetheless, the Board found that the Hyon
method “appears to be nothing more than the predictable
use of a prior art element . . . according to its established

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IN RE HYON 7
function.” Board op. at 10. The Board does not explain the
source of its prediction, other than the Hyon method itself.
The Board held that a person of ordinary skill would
have expected to combine aspects selected from the Zacha-
riades and Kitamaru processes. As to which aspects to
select and combine, the only guidance comes from Hyon, for
the prior art contains no “apparent reason to combine the
known elements in the fashion claimed by the patent at
issue.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418
(2007). The Board reasoned backward from the Hyon
method, to hold that since Kitamaru cross-linked prior to
extending fibers and films, it was obvious to modify Zacha-
riades by slightly cross-linking the bulk polymer prior to
molding. The Board stated:
Kitamaru focuses on cross-linking prior to extend-
ing as the reason for providing the improved proper-
ties. Accordingly, the art provides the focus on
using the cross-linking step prior to molding.
Based on the art’s focus on cross-linking prior to
molding to improve the properties of the material,
using such a technique appears to be nothing more
than the predictable use of a prior art element (i.e.,
cross-linking prior to molding) according to its es-
tablished function (i.e., to improve material proprie-
ties such as increase the melting point).
Board op. at 10. However, Hyon stated in the ’626 patent
that a high dose of radiation (as in Kitamaru) did not im-
prove abrasion resistance: “[T]hough the irradiation of an
ultra high dose of γ-ray was tried for improving the
UHMWPE, it was made clear that coefficient of abrasion
increases and abrasion loss does not decrease.” ’626 patent,
col.1 ll.61-64.

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IN RE HYON 8
The Board’s suggestion that it was obvious to perform
the method that neither Zachariades nor Kitamaru per-
formed nor suggested, is supported solely by the teaching in
Hyon’s patent. See In re Fritch, 972 F.2d 1260, 1266 (Fed.
Cir. 1992) (“It is impermissible to use the claimed invention
as an instruction manual or ‘template’ to piece together the
teachings of the prior art so that the claimed invention is
obvious.” (quoting In re Gorman, 933 F.2d 982, 987 (Fed.
Cir. 1991)); see also Interconnect Planning Corp. v. Feil, 774
F.2d 1132, 1138 (Fed. Cir. 1985) (“The invention must be
viewed not with the blueprint drawn by the inventor, but in
the state of the art that existed at the time.”).
When the technologic field is mature, apparently small
changes that produce unexpected results or improved prop-
erties are of heightened significance. Nothing in the record
suggests that a person of ordinary skill would have foreseen
that Hyon’s method of slight radiation cross-linking followed
by heating and compression deformation would produce the
described benefits. See In re Gartside, 203 F.3d 1305, 1314
(Fed. Cir. 2000) (“the Board’s decision must be justified
within the four corners of th[e] record”).
The Board cited no reason to expect that the Hyon
method would produce a superior polyethylene artificial
joint. Zachariades, like Hyon, recognized the problem, and
stated that “the fabrication of ultra-high-molecular-weight
polyethylene products to achieve enhanced mechanical
properties and good dimensional stability is a challenging
task.” ’402 patent, col.2 ll.39-42. Zachariades commented
that “it is very difficult to control this important parameter
[good dimensional stability].” Id. at col.2 ll.28-29. Hyon in
the ’626 patent also pointed to the difficulty of improving
UHMWPE properties, stating that “it is regarded that any
improvement in dynamic properties of the UHMWPE by
chemical modification reached its limitation, and it is re-

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IN RE HYON 9
garded to be difficult to obtain a UHMWPE molded article
having a more excellent abrasion resistance and lower
friction.” ’626 patent, col.2 ll.5-9. The ’626 patent explains
the Hyon improvement:
[T]he present inventors tried to obtain a molded ar-
ticle of a low friction and to improve an abrasion re-
sistance by introducing molecular orientation or
crystal orientation into a finished product by means
of, not a chemical modification method, but a physi-
cal modification method.
This approach has never been attempted, not
only in Japan, but also in other countries. The idea
to endow the polyethylene molded article for artifi-
cial joints with molecular orientation or crystal ori-
entation is the very creative, and it is sure that this
invention, if actually carried out, will be applied to
artificial joints all over the world.
Id. at col.2 ll.26-37. It is only after Hyon demonstrated how
to achieve this improved result that the Board was able to
plug the prior art steps into the template of the Hyon
method. However, as explained in Interconnect, 774 F.2d at
1143, “[w]hen prior art references require selective combina-
tion by the court to render obvious a subsequent invention,
there must be some reason for the combination other than
the hindsight gleaned from the invention itself.”
The Kitamaru and Zachariades references describe dif-
ferent sequences and degrees of cross-linking, heating and
cooling, and stretching and deformation. Zachariades
compresses solid polyethylene below its melting tempera-
ture and then cross-links it, and Kitamaru cross-links fiber
or film and then melts and stretches it. Neither of these
references, nor any other authority, suggests that the Hyon
steps would achieve the Hyon improvement. As stated in

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IN RE HYON 10
Life Technologies, Inc v. Clontech Laboratories, Inc., 224
F.3d 1320, 1326 (Fed. Cir. 2000), “[r]easonable expectation
of success is assessed from the perspective of the person of
ordinary skill in the art. That the inventors were ultimately
successful is irrelevant to whether one of ordinary skill in
the art, at the time the invention was made, would have
reasonably expected success.” See also In re Vaeck, 947 F.2d
488, 493 (Fed. Cir. 1991) (“[T]he reasonable expectation of
success must be founded in the prior art, not in the appli-
cant’s disclosure.”).
The selective combination of aspects of Kitamaru and
Zachariades is achieved only with hindsight knowledge of
Hyon’s achievement, for nothing in either reference or
elsewhere in the prior art suggests this modification. The
Court in KSR cautioned that “[a] factfinder should be
aware, of course, of the distortion caused by hindsight bias
and must be cautious of arguments reliant upon ex post
reasoning.” 550 U.S. at 421. The Board’s analysis is con-
trary to the Court’s guidance. In In re Lee, 277 F.3d 1338,
1344 (Fed. Cir. 2002) this court stated that “[i]t is improper,
in determining whether a person of ordinary skill would
have been led to this combination of references, simply to
‘[use] that which the inventor taught against its teacher.’”
(quoting W.L. Gore v. Garlock, Inc., 721 F.2d 1540, 1552
(Fed. Cir. 1983) (alteration in original)). See also In re Dow
Chem. Co., 837 F.2d 469, 472-73 (Fed. Cir. 1988).
The Board erred in its analysis, for “the factual inquiry
whether to combine references must be thorough and
searching.” McGinley v. Franklin Sports, Inc., 262 F.3d
1339, 1351-52 (Fed. Cir. 2001). I respectfully dissent from
the court's endorsement of the Board’s flawed analysis.

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