  United States Court of Appeals
      for the Federal Circuit
                ______________________

              SMITH & NEPHEW, INC.,
                    Appellant,

                           v.

  TERESA STANEK REA, Acting Director, United
      States Patent and Trademark Office,
                    Appellee,

                          AND

                  SYNTHES (U.S.A.)
                       Appellee.
                ______________________

                      2012-1343
                ______________________

    Appeal from the United States Patent and Trademark
Office, Board of Patent Appeals and Interferences in
Reexamination Nos. 95/000,465 and 90/009,377.
                 ______________________

                 Decided: July 9, 2013
                ______________________

    JOSEPH R. RE, Knobbe, Martens, Olson, & Bear, LLP,
of Irvine, California, argued for appellant. With him on
the brief was CHRISTY G. LEA. Of counsel on the brief
were ROBERT A. KING and DAVID A. KELLY, Hunton &
Williams, LLP, of Atlanta, Georgia; and BRADLEY T.
2                             SMITH & NEPHEW, INC.   v. REA

LENNIE, RODGER L. TATE, and JEFFREY B. VOCKRODT, of
Washington, DC.

    KRISTI L. R. SAWERT, Associate Solicitor, United
States Patent and Trademark Office, of Alexandria,
Virginia, argued for appellee, United States Patent and
Trademark Office. With her on the brief was BRIAN T.
RACILLA, Associate Solicitor. Of counsel was Nathan K.
Kelley, Deputy Solicitor.

    DAVID R. BAILEY, Woodcock Washburn LLP, of Phila-
delphia, Pennsylvania, argued for appellee, Synthes
(U.S.A.). With him on the brief were WILLIAM F. SMITH
and JOHN F. MURPHY.
                ______________________

    Before DYK, BRYSON, and WALLACH, Circuit Judges.
BRYSON, Circuit Judge.
    Appellant Smith & Nephew, Inc., seeks review of a
decision of the Board of Patent Appeals and Interferences
(now known as the Patent Trial and Appeal Board).
Reversing the decision of a patent examiner, the Board
held that certain claims of a patent owned by appellee
Synthes (U.S.A.) would not have been obvious and there-
fore were not invalid. Both Synthes and the Acting Direc-
tor of the Patent and Trademark Office have filed briefs
supporting the Board’s decision. While the “substantial
evidence” standard of review for the Board’s factual
findings makes Smith & Nephew’s burden on appeal a
heavy one, we are satisfied, after careful review, that
Smith & Nephew has met that burden and has shown
that the claims at issue would have been obvious. We
therefore reverse the decision of the Board.
 SMITH & NEPHEW, INC.   v. REA                           3
                                 I
    Synthes owns U.S. Patent No. 7,128,744 (“the ’744 pa-
tent”). The patent was issued in 2006, and it claims
priority to a provisional application filed on September 13,
1999. The patent is directed to a system for using plates
to repair bone fractures in long bones, such as the femur.
The bone plate that is the subject of the patent runs along
the outside of the fractured bone and is attached by bone
anchors (typically, bone screws) that are inserted through
predrilled holes in the plate and then into the bone. The
dispute in this case focuses on the structure of the holes
in the plate through which the screws are inserted.
    In 2009, Smith & Nephew requested reexamination of
the ’744 patent, and the Patent and Trademark Office
granted the request. After reviewing detailed evidentiary
submissions, the examiner rejected all 55 claims of the
’744 patent as obvious based on a number of prior art
references. Synthes appealed the rejections to the Board
of Patent Appeals and Interferences, which upheld the
rejections of 31 of the claims (claims 24–31 and 33–55),
but reversed the rejections of 24 of the claims (claims 1–
23 and 32). Smith & Nephew appeals from the Board’s
decision with respect to the 24 claims on which the Board
reversed the rejections.
                                 A
    The parties have treated claim 1 as representative of
the 24 claims of the ’744 patent that survived the reexam-
ination, and we do the same. Claim 1 recites a bone
plating system for improving the stability of a bone frac-
ture in a long bone, comprising a bone plate having a
shaft portion that is configured to run along a portion of
the bone and a head portion that flares out from the shaft
portion so as to accommodate the wider portion of the
bone near a joint. The head portion has at least three
bone anchor holes, all of which are conically tapered from
4                               SMITH & NEPHEW, INC.   v. REA
the top surface of the plate to the bottom surface. 1 All of
the holes in the head portion are at least partially thread-
ed to engage the threads on the head of a “locking” bone
anchor (or screw). The shaft portion of the claimed plate
has a plurality of holes in which at least a portion of the
hole is threaded. The central issue in this case is whether
it would have been obvious at the time of the invention to
design a bone plate in which all of the holes in the plate’s
head portion were conically tapered and at least partially
threaded to engage threaded “locking” screws.
    The ’744 patent describes two basic types of screws
that were used in prior art bone plates. First are non-
locking compression screws, which have threaded shafts
but unthreaded heads and which typically pass through
unthreaded holes in the plate. Upon being tightened, the
compression screws draw the bone and plate together.
Second are locking screws, which have threaded heads as
well as threaded shafts. The threads on the heads of the
locking screws engage with corresponding threads on the
interior of the anchor holes in the plate, which results in
fixing the screws to the plate.
    The two types of screws perform different functions:
compression (non-locking) screws draw the bone and the
plate together for fracture reduction and quicker healing,
while locking screws fix the relative position of the plate
and bone so that the plate does not move relative to the
bone. See ’744 patent, col. 1, line 64–col. 2, line 7. The
latter feature is especially important when the bone is a
weight-bearing bone that is subject to pressure that can
loosen the connection between the screws and the plate if


    1  Smith & Nephew argues that the Board erred in
construing the claim to require that all of the holes in the
head be conically tapered. It is unnecessary to decide that
issue to resolve the invalidity contention, so for present
purposes we accept the Board’s construction of the claim.
 SMITH & NEPHEW, INC.   v. REA                          5
only conventional compression screws are used to attach
the plate to the bone.
    Several commercial bone plates, as well as articles
and descriptions of bone plates, are acknowledged to be
prior art to the ’744 patent. First is a condylar buttress
plate that Synthes marketed in the 1990s. Designed for
fractures in the femur near the knee, the Synthes plate
had a shaft and head portion, both of which contained
unthreaded holes designed for compression screws.
    A 1997 article by Kenneth Koval described a modified
version of the Synthes condylar buttress plate. In the
Koval plate, threaded nuts were welded onto the top of
four of the six holes in the head portion of the plate,
enabling the use of locking screws in those holes.
     In a 1998 prior art submission to the Food and Drug
Administration, referred to as the K982222 application,
Synthes sought permission to market a plate having four
threaded holes and two unthreaded holes in the head
portion of the plate. That device, like the Koval plate,
allowed locking screws to be used in the head portion.
The Koval plate and the K982222 application followed the
suggestion in a 1996 article by Brett R. Bolhofner (one of
the inventors of the ’744 patent) and others, which noted
a means of solving the problem that screws “can angulate
. . . and are not fixed in a constant relationship” to the
plate by “selective locking of the screws to the plate.”
    In 1997, N.P. Haas published an article describing a
version of the Synthes plate that used only conically
tapered, threaded holes in the shaft and head portions of
the plate. Unlike other prior art plates, this one merely
stabilized the femur and did not compress or even contact
bone fragments directly.
    The prior art background also included plates for frac-
tures not involving the femur. During the 1990s Synthes
marketed a Distal Radius Plate (“DRP”) for wrist frac-
6                              SMITH & NEPHEW, INC.   v. REA
tures. The anchor holes of the DRP were all partially
threaded and, importantly, were specifically designed for
use with either locking screws or non-locking, compres-
sion screws. In 1997 Synthes marketed another device,
known as the Locking Reconstruction Plate (“LRP”),
which was designed to serve as an internal fixation plate
for a lower jaw fracture. That plate, and a patent applica-
tion for a similar device that ultimately issued as U.S.
Patent No. 5,709,686 (“the ’686 patent”), featured anchor
holes that were all partially threaded and were intended
to accommodate either locking screws or compression
screws. 2 The screw holes in the LRP had a threaded
lower portion and an unthreaded, conically flared upper
portion that enabled the screws to be countersunk so that
the heads of the screws did not extend above the surface
of the plate.
    At the conclusion of the reexamination, the examiner
rejected all of the claims of the ’744 patent. He rejected
the claims at issue in this appeal based on three separate
combinations of prior art references: the K982222 applica-
tion and the Haas article; the Koval and Haas articles;
and the Synthes device and the Haas article. In the
examiner’s view, combining any of the bone plates in the
prior art with the conically tapered, threaded holes used
in the Haas reference taught all the limitations of the
claims in dispute. As for the motivation to combine
features in the prior art, the examiner adopted Smith &
Nephew’s argument that the claimed configuration was
an attractive option because using locking screws would
maximize the stability of the head of the plate, and using
threaded screw holes would give the surgeon the option
during surgery to use either locking screws or compres-
sion screws in the threaded holes, depending on whether


    2 The ’686 patent does not specify what fractures the
invention was intended to mend.
 SMITH & NEPHEW, INC.   v. REA                             7
compression or stabilization was preferred at the particu-
lar position of each of the plate holes.
                                 B
    On appeal, the Board reversed the rejections as to
claims 1–23 and 32. The Board concluded that it would
not have been obvious to modify the condylar buttress
plate in the prior art by having only threaded holes in the
head portions of that plate. The Board acknowledged that
persons of skill in the art would have been motivated to
include threaded holes for locking screws in the head
portion. 3 However, the Board concluded that the prior art
references suggested only that some of the holes in the
head portion should be partially or wholly threaded, not
that all of them should be partially or wholly threaded.
The Board further concluded that the evidence of record
was insufficient to show that inserting conventional
screws in the tapered, threaded holes recited in claim 1
could impart compression between the head portion of the
buttress plates and the bone, and for that reason the
Board held that the examiner’s obviousness analysis was
not “based on adequate rational underpinnings.”
     The Board acknowledged that the specification of the
’744 patent referred to the ’686 patent, which disclosed a
bone plate in which all of the holes were partially thread-
ed, and that the specification stated that the partially
threaded holes of the ’686 patent “allow either non-locking
or locking screws to be used.” ’744 patent, col. 2, ll. 17–18.
However, the Board distinguished the holes described in
claim 1 of the ’744 patent from the holes of the ’686 patent
on the ground that the former were “conically tapered
from the upper surface to the lower surface” of the plate,

    3 Both parties’ experts agreed that a person of skill in
the art would include an orthopedic surgeon with two
years’ experience in the design or implantation of bone
plates or similar orthopedic implants.
8                                 SMITH & NEPHEW, INC.   v. REA
while the holes of the ’686 patent “include an unthreaded
conically flaring area . . . and a separate threaded straight
portion.” A hole that is conically tapered from the upper
surface to the lower surface, the Board stated, is disclosed
in the record only by the threaded holes of the Haas prior
art reference. Because the holes disclosed in Haas were
not shown to accept non-locking screws that would allow
for compression, the Board concluded that the evidence
did not establish that partially threaded plate holes that
are conically tapered from the upper surface to the lower
surface were known to be suitable for use with both
locking and non-locking screws.
    The Board rejected the argument that a person of or-
dinary skill in the art would have used conventional bone
screws in the conical tapered holes of Haas, partly on the
ground that the heads of the screws would “sit[] high atop
the plate,” thereby causing patient discomfort and other
possible complications. The Board relied on the declara-
tion of one of Synthes’s experts, Clifford H. Turen, who
stated that a conventional condylar plate screw had a
“rounded-bottom head” that would stick out from a conical
hole. The Board noted that the Haas plates used cham-
fers to countersink its screws into conical holes, but it
found that the chamfering shown in Haas “is very small
and shallow,” and therefore could not be used to counter-
sink conventional condylar buttress plate screws.
                             II
    The Synthes prior art condylar buttress plate disclos-
es most of the limitations of claim 1 of the ’744 patent. It
consists of a bone plate with a shaft portion having arched
cut-outs on its lower surface. The head portion contains
at least three screw holes. The modifications of that plate
represented by the Koval and K982222 prior art refer-
ences contain four holes in the head portion that are
partially threaded to engage the threads on the head of a
locking screw. The Haas secondary reference includes
 SMITH & NEPHEW, INC.   v. REA                          9
holes in the head portion that are both conically tapered
and partially threaded. The photographs below show the
prior-art Synthes condylar buttress plate and the conical,
partially threaded holes of Haas:




                        Synthes Plate




           Haas’s conical, partially threaded holes

    The essence of the analysis that led the Board to over-
turn the examiner’s decision can be summarized as fol-
lows: The prior art references did not teach or suggest the
exclusive use of conical, partially threaded holes in a
condylar buttress plate because it was not believed that
those holes could be used with non-locking screws to
provide compression. While the ’744 specification stated
that the partially threaded holes of the ’686 patent could
be used with non-locking screws to obtain compression,
the Board did not treat that admission as fatal to Syn-
10                               SMITH & NEPHEW, INC.   v. REA
thes’s case because the holes in the plates of the ’686
patent were not fully conical from the top surface to the
bottom surface of the plate, as required by claim 1. And
although the holes in the Haas plate were both threaded
and fully conical, the Board determined that one of ordi-
nary skill would not have used a standard screw in the
kind of hole disclosed in Haas because there was no
evidence that conical, partially threaded holes were
known to be suitable for use with both non-locking and
locking screws, and because using a conventional bone
screw in a conical tapered hole with a small chamfer, as
in Haas, would result in the screw head sitting unaccept-
ably high above the bone plate.
                             A
     There are several problems with the Board’s analysis.
     First, to the extent that the Board based its ruling on
its conclusion that it would not have been obvious to use a
standard compression screw in a threaded hole to obtain
compression, the Board overlooked the fact that claim 1 of
the ’744 patent did not require that the head screws
provide compression. If a physician regarded it as prefer-
able to have stabilization rather than compression in the
head portion of a bone plate, an obvious solution would
have been to use more threaded holes and locking screws
in that part of the plate. Contrary to Synthes’s suggestion
that compression is invariably needed in the head portion
of condylar buttress plates, the ’744 specification indicates
that locking screws are sometimes used in all of the
threaded holes of the head portion of the bone plate. ’744
patent, col. 6, ll. 47–50 (“generally, threaded holes 56b,
56c [the screw holes in the head portion] are arranged so
that the inserted locking screws converge toward each
other”). As an alternative to using all locking screws in
the head holes, the specification provides that non-locking
screws can be substituted for locking screws in any of
those holes “if a surgeon elects.” Id. Accordingly, the
 SMITH & NEPHEW, INC.   v. REA                           11
embodiment in which locking screws are used in all of the
head screw holes would not provide compression in the
head portion of the plate, but would still be within the
scope of claim 1.
     Second, the Board’s conclusion that using a standard
compression screw in a conical, partially threaded hole
would cause the screw to protrude above the line of the
plate is the result of not reading the prior art for all that
it teaches. The plate hole illustrated in Haas contains a
chamfer, and it is undisputed that a chamfer can be used
to countersink a screw head so that it does not sit above
the top surface of the plate. 4 The Board’s observation
that the chamfer in Haas is narrow ignores the point that
the disclosure of a chamfer is not limited to the precise
size of the chamfer depicted in the illustration of the Haas
device. Chamfers are conventional features in the art and
can be sized to accommodate screw heads of varying
heights. Nothing about the Haas reference limits the size
of the chamfer or in any way suggests that it could not be
made larger than it appears to be in the drawings con-
tained in the Haas reference. In any event, even the
illustrations in the Haas reference make clear that the
chamfer in Haas is large enough to allow the screw to be
countersunk so that it does not protrude above the level of
the plate. That portion of the Board’s analysis therefore
does not provide a basis for disregarding the chamfer
disclosed in Haas. 5


    4  Synthes argues that Smith & Nephew waived this
argument by not presenting it in its appeal briefs to the
Board. However, because the Board considered and
rejected the argument as properly raised, we may review
that determination.
    5  Figures 9 and 22 of the ’744 patent demonstrate
that, even in the claimed invention, the screw may pro-
trude above the surface of the plate. Synthes does not
12                             SMITH & NEPHEW, INC.   v. REA
    Even if countersinking were not an option, a person of
ordinary skill would not have had to use a screw with a
“rounded-bottom head” that would stick out from the
plate. Instead, a conically shaped screw could sit in the
Haas holes without any risk of protrusion. The ’744
specification states, as a general proposition, that “any
surgical screw that has a non-threaded head . . . of an
appropriate size and geometry for select plate holes of the
bone plate can be used” in the claimed bone plate. ’744
patent, col. 4, ll. 20–22. The patent thus suggests the
choice of any appropriate screw design rather than limit-
ing the choice to a screw that would sit too high in a
conical hole.
     Third, the Board’s reliance on the fact that the par-
tially threaded holes in the ’686 patent are only partly
conical (and partly cylindrical) does not undermine the
’744 patent’s admission that partially threaded holes,
regardless of their shape, could provide compression.
Neither the Board nor Synthes has argued that there is
anything about the Haas fully conical shape that would
suggest that a standard, non-locking screw could not have
been used in such a hole to achieve compression. As
already noted, the ’744 specification indicates that “any
surgical screw that has a non-threaded head . . . of an
appropriate size and geometry” can be used to practice the
invention. ’744 patent, col. 4, ll. 20–22. The patent
confirms what common sense suggests: a person of skill
could adjust a plate hole’s geometry—whether conical,
cylindrical, or otherwise—to fit any standard screw with-
out sacrificing compression. In fact, in the portion of its
opinion upholding some of the examiner’s rejections, the
Board specifically found that although the prior art
plates—Synthes, Koval, K982222, and Haas—all used a

indicate what constitutes an “unacceptably high” screw
position, or why countersinking could not have been used
to limit or avoid the protrusion problem.
 SMITH & NEPHEW, INC.   v. REA                           13
“different type of threaded holes for receiving correspond-
ing locking screws, use of any of those threaded holes
[including the fully conical holes of Haas] would have
been obvious to one of ordinary skill.”
     The discussion of the ’686 patent in the ’744 specifica-
tion does not focus on the fact that the holes of the ’686
patent are only partially conical. Instead, the discussion
indicates that because the holes of the ’686 patent are
partially threaded, either locking or non-locking screws
can be used. Curiously, the ’744 specification goes on to
state that “[b]ecause the plate holes are only partially
threaded, the locking screws used may not be able to
maintain the fixed angular relationship between the
screws and plate under physiological loads.” ’744 patent,
col. 2, ll. 18-21. Yet the disputed claims of the ’744 patent
recite that the holes in the head portion of the plate have
“at least a portion that has a thread to engage a thread on
a head of a bone anchor.” Thus, the ’686 patent cannot be
distinguished on the ground that its holes are only par-
tially threaded, since the claims of the ’744 patent them-
selves recite holes that may be only partially threaded.
    To the extent that the ’744 specification distinguished
the ’686 patent on the ground that the threads in the
holes of the ’686 patent do not entirely surround the
locking screw (a point made by one of Synthes’s experts),
the difference between a thread that surrounds the screw
and one that only partially surrounds the screw is one of
degree only and is not a distinction on which validity
turns. Not surprisingly, the Board did not rely on that
distinction in its decision.
    The ’744 specification’s description of the ’686 patent
therefore discloses that the prior art used non-locking
screws in threaded holes. Because that prior art refer-
ence demonstrated that non-locking screws could achieve
compression in either type of hole, the motivation to
combine the Haas holes with the condylar plates was
14                             SMITH & NEPHEW, INC.   v. REA
clear: The use of threads in all of the holes would offer
the advantage of added flexibility for the surgeon, who
could choose to use locking or non-locking screws in any of
the holes in the head portion of the plate.
    Fourth, the Board refused to consider two prior art
references, the DRP and the LRP, which, like the ’686
patent, disclosed the use of non-locking screws in thread-
ed holes. The Board discounted those references on the
ground that the examiner had not relied on them as a
basis for his rejections. The examiner, however, incorpo-
rated Smith & Nephew’s arguments by reference, includ-
ing its discussion of those two references. The references
were clearly probative as to whether it was known at the
time of the invention that non-locking screws could be
used in threaded holes. As such, they supported Smith &
Nephew’s rebuttal of Synthes’s argument that the combi-
nation of the prior art condylar buttress plates with Haas
would have rendered the prior art plates inoperable, on
the theory that compression could not be obtained without
at least some unthreaded holes in the head portion of the
plate.
    Synthes marketed the LRP and the DRP in the 1990s.
The LRP was intended to deal with mandible fractures.
In its brief to the Board, Synthes admitted that the plate
holes in the LRP were designed so that the holes could
“either be used to form a locking construct or a non-
locking construct.” That was because the holes had a
lower threaded portion for providing a locking function
with locking screws and an unthreaded upper portion “for
providing a seating surface for use with the unthreaded
head of a standard [compression] screw.”
     The DRP was intended to deal with wrist fractures.
That plate featured holes in the “distal arm” portion of
the plate that were all partially threaded and were specif-
ically designed for use with either locking screws or non-
locking, compression screws. Although Synthes notes
 SMITH & NEPHEW, INC.   v. REA                          15
that neither the LRP nor the DRP are used with weight-
bearing bones and therefore use holes with only “minimal
threading,” that does not meaningfully distinguish them
from the claimed invention, which also requires only
partially threaded holes.
    Finally, as already noted, the ’686 patent disclosed
the use of partially threaded holes to accommodate either
locking or non-locking screws. Synthes acknowledged as
much in the specification of the ’744 patent. That intrin-
sic evidence from the ’744 specification was plainly rele-
vant and admissible to rebut Synthes’s argument that
such a structure would not have been obvious because it
would not have worked.
    We recognize, of course, that the “substantial evi-
dence” standard of review requires a deferential approach
to the Board’s findings. In re Gartside, 203 F.3d 1305,
1316 (Fed. Cir. 2000). In this case, however, the facts are
largely undisputed, and the Board’s decision regarding
the obviousness of including only threaded holes in the
head portion of the condylar plate was mainly the result
of the analytical errors discussed above, not the Board’s
resolution of factual questions. 6 Accordingly, we conclude


   6  To the extent that Synthes sought to create a factu-
al dispute through the declaration of Dr. Turen that “one
of ordinary skill in the art would not have thought it to
have been obvious to replace all of the unthreaded holes
in the head portion of the plates disclosed in the primary
references,” that statement is contrary to the statement in
the patent that the prior art taught partially threaded
holes that “allow either non-locking or locking screws to
be used,” ’744 patent, col. 3, ll. 17–18, as well as the LRP
and DRP references. Expert opinions that are contrary to
admissions in the specification do not create a factual
issue. See Pharmastem Therapeutics, Inc. v. Viacell, Inc.,
491 F.3d 1342, 1361–62 (Fed. Cir. 2007).
16                               SMITH & NEPHEW, INC.   v. REA
that the Board erred in ruling that removing the non-
threaded holes from the head portion of the prior art
plates would not have been expected to allow the plates to
impart compression between the head portion and the
bone.
                             B
    Given the compelling evidence that it would have
been obvious to modify any one of the three primary
references to have only threaded holes in the head por-
tion, the sole remaining feature that distinguishes the
plate system of claim 1 from the prior art condylar plate
systems using partially threaded holes is the fully conical
shape of the holes in the plate recited in claim 1. And
that feature is found in the secondary reference, Haas.
Accordingly, the critical remaining question is: Would it
have been obvious to a person of ordinary skill in the art
to combine the partially threaded holes of the Synthes
device, the Koval article, or the K982222 submission with
the partially threaded, conical holes of Haas?
    The evidence before the Board does not indicate that
the choice of a fully conical hole, as opposed to a partially
conical hole, would produce a surprising result or involve
anything more than a choice among designs already found
in the prior art. Synthes has not suggested that using a
fully conical hole, as opposed to a hole that is partially
conical and partially cylindrical, confers some significant
advantage, nor is there anything in the ’744 specification
to suggest any such advantage. 7 Moreover, the prior art
made clear that after substituting conical, partially
threaded holes for the unthreaded holes in the head
portion, the device still “would have worked for its intend-
ed purpose,” even assuming Synthes’s contention that

     7 Synthes has not relied on any objective indicia of
non-obviousness, such as commercial success, to buttress
its case.
 SMITH & NEPHEW, INC.   v. REA                          17
achieving compression was the primary intended function
of the claimed plate. DePuy Spine, Inc. v. Medtronic
Sofamor Danek, Inc., 567 F.3d 1314, 1326 (Fed. Cir.
2009). This case is therefore one that falls within the
Supreme Court’s characterization of obviousness as
entailing an improvement that is no “more than the
predictable use of prior art elements according to their
established functions.” KSR Int’l Co. v. Teleflex Inc., 550
U.S. 398, 417 (2007).
     Both in its brief and at oral argument, Synthes ar-
gued that achieving compression with non-locking screws
in conically tapered, partially threaded holes was un-
known in the prior art and, in fact, would have been
inoperable. This naturally raises the question of how
Synthes managed to make such a combination work.
Obtaining compression in threaded holes, according to
Synthes, became possible only through the use of a “spe-
cialized” or “specially-designed” screw devised for that
purpose. But the patent does not claim or otherwise
disclose any such “specially designed” screw. Upon being
pressed at oral argument to identify the “specially de-
signed screw” to which Synthes alluded in its brief, coun-
sel for Synthes pointed to Figure 1 of the patent. That
figure, however, is not identified in the patent as a “spe-
cialized” or “specially designed” screw. To the contrary,
the specification refers to Figure 1 as merely “an example
of a non-locking screw” and states that “any surgical
screw that has a non-threaded head . . . of an appropriate
size and geometry for select plate holes of the bone plate
can be used.” ’744 patent, col. 4, ll. 18–22.
    The problem with Synthes’s argument is that it is
contending that a standard non-locking screw would be
inoperative to obtain compression in a threaded hole,
while at the same time claiming that it managed to
achieve exactly that objective, all through the deus ex
machina of a “specialized screw.” But an unclaimed and
undisclosed feature such as the “specialized screw” cannot
18                               SMITH & NEPHEW, INC.   v. REA
be the basis for finding Synthes’s patent to be non-obvious
over the prior art. See E.I. Du Pont de Nemours & Co. v.
Phillips Petroleum Co., 849 F.2d 1430, 1433 (Fed. Cir.
1988), quoting McCarty v. Lehigh Valley R. Co., 160 U.S.
110, 116 (1895) (“[N]o principle of law . . . would authorize
us to read into a claim an element which is not present,
for the purpose of making out a case of novelty . . . .”). 8
    The patentability of the invention at issue in this case
turns on the structure of the holes, not the special nature
of the non-locking screw that is to be used with those
holes. The conical, partially threaded holes themselves
were well known in the art, as was the advantage of
adding more of them to the head of a condylar bone plate
in place of unthreaded holes. Both the screws and the
holes perform their conventional, expected function in
securing the plate. Because we hold that the examiner
correctly ruled that disputed claims would have been
obvious, we reverse the decision of the Board.
                       REVERSED




     8  Counsel for the Acting Director specifically dis-
claimed reliance on any “specialized screw” supposedly
disclosed in the patent.
