Baxter Healthcare Corp.v.Millenium Biologix, LLC

Patent Trial and Appeal Board

Mar 18, 2015

12022946 (P.T.A.B. Mar. 18, 2015)

Trials@uspto.gov Paper 48
Tel: 571-272-7822 Entered: March 18, 2015

UNITED STATES PATENT AND TRADEMARK OFFICE
_______________
BEFORE THE PATENT TRIAL AND APPEAL BOARD
_______________
BAXTER HEALTHCARE CORP.,
APATECH, INC., and APATECH LIMITED,
Petitioner,

v.

MILLENIUM BIOLOGIX, LLC,
Patent Owner.

Case IPR2013-00582
Patent RE41,251 E
_______________

Before MICHELLE R. OSINSKI, SCOTT E. KAMHOLZ, and
BRIAN P. MURPHY, Administrative Patent Judges.

MURPHY, Administrative Patent Judge.

FINAL WRITTEN DECISION
35 U.S.C. § 318(a) and 37 C.F.R. § 42.73

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I. INTRODUCTION

Baxter Healthcare Corp., ApaTech, Inc., and ApaTech Limited
(“Petitioner”) filed a Petition (Paper 1, “Pet.”) requesting inter partes review
of claims 1, 6, and 8–13 of U.S. Patent No. RE41,251 E (Ex. 1001, “the ’251
patent”). On March 21, 2014, we instituted an inter partes review of the
challenged claims on the following grounds of unpatentability asserted by
Petitioner:
Reference[s] Basis Claims challenged
Davies
1
§ 102(b) 1 and 8–13
Davies and Ichitsuka
2
§ 103(a) 8
Ruys ’93a
3
§ 102(b) 1 and 8–13
Ruys ’93a and
Bioceramics
4

§ 103(a) 6
Decision to Institute (Paper 8, “Dec.”) 30.
Patent Owner Millenium Biologix, LLC (“Patent Owner”) filed a
Patent Owner Response (Paper 20, “PO Resp.”), and Petitioner filed a Reply
(Paper 23, “Pet. Reply”).
Patent Owner did not file a motion to amend claims, but Patent Owner
did file a motion to exclude certain of Petitioner’s evidence (Paper 28, “PO
Mot. Excl.”). Petitioner filed an Opposition (Paper 37) and Patent Owner
filed a Reply (Paper 41). Petitioner filed a motion to exclude certain of
Patent Owner’s evidence (Paper 30, “Pet. Mot. Excl.”). Patent Owner filed

1
WO94/26872 to Davies, published November 24, 1994 (Ex. 1015).
2
EP267624 to Ichitsuka et al., published May 18, 1988 (Ex. 1024).
3
Ruys, A Feasibility Study of Silicon Doping of Hydroxyapatite, 42 INT’L
CERAM. REV. 6 (1993) (Ex. 1011).
4
AN INTRODUCTION TO BIOCERAMICS (Larry L. Hench & June Wilson eds,
1993) (Ex. 1021).
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an Opposition (Paper 36) and Petitioner filed a Reply (Paper 42).
Petitioner relies on declarations of Dr. Antonios G. Mikos in support
of its Petition (Ex. 1003) and Reply (Ex. 1134). Petitioner further relies on
the declaration of Dr. Karin Hing (Ex. 1136) in support of its Reply. Patent
Owner relies on the declaration of Dr. Joo L. (Anson) Ong in support of its
Response (Ex. 2026). Petitioner relies on deposition testimony of Dr. Ong
(Ex. 1133) in support of its Reply. Patent Owner relies on deposition
testimony of Dr. Mikos (Ex. 2028; Ex. 2055), including its Motion for
Observations on Cross-Examination of Dr. Mikos (Paper 33, “PO Obs.”), to
which Petitioner filed a Response (Paper 38).
We heard oral argument on November 14, 2014. A transcript is
entered as Paper 47 (“Tr.”).
We have jurisdiction under 35 U.S.C. § 6(c). This final written
decision is entered pursuant to 35 U.S.C. § 318(a) and 37 C.F.R. § 42.73.
We determine Petitioner has shown by a preponderance of the
evidence that claims 1 and 8–13 are unpatentable under 35 U.S.C. § 102(b)
and claim 6 is unpatentable under 35 U.S.C. § 103(a).
Petitioner’s Motion to Exclude Evidence is dismissed as moot.
Sections I–III of Patent Owner’s Motion to Exclude Evidence are
dismissed as moot. Section IV is denied.
A. Related Proceedings
The ’251 patent is the subject of litigation in the Northern District of
Illinois, Millenium Biologix, LLC v. Baxter Healthcare Corp., Civil Action
No. 1:13-cv-03084 (N.D. Ill.). Pet. 2; Ex. 1123. The ’251 patent is related
to U.S. Patent No. 6,585,992, certain claims of which are the subject of the
petition in IPR2013-00590 on which we instituted trial. Id. Our Final
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Written Decision in IPR2013-00590 is being entered concurrently with this
Decision.
B. The ’251 Patent
The ’251 patent is directed to a synthetic biomaterial compound based
on stabilized calcium phosphates and adapted for supporting bone cell
activity. Ex. 1001, Title, Abstract. The compound, an embodiment of
which is referred to in the patent as “Skelite,” has treatment applications for
the repair and restoration of natural bone compromised by disease, trauma,
or genetic influences. Id. at 1:25–33. The compound can be made in
different forms, one of which is a macroporous structure of interconnected
voids having a pore size of approximately 50 to 1000 microns that can serve
as a scaffold for the integration of new bone tissue. Id. at 21:56–62, 27:1–
13. The compound is made by sintering a fine precipitate of a calcium
phosphate material at high temperature (in the range from 800º C to 1100º C.
(id. at 28:55–60)) in the presence of a stabilizing additive having an ionic
radius of a size that enables substitution into the Ca—P lattice. Id. at 5:31–
35. The ’251 patent discloses that silicon, having an ionic radius of 0.40Å,
is a preferred additive used to stabilize the claimed compound such that it “is
essentially insoluble in biological media but is resorbable when acted upon
by osteoclasts.” Id. at 5:39–41.
The ’251 patent describes a process for preparing the claimed calcium
phosphate biomaterial compound by “processing . . . a fine precipitate,
formed from a colloidal suspension and stabilized using an additive . . . that
enables substitution into the Ca—P lattice.” Ex. 1001, 5:31–35. The
characteristic features of the claimed compound “arise during sintering,”
which provides the conditions necessary to enable silicon substitution into
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the Ca—P lattice and interconnection of particles to form a microporous
structure. Id. at 5:49–54. Formation of a microporous structure is at the
heart of the dispute between the parties.
A graphic example of sintering, which causes hydroxyapatite (“HA”)
particles to fuse together, is shown below in Figure 1, chapter 11 of
Bioceramics.
5

Figure 1, chapter 11 of Bioceramics is a schematic of the sintering
process.
Ex. 1021, 129. In the example above, a pore is formed by the fusion of four
hydroxyapatite particles during sintering. Id. at 128–29. Bioceramics states
that the “porosities are usually classified as comprising either micropores
(having a diameter of several microns due to the incomplete sintering of the
particles) or macropores (having a diameter of several hundred microns
allowing bone ingrowth.).” Id. at 129. Bioceramics also teaches that
“microporous” hydroxyapatite can have pore sizes smaller than one micron,

5
Hydroxyapatite, Ca5(OH)(PO4)3, is a calcium phosphate biomaterial
compound that is the primary inorganic component of natural bone. Ex.
1001, 2:66–3:6.
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even as small as 2 to 5 nanometers (0.002 to 0.005 microns) in diameter. Id.
at 119; Ex. 1133, 157:5–13, 158:1–13; Ex. 1134 ¶ 148. Bioceramics,
therefore, is instructive for its teaching of how one of ordinary skill in the art
would understand the term “microporous.”
The ’251 patent is a reissue of U.S. Patent No. 6,323,146. Claims 1,
6, and 8 are illustrative and reproduced below. Italicized text indicates
language that was added to the claims upon reissuance of the patent.
Bracketed text indicates language that was removed.
1. An isolated bioresorbable biomaterial compound comprising
calcium, oxygen and phosphorous, wherein a portion of at least
one of said elements is substituted with an element [having an
ionic radius of approximately 0.1 to 0.6 Å] Si
4+
, wherein said
compound has a microporous structure.

6. The biomaterial compound as claimed in claim [5] 1 wherein
said compound is formed as a macroporous structure
comprising an open cell construction with interconnected voids
having a pore size of approximately 50 to 1000 microns.

8. The biomaterial compound as claimed in claim 5, wherein
said compound has a nanoporous structure.
6

6
Claim 8 depends from a claim canceled in reissue. For purposes of this
decision, we interpret claim 8 as depending from claim 1.

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II. DISCUSSION

A. Claim Construction
In an inter partes review, claim terms in an unexpired patent are given
their broadest reasonable interpretation in light of the patent specification.
37 C.F.R. § 42.100(b); In re Cuozzo Speed Tech., LLC, No. 2014–1301,
2015 WL 448667, *7–*8 (Fed. Cir. Feb. 4, 2015). Claim terms are given
their ordinary and customary meaning, as would be understood by one of
ordinary skill in the art in the context of the entire disclosure. In re
Translogic Tech., Inc., 504 F.3d 1249, 1257 (Fed. Cir. 2007). “The
specification ‘is the single best guide to the meaning of a disputed term.’”
Id. (quoting Phillips v. AWH Corp., 415 F.3d 1303, 1315 (Fed. Cir. 2005).
Any special definition for a claim term must be set forth in the specification
with reasonable clarity, deliberateness, and precision. In re Paulsen, 30 F.3d
1475, 1480 (Fed. Cir. 1994).
1. “isolated . . . compound”
Petitioner argues the broadest reasonable interpretation of “isolated
. . . compound” consistent with the specification is “a multi-phasic mixture
containing a substituted-TCP
[7]
phase, which has been separated from other
starting materials used to synthetically or otherwise prepare that multi-phase
compound.” Pet. 15 (citation omitted). Petitioner points out that the ’251
patent specification does not use the word “isolated” to describe any calcium

7
TCP stands for tricalcium phosphate, one of several calcium phosphate
species. Ex. 1001, 3:4–15.
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phosphate compound.
8
Pet. 14. Petitioner emphasizes that the word
“isolated” was added to the claim by amendment during prosecution of the
original patent prior to reissue. Id. (citing Ex. 1009, 269–274).
Claim 1 recites a silicon-substituted bioresorbable biomaterial
compound “comprising calcium, oxygen and phosphorous.” The silicon-
substituted calcium, oxygen, and phosphorous compounds disclosed in the
’251 patent are stabilized calcium phosphates synthesized and isolated as
calcium phosphate “phases” or as a calcium phosphate “phase.” Ex. 1001,
Title,
9
4:24–28, 5:4–5, 11:14–23, 13:40–61, and Figs. 9, 10, and 16. The
’251 patent summary of invention states that a silicon-substituted calcium
phosphate (silicon “substituted into the Ca—P lattice”) “typically coexists
with hydroxyapatite, and is itself a novel stabilized calcium phosphate
compound having a microporous morphology . . . .” Id. at 5:31–39.
Although silicon-substituted TCP is identified and claimed as a preferred
compound (Id. at 6:5–7 and 34:22–27), the ’251 patent states that “[s]pecific
compounds of the present invention include but are not limited to” silicon-
substituted TCP. Id. at 6:5–7. The ’251 patent priority application
10

repeatedly and consistently refers to stabilized calcium phosphate phases “to
include the various calcium phosphate species in the sintered product such
as hydroxyapatite, α-TCP, β-TCP, calcium octophosphate, tetracalcium

8
The ’251 patent uses the term “isolated” only in reference to an unrelated
description of osteoclast cells isolated from bone marrow to permit in vitro
observation of osteoclast activity. Ex. 1001, 3:41–4:8.
9
“Synthetic Biomaterial Compound of Calcium Phosphate Phases
Particularly Adapted for Supporting Bone Cell Activity.”
10
The ’251 patent claims priority to WO 97/09286 through a chain of
continuation-in-part applications.
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phosphate and dicalcium phosphate.” Ex. 1017, 12:17–20 (emphasis
added); see also Ex. 1001, 20:62–21:10. Silicon substitution stabilizes a
calcium phosphate phase or phases such that they “maintain a consistent
crystallographic and chemical structure when placed in ambient conditions
or in a physiological environment in vivo or in vitro” (Ex. 1017, 12:6–9) and
are “essentially insoluble in biological media” (Ex. 1001, 5:39–41).
In light of the above and contrary to Petitioner’s argument, the
claimed “isolated . . . compound” is not limited to compounds including a
silicon-substituted TCP phase. Claim 1 uses the open-ended phrase
“comprising calcium, oxygen and phosphorous,” which includes several
different calcium phosphate species in addition to TCP, as indicated in the
’251 patent specification and priority application discussed above. The
open-ended language of claim 1 also contrasts with the narrower Markush
group language contained in independent claims 15 (Si-substituted TCP) and
22 (several Si-substituted calcium phosphate species). See, e.g., Abbott
Labs. v. Andrx Pharm., Inc., 473 F.3d 1196, 1210 (Fed. Cir. 2007) (“A
Markush group is a form of drafting a claim term that is approved by the
PTO to serve a particular purpose when used in a claim—to limit the claim
to a list of specified alternatives.”) (citation omitted). The’251 patent
consistently refers to stabilized “calcium phosphate phases,” without any
indication of intending to limit the claimed compound solely to compounds
including a silicon-substituted TCP phase.
We recognize that Patent Owner added the word “isolated” to
distinguish claim 1 (among others) from Davies during prosecution and
argued that applicants had developed “a stabilized calcium phosphate phase
(claimed in WO 97/09286) from which the presently claimed biomaterial
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compound was then further isolated therefrom.” Ex. 1009, 304. We do not
read this as an intention to limit the claims to a silicon-substituted TCP
phase or as providing a special definition for the claimed “isolated
compound.” See In re Paulsen, 30 F.3d at 1480. An interpretation limiting
the claim only to compounds including a silicon-substituted TCP phase
would contradict Patent Owner’s repeated references to stabilized calcium
phosphate phases, which may be isolated by the processes disclosed in the
’251 patent. Ex. 1001, Title, 4:24–28, 5:4–5 and 31–39, 11:14–23, 13:40–
61, 20:62–21:10, Figs. 9, 10, 16; Ex. 1017, 12:17–20. The open-ended
claim language, the deliberate use of more limiting language in other claims,
the disclosures of the ’251 patent and priority application, and the
prosecution history all counsel against limiting claim 1 to compounds
including a silicon-substituted TCP phase.
11

The word “isolated” in claim 1 is used in accordance with its plain
and ordinary meaning to those skilled in the art—separated from all other
substances. See Ex. 1005, 4 (right-hand column, “
1
isolate,” definition “2”).
12

The isolated compounds disclosed in the ’251 patent are stabilized calcium
phosphates synthesized and isolated as calcium phosphate “phases” or as a
calcium phosphate “phase.” Therefore, we determine that the broadest
reasonable interpretation of “isolated . . . compound” in the context of the
claimed invention, consistent with the ’251 Specification, is “a stabilized

11
Patent Owner does not contest our construction of “isolated . . .
compound” in its Response to the Petition. PO Resp. 22–23.
12
“to separate (as a chemical compound) from all other substances: obtain
pure or in a free state”
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single phase or multi-phase calcium phosphate compound separated from all
other substances.”
2. “microporous structure”
The ’251 patent does not define “microporous structure” as recited in
claim 1. The parties dispute the meaning of “microporous structure.” We
address the parties’ claim construction dispute below.
a. Decision to Institute
Petitioner argues the claimed “microporous structure” means a
structure having pore sizes of about a micron or less. Pet. 19–20. In its
Preliminary Response Patent Owner agreed with Petitioner, subject to the
qualification “so long as the material is indeed porous to the flow of fluids,
i.e. ‘or less’ does not equate to not porous at all.” Prelim. Resp. 27. Patent
Owner’s qualification must be read in light of the ’251 patent’s description
that, at sintering temperatures of 1250º C and above, the silicon-substituted
calcium phosphate particles “show an increasing tendency to form a melt
thus eliminating the microporous structure.” Ex. 1001, 15:39–42. The
implication is that the porosity of the material must not be eliminated by
complete sintering (fusion) of the particles. In our Decision to Institute, we
construed “microporous structure” to mean “a porous structure of
interconnected particles having pore sizes of about 2 microns or less in
diameter.” Dec. 12 (citing Ex. 1001, 5:31–39 (“a microporous morphology
based on inter-connected particles of about 0.2–1.0 µm in diameter”),
13:61–66 (“a range of microporous structures comprised of particles of size
range 0.1 to 2.0 µm”); Ex. 1017, 13:26–29, 17:12–20)).
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b. Patent Owner’s Response and Petitioner’s Reply
Patent Owner argues in its Response that the Board’s construction
requires clarification to limit the claimed “microporous structure” further to
a structure having (i) “interconnected microporosity,” and (ii) pore sizes
greater than 0.1 micron in diameter so as to exclude a “nanoporous
structure.”
13
PO Resp. 55–57. Patent Owner, relying on the Declaration
testimony of Dr. Ong, argues that interconnected microporosity is required
to permit “sufficient percolation of physiological fluids” for cellular
osteoclast and osteoblast activity to carry out bone resorption and bone
growth functions in vivo. Id. at 56–57 (citing Ex. 2026 ¶¶ 91–93). Patent
Owner argues that the ’251 patent defines a microporous structure as
“interconnected round particles with an interconnected microporosity in said
structure.” Id. at 56 (citing Ex. 1001, 8:10–11). Patent Owner further
argues that “no person of skill in the art would understand the claimed
microporous structure to cover the nanoporous structure of claim 8.” Id. at
57 (citing Ex. 2026 ¶ 93).
Petitioner replies that the Board’s construction is correct and
emphasizes Dr. Ong’s agreement that references from the mid-1990s
referred to nanometer-sized pores (e.g., 2–5 nanometers in diameter) as
“microporous.” Pet. Reply 6 (citing Ex. 1133, 157:5–13, 158:1–13; Ex.
1021, 119; Ex. 1134 ¶¶ 143–149). Dr. Mikos adds that not only does the

13
The parties agree that a person of ordinary skill in the art would
understand “nanoporous” to mean a pore size of less than about 0.1 micron
(100 nanometers) in diameter (Pet. 20; Prelim. Resp. 27), an interpretation
supported by the Declarations of Dr. Mikos (Ex. 1003 ¶ 334) and Dr. Ong
(Ex. 2026 ¶ 93).
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’251 patent not require a lower limit on the size of the micropores (Ex. 1134
¶ 146), but many references “clearly show that persons skilled in the art in
fact did use the term ‘micropore’ without a bottom limit, which would
necessarily encompass nanopores.” Ex. 1134 ¶¶ 147, 148 (citing, e.g., Ex.
1047, 5 (“In ceramic structures, micropores (usually less than 5 µm in size)
. . . .”); Ex. 1049, 2 (“Micropores (< 5 µm) . . . .”). Dr. Mikos further opines
that although interconnected pores “facilitate” bioactivity and
bioresorbability of calcium phosphate materials, interconnected pores “are
not required” to attain these properties. Ex. 1134 ¶ 149 (citing Dr. Ong’s
deposition testimony, Ex. 1133, 150:18–151:1 (“Q. So my point is, is that
you don’t necessarily need interconnected pores to have a useful calcium
phosphate material. . . . A. That is correct.”)). Dr. Mikos opines that even a
dense form of HA with little or no porosity is still a useful biomaterial
compound. Ex. 1003 ¶¶ 68, 69 (“dense HA [generally lacking a porous
structure] was considered by some to be more suitable for implantation in
load bearing sites.”) (citation omitted); Ex. 1021, 128–129.
c. Analysis
Claim 1 of the ’251 patent recites “wherein said compound has a
microporous structure.” Claim 1 does not recite a structure having
“interconnected microporosity” or a lower limit on pore size. A comparison
with the language of claim 6 is instructive. Claim 6 depends from claim 1
and recites a “macroporous structure . . . with interconnected voids having a
pore size of approximately 50 to 1000 microns.” Ex. 1001, 33:59–63
(emphasis added). Claim 6, unlike claim 1, expressly limits the porous
structure to one of “interconnected voids” having a pore size within a range
of specific numeric values. Because claim 1 lacks a comparable recitation of
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“interconnected voids” or “interconnected micropores” and a lower limit on
pore size, the claim language itself does not provide a reason to limit the
claim as urged by Patent Owner. See Enzo Biochem, Inc. v. Applera Corp.,
599 F.3d 1325, 1333 (Fed. Cir. 2010) (modifying district court’s claim
construction by removing hybridization requirement because “[Appellants]
knew how to claim [the hybridization requirement], as they did in the
[related] patents.”).
With regard to the issue of “interconnected microporosity,” the ’251
patent consistently describes the microporous structure or morphology of the
claimed compound in terms of interconnected particles exhibiting porosity,
not in terms of interconnected micropores. Figure 5, below, most clearly
shows the microporous structure.

Fig. 5 shows interconnected particles exhibiting porosity.
Ex. 1001, Fig. 5 (“[T]he surface morphology is that of an interconnected set
of rounded particles with a high degree of porosity as seen in FIG. 5.” (id. at
11:50–52)). The patent’s repeated descriptions of interconnected particles,
fused during sintering to form a microporous structure exhibiting porosity,
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do not describe interconnected microporosity as critical or necessary to the
microporous structure of the claimed compound. Id. at 5:37–38 (“compound
having a microporous morphology based on inter-connected particles”);
11:50–52 (“the surface morphology is that of an interconnected set of
rounded particles with a high degree of porosity”); 13:61–64 (“The ceramic
comprises rounded, inter-connected particles . . . with a large degree of
localized porosity.”); 22:3–6 (“A characteristic microporous morphology
that arises from the agglomeration of particles . . . and the sintering of the
material to produce a network of interconnected particles.”); Ex. 1134 ¶ 146.
Patent Owner does not explain how interconnected microporosity results
necessarily from interconnected particles. Interconnected microporosity
may be preferred for supporting percolation of physiological fluids and bone
cell activity,
14
but interconnected microporosity is neither recited in claim 1
nor required for a functional biomaterial. As established by Dr. Mikos’s
testimony and Dr. Ong’s testimony, dense HA (without interconnected
microporosity) is suitable for implantation at load bearing sites in patients.
Ex. 1003 ¶¶ 68, 69; Ex. 1134 ¶ 149 (citing Dr. Ong’s deposition testimony,
Ex. 1133, 150:18–151:1). Therefore, we decline to read “interconnected
microporosity” into the construction of “microporous structure.”
With regard to Patent Owner’s proposed definition of “microporous
structure” as including a lower limit of 0.1 micron pore size, the ’251 patent

14
“According to yet a further aspect of the present invention is a synthetic
sintered microporous polycrystalline structure for supporting bone cell
activity, the structure comprising . . . a globular morphology of
interconnected rounded particles with an interconnected microporosity in
said structure.” (Ex. 1001, 8:10–11; Ex. 2026 ¶¶ 91–92).
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does not claim or describe such a lower limit. Tr. 40:19–25 (“JUDGE
KAMHOLZ: The ’251 patent does not provide definitions of those terms
microporosity and nanoporosity. MR. RUTHERFORD: That is correct . . . .
it doesn’t . . . say, oh yes, nano will be .1 to 1 and micro will be 1 to 3. It
does not set it out in that way.”); see Pet. Reply 6–7 (citing Ex. 1134 ¶ 146
(“[T]he specification does not place a lower limit on the size of the
micropores.”). Although Patent Owner argues that the “microporous
structure” recited in claim 1 cannot include the “nanoporous structure”
recited in claim 8 (PO Resp. 57; Tr. 41:1–11), the language of claims 1 and
8 does not require mutually exclusive pore size ranges. The ’251 patent,
moreover, describes a microporous structure that will vary as a function of
particle size and sintering conditions, which can include pore sizes less than
100 nanometers in diameter. Ex. 1001, 11:52–58, 13:59–66, and Figs. 5,
6(a), 6(b). For example, in describing the microporous morphology of the
preferred Skelite compound, the ’251 patent states that “the underlying
structure of the particles is the agglomeration of granules of size range of
approximately 1 to 20 nm [nanometers],” thereby invoking the prospect of
sintering particles smaller than 0.1 micron (100 nanometers) and forming
concomitantly smaller pores. Ex. 1001, 17:43–45, and Figs. 6(a) (showing
nanoporosity within the body of the sintered particle), 6(b) (showing
underlying unsintered particle size of 5 to 10 nanometers). The only lower
limit on pore size of the microporous structure, which we infer from the
written description of the patent, is that porosity not be eliminated by
complete sintering of the particles. Id. at 15:39–42.
Patent Owner argued during the oral hearing that the ’251 patent
distinguishes the pore sizes of a nanoporous structure from those of a
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microporous structure (Tr. 39:6–18 (citing Ex. 1001, 7:41–42)).
15
Patent
Owner acknowledged, however, that the ’251 patent does not provide
definitions of “microporosity” and “nanoporosity,” and counsel could not
cite evidence in the record to support the assertion that “microporosity” and
“nanoporosity” must have non-overlapping pore size ranges. Tr. 40:19–
41:11. The cited passage from the patent, moreover, does not impose a
lower limit on pore size of a microporous structure or mandate non-
overlapping pore size ranges. Therefore, we are not persuaded by Patent
Owner’s argument. See Aventis Pharma S.A. v. Hospira, Inc., 675 F.3d
1324, 1330 (Fed. Cir. 2012) (proper not to limit plain and ordinary meaning
of claim term “perfusion,” where specification did not express language of
manifest exclusion or clear disavowal of claim scope.).
Our construction also is consistent with the weight of extrinsic
evidence that persons skilled in the art used the terms “microporous” or
“microporosity” to refer to nanometer-sized pores. Ex. 1021, 119
(“microporous HA cement” with “interconnected microporosity averaging
2–5 nm in diameter”); Ex. 1133, 157:5–13, 158:1–13 (confirms use of
“microporous” in Exhibit 1021 page 119 to include pore sizes in the range of
2 to 5 nanometers); Ex. 1134 ¶¶ 143–149 (“microporous structure” includes
nanometer-sized pores without a bottom limit); Ex. 1047, 5 (“In ceramic
structures, micropores (usually less than 5 µm in size) . . . .”); Ex. 1049, 2

15
“The biomaterial compound has a distinguishable microporous and
nanoporous structure along with a crystallography that is similar yet
different from that of α-TCP.” The quoted passage from the ’251 patent was
not cited in Patent Owner’s Response regarding claim construction or in the
cited passages from paragraphs 91–93 of Dr. Ong’s Declaration. PO Resp.
55–57 (citing Ex. 2026 ¶¶ 91–93).
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(“Micropores (< 5 µm) . . . .”). The extrinsic evidence persuades us that one
of ordinary skill in the art of bone implant materials would understand
“microporous” and “microporosity” to refer to a range of pore sizes several
microns or less in diameter without a finite lower limit.
In sum, although a range of particle sizes and sintering conditions
(time and temperature) are described in the ’251 patent for forming a
microporous structure, the ’251 patent does not place a finite lower limit on
pore size so as to exclude nanometer-sized pores from the definition of
“microporous structure,” nor does the extrinsic evidence indicate that such a
limitation was implied in use of that term.
For the reasons given above, we decline to alter our claim
construction as urged by Patent Owner. Therefore, we maintain our
construction of the broadest reasonable interpretation of “microporous
structure” to mean “a porous structure of interconnected particles having
pore sizes of about 2 microns or less in diameter.” Dec. 12.
3. “bioresorbable biomaterial” and “compound comprising
calcium, oxygen and phosphorous, wherein a portion of at
least one of said elements is substituted with an element
Si
4+
”
In our Decision to Institute, we determined that no express
interpretation of the quoted phrases recited in claim 1 is required. Dec. 11–
12. The parties do not contest this determination. We maintain that no
express interpretation of the phrases “bioresorbable biomaterial” and
“compound comprising calcium, oxygen and phosphorous, wherein a
portion of at least one of said elements is substituted with an element Si
4+
” is
required for this Final Written Decision.
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4. “macroporous structure”
In our Decision to Institute, we determined that Claim 6 defines
“macroporous structure” with clarity and precision: “comprising an open
cell construction with interconnected voids having a pore size of
approximately 50 to 1000 microns.” Dec. 13. The parties do not contest this
determination. We maintain our construction of “macroporous structure.”
5. “nanoporous structure”
In our Decision to Institute, we determined the broadest reasonable
interpretation of “nanoporous structure,” recited in claim 8, is “a porous
structure of interconnected particles having pore sizes of less than about 0.1
micron (100 nanometers) in diameter.” Dec. 13. The parties agree and do
not contest this determination. Pet. 20; PO Prelim. Resp. 27. We maintain
our construction of “nanoporous structure.”
B. Anticipation of Claims 1 and 8–13 by Davies
Petitioner argues that Davies (Ex. 1015) discloses the same process
described in the ’251 patent for applying a colloidal calcium phosphate
(CaP) thin film to a quartz substrate, followed by sintering at high
temperatures, which necessarily will result in the claimed isolated
compound. Pet. 32–33 (citing Ex. 1003 ¶¶ 429–438, 608–09, App. B).
Petitioner argues that Davies inherently anticipates claims 1 and 8–13 under
35 U.S.C. § 102(b). Id.; see Schering Corp. v. Geneva Pharmaceuticals,
Inc., 339 F.3d 1373, 1377 (Fed. Cir. 2003) (“[A] prior art reference may
anticipate without disclosing a feature of the claimed invention if that
missing characteristic is necessarily present, or inherent, in the single
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anticipating reference.”) (citation omitted); SmithKlineBeecham Corp. v.
Apotex Corp., 403 F.3d 1331, 1343–44 (Fed. Cir. 2005). Patent Owner
opposes, arguing that the thin-film-on-quartz embodiment is a non-elected,
unclaimed embodiment that is not an “isolated” compound, as recited in
claim 1. PO Resp. 21–25 (citing Ex. 2026 ¶¶ 57–59; Ex. 2028 (Mikos
Depo.)).
1. Overview of Davies
Davies discloses synthetic CaP-based thin films, applied to a quartz
substrate, on which bone cells may be cultured to permit evaluation of bone
cell functional properties such as osteoclast activity. Ex. 1015, Abstract,
6:30–35. Procedure 1 of Davies describes the preparation of HA using a
two-solution sol-gel process, where Solution A (pH 12) is made with 4.722
grams of calcium nitrate and Solution B (pH 12) is made with 1.382 grams
of ammonium dihydrogen phosphate. Ex. 1015, 25:8–26:29; Ex. 1003
¶¶ 432–437. After mixing Solutions A and B followed by centrifugation, a
colloidal CaP sol-gel suspension of HA is formed. Id. Procedure 3
describes cleaning a quartz substrate, which contains silicon, and Procedure
4 describes dip coating the cleaned quartz substrate with the colloidal CaP
sol-gel prepared in Procedure 1. Ex. 1015, 28:17–29:9; Ex. 1003 ¶¶ 434–35.
Procedure 5 describes sintering the CaP-coated quartz substrate at 1000ºC
for one hour. Ex. 1015, 29:11–19; Ex. 1003 ¶ 436. X-ray diffraction
analysis reveals that, when sintered at 1000ºC, “the film has a majority of
tricalcium phosphate and a ratio of approximately 10:90 of calcium
hydroxyapatite [HA] to tricalcium phosphate.” Ex. 1015, 29:20–35. With
regard to claim 1 of the ’251 patent, Davies does not disclose expressly the
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substitution of silicon in at least one of the calcium, oxygen, or phosphorous
elements.
2. Analysis of asserted anticipation of claim 1 by Davies
Petitioner cites the testimony of Dr. Mikos, who testifies that the
“‘isolated compound’ of claim 1 is no different than the multi-phasic
mixtures [of HA and TCP] disclosed in [Davies]” as a CaP thin film
provided on a quartz substrate. Pet.34 (citing Ex. 1003 ¶ 617). Dr. Mikos
further testifies that “[a]s the result of the sintering, the multi-phasic calcium
phosphate-based material has been separated from the environment, that is
the reagents and the unwanted starting materials . . . .” Ex. 2028, 78:5–
79:21. Petitioner argues that the sintering step used in Davies, also used in
the ’251 patent, would have resulted in removal of residual reactants,
thereby yielding the claimed “isolated compound.” Pet. 34–35.
Patent Owner argues that non-election of a claimed method for
culturing functional bone cells on a CaP thin film, in response to a restriction
requirement during prosecution, is evidence that Davies does not disclose
the claimed “isolated compound.” PO Resp. 22. Patent Owner argues that
the “isolated compound” language covers the silicon-substituted powder and
macroporous structure embodiments described in Examples 5 and 8 of the
’251 patent, but not the thin-film-on-quartz embodiment of Example 3. Id.
at 22; see Tr. 82:11–14 (“If you are going to use it [CaP thin film] for
treatment, you would remove it from the quartz . . . . It is not part of the
resulting biomaterial that is being created.”). Patent Owner concludes that
Davies does not disclose a silicon-substituted CaP compound “separated
from all other substances” in accordance with our claim construction. PO
Resp. 22–23 (citing Ex. 2026 ¶¶ 57–59).
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We agree with Patent Owner. The ’251 patent and Davies repeatedly
and consistently describe the compound as a thin film “formed on,”
“provided on,” or “applied to” a quartz substrate. Ex. 1001, 4:11–13 (“a
calcium phosphate-based thin film formed . . . on quartz substrates”), 8:33–
34 (“a synthetic sintered film . . . on a substrate”), 16:54–56 (“As provided
as a film on a substrate . . . .”), 26:25–26 (“Once the colloidal suspension
(sol-gel) is prepared, it may be applied as a thin film to the desired substrate
. . . .”); Ex. 1015, Abstract (“Such film, as applied to a support . . . .”), 10:7–
8 (“providing the film on a transparent supporting substrate, such as quartz
or glass”), 10:24–27 (“Preferably the substrate is of quartz . . . because of the
required sintering of the film once applied to the substrate.”). The thin film
is applied by dipping the quartz substrate into a separately prepared CaP
sol-gel suspension, extracting the substrate from the sol-gel suspension at a
constant speed (“dip coating”), followed by drying and sintering for one
hour at 1000º C. Ex. 1001, 29:27–34; Ex. 1015, 21:35–22:5, 28:34–29:17.
Thus, the thin film is created from the CaP sol-gel suspension and applied to
or coated on the quartz substrate, such that the CaP thin film compound is
bound to, not separated from, another substance.
16

We are persuaded by Dr. Ong’s testimony that Davies does not
disclose that “the sintered CaP thin film could be separated and thus
‘isolated’ from the reagent/substance/substrate on which it was formed.”
Ex. 2026 ¶ 58. The failure of Davies to disclose an “isolated” CaP

16
Quartz is “a mineral consisting of silicon dioxide occurring in colorless
and transparent or colored hexagonal crystals or in crystalline masses.”
Quartz Definition, MERRIAM-WEBSTER, available at http://www.merriam-
webster.com/dictionary/quartz (last visited February 20, 2015). Ex. 3001.

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compound is further supported by the prosecution history of the ’251 patent.
Ex. 1009, 295. The Examiner withdrew a Section 102(b) rejection over
Davies (and WO 97/09286), advising patent applicant to “point out [Davies
and WO 97/09286] do not teach isolated compounds and have different
formulas.” Id. Patent applicant responded, stating, inter alia, “the present
invention is directed to this isolated biomaterial compound having elemental
substitutions therein that provide a highly bioresorbable compound that can
be remodeled in vivo and in vitro much like natural bone and can be
provided as powders, pellets, thick coatings, three-dimensional bulk
materials and macroporous structures.” Id. at 304. Petitioner’s reliance on
the Reply Declaration of Dr. Mikos, who attempts to alter the Board’s claim
construction requiring a compound “separated from all other substances”
(Ex. 1134 ¶ 64 (“separated from substantially all other unwanted
substances”)) to justify his opinion, is not entitled to any weight.
Petitioner, moreover, has not provided evidence that quartz is a
“bioresorbable biomaterial” as recited in claim 1. Pet. 32–35 (citing Ex.
1003 ¶¶ 219–224, 313–14, 429–38, 440–450, 609–09, 617; Ex. 1057, 6);
Reply 15 (citing Ex. 1134 ¶¶ 62–67). Petitioner attempts to equate the
quartz substrate with the CaP thin film biomaterial – the “glass/quartz
substrate . . . is part of the CaP product, and serves a core purpose,” (Pet.
Reply 15 (emphasis added) citing Ex. 1134 ¶¶ 62–67) – but a thin-film-on-
quartz CaP “product” is not an “isolated bioresorbable biomaterial
compound.” The quartz acts as a convenient substrate to support the CaP
thin film, but only the CaP thin film is a biomaterial compound. Ex. 1001,
16:54–60, 25:53–57. We find Petitioner has not adduced persuasive
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evidence that the quartz substrate disclosed in Davies is a bioresorbable
biomaterial that should be considered part of the isolated compound.
For the reasons given above, we find that Davies does not disclose an
“isolated bioresorbable biomaterial compound” separated from all other
substances as recited in claim 1 of the ’251 patent. Therefore a
preponderance of the evidence does not support Petitioner’s contention that
Davies anticipates claim 1 of the ’251 patent.
3. Analysis of asserted anticipation of claims 8–13 by Davies
Claims 8–13 of the ’251 patent all depend, ultimately, from claim 1.
We have found, for the reasons given in section II B.2. above, that Davies
does not disclose the “isolated bioresorbable biomaterial compound” recited
in claim 1. Therefore, we determine Petitioner has not provided persuasive
evidence that Davies inherently anticipates dependent claims 8–13 of the
’251 patent.
C. Obviousness of Claim 8 over Davies and Ichitsuka
Petitioner argues the “nanoporous structure” limitation of dependent
claim 8 would have been obvious to a person of ordinary skill in the art,
when Davies is combined with the teachings of Ichitsuka. Pet. 35–37.
Petitioner’s analysis of Ichitsuka focuses on the “nanoporous structure”
limitation and does not address the “isolated bioresorbable biomaterial
compound” limitation of claim 1 that we find lacking in Davies. Id. at 37.
Therefore, we determine Petitioner has not provided persuasive evidence
that the combination of Davies and Ichitsuka renders claim 8 unpatentable
for obviousness under 35 U.S.C. § 103(a).
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D. Anticipation of Claims 1 and 8–13 by Ruys ’93a
Petitioner argues that Ruys ’93a (Ex. 1011) discloses a silicon-
substituted calcium phosphate compound made by a very similar process to
the sol-gel/sintering process described in Examples 1, 2, and 5 of the ’251
patent. Pet. 42–45, 51, 53–54; Pet. Reply. 1–9. Petitioner argues that Ruys
’93a inherently anticipates claims 1 and 8–13 of the ’251 patent under
35 U.S.C. § 102(b). Patent Owner opposes, emphasizing differences
between the Ruys ’93a process and the process described in the ’251 patent.
PO Resp. 8–21, 24–25.
1. Overview of Ruys ’93a
Ruys ’93a, titled “A Feasibility Study of Silicon Doping of
Hydroxylapatite,” discloses an approach to enhancing “the relatively low
bioactivity of hydroxylapatite” (Ex. 1011, Abstract) by forming a silicon-
doped calcium phosphate compound. Ex. 1011, 3 (left column). Ruys ’93a
discloses a two-solution sol-gel process to make finely divided (20 nm)
stoichiometric HA suspended in ethanol.
17
Ex. 1003 ¶ 383 (citing Ex. 1011,
3 (right column)). Ruys ’93a discloses the addition of ethyl silicate to the
suspended HA, then excess water, to form colloidal silica. Id. The
precipitated HA and silica powder are pressed into pellets and sintered at
1100ºC for one hour in air. Id. Ruys ’93a discloses 11 experimental
compositions with varying silicon:HA molar ratios. Ex. 1003 ¶ 385 (citing
Ex. 1011, 3 (right column)).

17
Stoichiometric HA has a Ca:P ratio of 1.67 “consistent with the chemical
formula of HA which includes 10 calcium atoms for every 6 phosphorous
atoms.” Pet. 43 (citing Ex. 1003 ¶ 393).
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Ruys ’93a further discloses analytical data for the sintered material, a
multi-phase, silicon-substituted calcium phosphate compound that includes
TCP as one of “two new apatite phases.” Ex. 1003 ¶ 385 (citing Ex. 1011, 4
(right column)). Ruys ’93a discloses lattice expansion data supporting the
author’s conclusion that “silicon substitution probably occurred . . . at the
phosphorous site since ionic radii restrictions favour this site to the exclusion
of the three alternatives – the calcium, oxygen, and hydroxyl sites.”
Ex. 1011, 4 (right column); Ex. 1003 ¶ 384. Ruys ’93a further states that
“[t]he formation of Ca10(PO4)4 (SiO4)2 shows that silicon substitution into
the phosphorous site can be induced by the sol-gel synthesis method used in
the present work.” Ex. 1011, 4 (right column) (emphasis added). Ruys’93a
also discloses data demonstrating the “apparent porosity” of the compound
as a function of the silicon:HA molar ratios tested.
18
Ex. 1011, 4 (left
column), Fig. 2.
2. Petitioner’s argument and evidence
Petitioner relies on the testimony of Dr. Mikos, who characterizes the
process used in Ruys ’93a as “strikingly similar” to the sol-gel method
described in the ’251 patent and concludes that the Ruys’93a process
“necessarily resulted in products having the same physical, chemical, and
biological properties.” Pet. 43 (citing Ex. 1003 ¶¶ 623–625); Ex. 1003

18
Apparent porosity is a measure of the porosity of a material using a
hydrostatic weighing technique where the material is immersed in water or
kerosene. Ex. 1011, 4 (Fig. 2); see also Ex. 1003 ¶ 134 (“[I]ncomplete
sintering of HA ceramics, which is what was observed in Ruys 1993a, was
known to result in pores.”); Ex. 2026 ¶ 38 (measuring apparent porosity
“does indicate some pores that are accessible to fluid in contact with the
outside of the pellet.”).
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¶¶ 383, 393–394. Petitioner argues that the sintering step disclosed in Ruys
’93a results in an “isolated compound.” Pet. 44 (citing Ex. 1003 ¶¶ 386–87).
Petitioner next points to the statement in Ruys ’93a regarding the creation of
silicon “substituted” HA, and further relies on later work of two of the
named ’251 patent inventors as confirming that the method used in Ruys
’93a would have resulted in silicon-substituted TCP. Pet. 43–44 (citing Ex.
1003 ¶¶ 384, 393–94, 628; Ex. 1119). Petitioner further argues that Ruys
’93a necessarily results in a “microporous structure,” indicated by
incomplete sintering of the silicon-doped CaP compound. Pet. 44–45 (citing
Ex. 1003 ¶¶ 388–394, 625, 632).
3. Patent Owner’s argument and evidence
Patent Owner argues that Ruys ’93a does not disclose inherently
“microporosity” (i.e. “a microporous structure”) of the silicon-doped CaP
compound and that Petitioner has failed to meet its burden of proving Ruys
’93a inherently anticipates claim 1 of the ’251 patent. PO Resp. 8–21.
Patent Owner argues the process disclosed in Ruys ’93a is not equivalent to
the processes disclosed in Example 5 of the ’251 patent (“Preparation of Ca–
P Powder with Silicon as the Introduced Additive”).
19
Id. at 10–16. Patent
Owner urges that, because of “critical” process differences, the Ruys ’93a
process “Do[es] Not Necessarily Result in Interconnected Microporosity.”
Id. at 10 (citing Ex. 2026 ¶ 52); Id. at 14–15 (citing Ex. 2026 ¶¶ 50–52).
Patent Owner further argues the Jarcho prior art reference (Ex. 1010), relied
upon by Dr. Mikos, does not teach that inefficient sintering results
necessarily in microporosity. Id. at 16–21 (citing Ex. 1010 (Jarcho); Ex.

19
Ex. 1001, 29:50–30:12.
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2026 ¶¶ 43, 54, 56; Ex. 2028 (excerpts of Dr. Mikos’s May 6, 2014
deposition transcript)). Patent Owner also attempts to distinguish the
structure of the Ruys ’93a compound from the claimed “microporous
structure,” because the ’251 patent describes “sintering agglomerates
substantially larger than the non-agglomerated particles sintered in Ruys.”
PO Obs. 1–2. Patent Owner does not put forward evidence to rebut
Petitioner’s evidence supporting the Ruys ’93a disclosure of the other
limitations in claim 1 apart from the “microporous structure” limitation. PO
Resp. 8–21.
4. Analysis
a. “isolated bioresorbable biomaterial compound”
With regard to the limitation of claim 1 reciting an “isolated
bioresorbable biomaterial compound comprising calcium, oxygen, and
phosphorous” (Ex. 1001, 33:42–43), Ruys ’93a discloses a CaP compound,
prepared as a powder in the presence of silicon, compressed into pellets, and
sintered at high temperature to form an isolated bioresorbable biomaterial
compound. Ex. 1011, 3 (right column), 4 (right column); Pet. 43–44 (citing
Ex. 1003 ¶¶ 383–87, 393–94, 625). The “isolation” of the silicon-doped
CaP compound, which includes a TCP phase, is accomplished by essentially
the same process steps – precipitating CaP and silica from a sol-gel followed
by sintering at high temperature – that are described in the ’251 patent.
Pet. 43–44 (citing Ex. 1003 ¶¶ 386–87, 393–94, 625, 628); Ex. 1003 ¶ 627.
Patent Owner does not put forward credible evidence to rebut the
aforementioned evidence. PO Resp. 8–21. Petitioner’s unrebutted evidence
is sufficient to persuade us that Ruys ’93a discloses an “isolated
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bioresorbable biomaterial compound comprising calcium, oxygen, and
phosphorous” by a preponderance of the evidence.
b. “substituted with an element Si4+”
Claim 1 further recites “wherein a portion of at least one of said
elements is substituted with an element Si
4+
.” Ex. 1001, 33:43–45. Ruys
’93a first hypothesizes that elemental silicon substitution will occur at the
phosphorous site of the CaP compound (Ex. 1011, 3 (left column)), then
presents analytical data indicating that “silicon substitution probably
occurred . . . at the phosphorous site” (id. at 4 (right column), Figs. 1–3), and
states unequivocally that “silicon substitution into the phosphorous site can
be induced by the sol-gel synthesis method used in the present work.” (id.
(right column)). Pet. 43–44 (citing Ex. 1003 ¶¶ 383–87, 393–94, 625, 628).
Dr. Mikos emphasizes later work of the ’251 patent inventors that “‘firing a
stoichiometric calcium hydroxyapatite precipitate with SiO2 produces Si-
TCP’” (Ex. 1003 ¶ 394), and he concludes that “the methods disclosed in
Ruys 1993a necessarily resulted in multi-phasic materials comprising
silicon-substituted-TCP.” Id. ¶¶ 628–29 (citing Ex. 1119).
Patent Owner does not put forward credible evidence to rebut the
above-cited evidence of Petitioner. PO Resp. 8–21. Petitioner’s unrebutted
evidence is sufficient to persuade us that Ruys ’93a discloses the claim
limitation “wherein a portion of at least one of said elements is substituted
with an element Si
4+
” by a preponderance of the evidence.
c. “microporous structure”
As a preliminary matter, we reject Patent Owner’s claim construction-
based argument (PO Resp. 11–15 (citing Ex. 2026 ¶¶ 45, 46, 51)) that Ruys
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’93a must inherently disclose “interconnected microporosity” in order to
satisfy the wherein clause recitation of “a microporous structure” in claim 1
of the ’251 patent. See section II A.2. above. Further, there is no dispute
that Ruys ’93a discloses a silicon-substituted CaP compound having a
porous structure, graphically demonstrated by the “apparent porosity” curve
in Figure 2 of Ruys ’93a. Ex. 1011, 4 (left column); Pet. 44 (citing Ex. 1003
¶¶ 388–391); Pet. Reply (citing Ex. 1003 ¶ 631; Ex. 2026 ¶¶ 38–39; Ex.
1133, 59:14–18, 242:12–15). The silicon-substituted CaP compound
analyzed in Ruys ’93a demonstrates an apparent porosity as high as 50% of
the material tested. Ex. 1011, 4 (Fig. 2); Tr. 20:7–15. Petitioner and Patent
Owner both recognize, however, that Ruys ’93a does not report pore size.
Pet. Reply 4; Tr. 52:22–24. Therefore, the dispute boils down to whether the
porous structure of the silicon-substituted CaP compound disclosed in Ruys
’93a is inherently “microporous,” i.e. whether the method disclosed in Ruys
’93a would necessarily result in “pore sizes of about 2 microns or less in
diameter,” in accordance with our claim construction. See In re Robertson,
169 F.3d 743, 745 (Fed. Cir. 1999)(“the extrinsic evidence ‘must make clear
that the missing descriptive matter is necessarily present in the thing
described in the reference’”(citation omitted)).
Dr. Mikos explains that some of the known processes for making HA
were understood to result in a microporous structure, and that micropores are
caused by “among other things, incomplete sintering of Ca-P granules,”
which leave open voids in the material. Pet. Reply 4–5 (citing Ex. 1003 ¶ 70
(citing Ex. 1010, 2 (Jarcho); Ex. 1080, 4; Ex. 1039, 9; Ex. 1011, 4; Ex. 1021,
129); Ex. 1003 ¶¶ 388–392, 631; Ex. 1134 ¶¶ 29–34, 36–41). The method
disclosed in Jarcho is the method used in Ruys ’93a to prepare the CaP
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colloidal suspension. Ex. 1011, 3 (right column). Dr. Mikos acknowledges
that “the porosity of the HA (e.g., size and quantity [of pores]) could be
manipulated simply by altering the reaction conditions or adding additives to
the reaction” (Ex. 1003 ¶ 71), as indicated in Jarcho, but he emphasizes that
Ruys ’93a’s two-solution sol-gel and sintering process is “equivalent” to the
two-solution sol-gel and sintering process disclosed in Examples 1 and 5 of
the ’251 patent. Pet. 42–43(citing Ex. 1003 ¶¶ 393–94, 623–625, 632). Dr.
Mikos further reasons that because Ruys ’93a indicates “reduced” or
“retarded” sintering efficiency at very low levels of silicon addition,
resulting in “restraining the green structure of the HAP,” one of skill in the
art would have understood that the silicon-substituted CaP structure was
microporous. Pet. 45 (citing Ex. 1003 ¶¶ 388–391, 625, 632); Pet. Reply 4–
5 (citing Ex. 1003 ¶¶ 70, 388–392, 631; Ex. 1134 ¶¶ 29–34, 36–41; Ex.
1133, 111:3–13, 114:6–116:7, 155:12–156:15; Ex. 1124, 2); Tr. 27:16–29:7
(citing Ex. 1003 ¶¶ 373–74).
Patent Owner argues that the method disclosed in Ruys ’93a differs
from Example 5 of the ’251 patent in at least “two critical ways”: by size of
the HA particles and by sintering temperature. PO Resp. 12–15 (citing Ex.
2026 ¶¶ 46–52).
20
But as to particle size, both the ’251 patent and Ruys
’93a prepare substantially the same nanometer-sized particles in the CaP sol-
gel.

Pet. Reply 2–3 (citing Ex. 1001, 11:61–62 (“The underlying granular

20
Patent Owner also argues that Ruys’93a discloses cold pressing CaP and
silicon powder prior to sintering, which contributes to “a denser product
with reduced porosity.” PO Resp. 14; PO Obs. 2–4. The evidence is clear,
however, that in spite of the asserted process differences between Ruys’93a
and the ’251 patent examples, Ruys’93a results in silicon-substituted CaP
having a porous structure.
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structure was about 5–10 nm in size.”); Ex. 1011, 3 (“Finely divided
(approx. 20 nm) HAP was precipitated as an aqueous suspension . . . .”); Ex.
1133, 129:20–130:2; Ex. 1134 ¶¶ 11–14); see also Ex. 1001, 17:43–45 (“the
underlying structure of the particles is the agglomeration of granules of size
range of approximately 1 to 20 nm . . . .”), and Fig. 6(b) (“note underlying
particle size of 5-10nm”). Patent Owner acknowledged at the oral hearing
that agglomeration of CaP particles, to achieve a preferred size range of 0.2
to 1.0 micron prior to sintering, is not a limitation of the ’251 patent claim
1.
21
Tr. 59:4–61:14. Therefore, Patent Owner’s attempt to distinguish Ruys
’93a from claim 1 based on the Ruys ’93a disclosure of an intention to
prevent agglomeration, is legally irrelevant. Non-agglomerated CaP
particles, such as those disclosed in Ruys ’93a, can still form a “microporous
structure” after sintering, in accordance with our claim construction.

With regard to sintering temperature, Example 5 of the ’251 patent
sinters precipitated CaP and silicon powder at 1000° C for one hour, and
Ruys ’93a sinters precipitated CaP and silicon powder at 1100º C for one
hour. Example 2 of the ’251 patent states that sintering temperatures
between 800º C and 1100º C can be used to produce the claimed compound
having a microporous structure on a “consistent basis.” Pet. Reply 3 (citing
Ex. 1001, 28:66–29:5; Ex. 1133, 135:14–18; Ex. 1134 ¶¶ 15–19). Although
sintering temperature can affect, even eliminate, porosity, the evidence of
record is clear that the method reported in Ruys ’93a results in a porous,
silicon-substituted, CaP biomaterial. Pet. Reply (citing Ex. 1003 ¶¶ 388–
391, 631; Ex. 2026 ¶ 38; Ex. 1133, 59:14–18, 242:12–15); see also Ex.

21
Ex. 1001, 11:52–12:11.
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1133, 111:3–112:5 (“The incomplete sintering results in pores.”). The
sintering temperature of 1100º C disclosed in Ruys ’93a also is within the
temperature range described in the ’251 patent as capable of achieving a
silicon-substituted CaP compound having a microporous structure on a
consistent basis.
22
We are not persuaded by Patent Owner’s argument that
the 1100º C sintering temperature disclosed in Ruys ’93a forecloses the
formation of silicon-substituted CaP as a “microporous structure.”
Petitioner further emphasizes the opinion of Dr. Mikos, supported by
multiple literature references, that the silicon-substituted CaP compound
disclosed in Ruys ’93a would have “necessarily” exhibited a “microporous
structure.” Pet. Reply 4–5 (citing Ex. 1003 ¶¶ 70, 388–392, 631; Ex. 1134
¶¶ 29–34 (literature citations omitted)). Although Dr. Ong testified that he
could not determine whether the pores formed in the Ruys ’93a compound
were “micropores, nanopores, macropores, or a mixture of different pore
sizes” (Ex. 2026 ¶ 40), he acknowledged at his deposition that as a result of
inefficient sintering he would “expect to get a range of pore sizes” and that
“some of them would be nanopores.” Pet. Reply 5 (citing Ex. 1133, 111:3–
13, 114:6–116:7); see also Ex. 1133, 111:14–113:7.
23

22
We note that Table II in Jarcho also discloses the formation of porous
CaP after sintering at 1150º C (sample E–9) and 1200º C (sample F–67). Tr.
88:1–9 (citing Ex. 1010, 5).
23
Petitioner argues that, at page 161 of his deposition transcript, Dr. Ong
admitted the Ruys ’93a method will necessarily result in a range of pore
sizes that includes nanopores, micropores, and possibly macropores. Pet.
Reply 6 (citing Ex. 1133, 161:2–10). Although we do not exclude this
testimony from consideration as requested by Patent Owner in its Motion to
Exclude Evidence (Paper 28), we have carefully weighed Dr. Ong’s cited
deposition testimony in the context of his entire declaration testimony,

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Our claim construction of “microporous structure” includes a range of
pore sizes less than about 2 microns in diameter, without a bottom limit, so
as to include nanometer-sized pores. On the question of pore size, we give
substantial weight to the evidence recited above: (i) the similarity of the
Ruys ’93a process to Examples 1 and 5 of the ’251 patent, (ii) the
preparation of similarly sized CaP particles in the range of 5–20 nanometers,
(iii) the sintering of CaP particles in the presence of silicon at either 1000º C
or 1100º C for one hour to achieve silicon substitution, (iv) the recognition
in the prior art that incomplete sintering results in a microporous structure,
(v) the confirmation of a porous structure from the analytical data in Figure
2 of Ruys ’93a, and (vi) the expectation that incomplete sintering would
result in a range of pore sizes in the Ruys ’93a CaP biomaterial compound,
including at least nanometer-sized pores. Upon full consideration of all the
evidence bearing on this patentability challenge, we find Petitioner’s
assertion that Ruys ’93a inherently discloses a silicon-substituted CaP
compound having a “microporous structure,” as recited in claim 1 of the
’251 patent, is supported by a preponderance of the evidence.
For the reasons given above, we are persuaded by a preponderance of
the evidence that Ruys ’93a anticipates claim 1 of the ’251 patent.
5. Claims 8–13
For the reasons given immediately above, we find the “nanoporous
structure” of claim 8 is disclosed inherently by Ruys ’93a. Pet. 51 (citing

deposition testimony, and other evidence bearing on the issue of pore size.
We note that our Decision rests on substantial evidence adduced by
Petitioner in addition to Dr. Ong’s testimony at page 161 of his deposition
transcript.
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Ex. 1003 ¶¶ 750–51). Petitioner also presents substantial evidence that Ruys
’93a discloses the dependent claim limitations recited in claims 9–13. Pet.
53–54 (citing, inter alia, Ex. 1003 ¶¶ 781–787, 791). Patent Owner does not
argue separately the patentability of claims 8, 9, and 12–13. We are
persuaded by a preponderance of the evidence that claims 8, 9, and 12–13 of
the ’251 patent are anticipated by Ruys ’93a.
Patent Owner contests Petitioner’s assertion that claims 10 and 11 are
anticipated and relies on the theory that the Board must read a limitation
from the specification (i.e., “macroporosity”) into those claims because
macroporosity allegedly is required for CaP biomaterials to exhibit the
properties recited in the claims. PO Resp. 24–25. The ’251 patent itself
undercuts this assertion. First, the ’251 patent states that the thin-film
embodiment—which does not have a macroporous structure—is
bioresorbable, bioactive, and supportive of osteoclast and osteoblast activity,
including progressive replacement of bone material as recited in claims 10
and 11. Pet. Reply 8 (citing Ex. 1001, 4:9–23; Ex. 1003 ¶ 449; Ex. 1134
¶ 70). Second, the assertion that bone remodeling can be achieved only with
macroporous material is contradicted by Patent Owner’s ’992 patent (Ex.
1006), which claims “thin film” material (claims 9 and 18) as a species of
the “biomaterial compound” that supports “osteoclast activity,” “osteoblast
activity,” and “progressive removal and replacement” of bone material
“inherent in the natural bone remodeling process.” Id. at 8–9 (citing Ex.
1006, 33:59–34:29, 35:38–41, 36:9–12). Finally, Dr. Ong and Dr. Mikos
both testified that macroporosity was not necessary for bioactivity and
bioresorption. Id. at 9 (citing Ex. 1133, 282:2–14, 284:11–14; Ex. 1003 ¶
74; Ex. 1134 ¶¶ 68–72).
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For the reasons given above, we are persuaded by a preponderance of
the evidence that Ruys ’93a inherently anticipates claims 10 and 11 of the
’251 patent.
E. Obviousness of Claim 6 over Ruys ’93a and Bioceramics
1. Claim 6
Claim 6 of the ’251 patent depends from claim 1 and requires the
compound to be “formed as a macroporous structure,” with an “open cell
construction” and “interconnected voids having a pore size of approximately
50 to 1000 microns.” Ex. 1001, 33:59–63. The ’251 patent describes using
a silicon-substituted, microporous, calcium phosphate material to form a
“bulk ceramic having a globular microporous structure, an underlying
internal microporous structure and an internal macroporous structure
allowing cells to migrate and function throughout the entire bulk ceramic
unit.” Id. at 27:16–21. The open cell structure of interconnected
macropores, best illustrated in Figure 23, “encourages bone growth and
subsequent remodeling in a system more closely resembling physiological
[in] vivo bone.” Id. at 27:5–8, Fig. 23. Example 8 describes the use of
sintered, microporous, silicon-substituted calcium phosphate powder to form
a slurry in which a piece of open cell (reticulated) polyurethane foam is
immersed. Id. at 30:53–62. The slurry-coated foam is dried and sintered at
1000ºC for one hour, during which time the foam decomposes and is
removed by pyrolysis, leaving a silicon-substituted calcium phosphate
product that replicates the shape and open-cell structure of the foam as a
macroporous structure. Id. at 30:62–67.
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2. Analysis
Petitioner acknowledges Ruys ’93a does not teach the formation of a
macroporous, open-cell structure, but Petitioner argues that formation of
such a structure using Ruys ’93a’s silicon-substituted CaP material would
have been an “obvious design choice” for one skilled in the art in view of the
Bioceramics reference. Pet. 45 (citing Ex. 1003 ¶ 683). Petitioner, relying
on the Declaration of Dr. Mikos, asserts that methods of making a
biomaterial compound having a macroporous structure were conventional
and well known. Id. at 48 (citing Ex. 1003 ¶¶ 147–164, 690); Tr. 34:14–20.
Petitioner notes that Bioceramics was not considered during examination of
the application resulting in the ’251 patent. Id. at 46 (citing Ex. 1003 ¶ 523).
Petitioner emphasizes the Bioceramics disclosure that “[a]n ideal cancellous
bone graft substitute would mimic osteon-evacuated cancellous bone and
have a thin lattice interconnected by pores of 500–600 µm” (Ex. 1021, 110)
and that “[p]orosity and interconnectivity are key determinants of amount
and type of ingrowth” of CaP bone implant material (id. at 116–17). Pet.
46–47 (citing Ex. 1003 ¶¶ 155, 528–530, 685–87). Petitioner asserts that
one of ordinary skill in the art would have been motivated by the teachings
of Bioceramics to form the silicon-substituted CaP compound disclosed in
Ruys ’93a into a macroporous open cell structure with interconnected voids
having pore sizes within the claimed range of 50 to 1000 microns. Id. at 47–
48 (citing Ex. 1003 ¶¶ 689–90).
Patent Owner argues that, even though techniques for forming CaP
compounds into a macroporous structure were well known prior to the ’251
patent’s August 1996 priority date, there was no prior publication of forming
elementally-substituted CaP compounds into a macroporous structure. PO
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Resp. 36–37. Patent Owner further argues Petitioner has failed to prove one
of ordinary skill in the art would have had a reasonable expectation of
success in forming the silicon-substituted CaP powder disclosed in Ruys
’93a into the macroporous structure recited in claim 6. Id. at 37–39. Patent
Owner further relies on asserted secondary considerations in support of
Patent Owner’s argument for the nonobviousness of claim 6. Id. at 27–36,
40–54.
Dr. Ong agreed with Dr. Mikos that interconnected macroporosity
was known to be “critical” to vascularization, bone cell differentiation, and
bone implantation, as stated in the 1993 Bioceramics textbook. Pet. Reply 9
(citing Ex. 1133, 159:16–160:3). Figure 4 in chapter 10 of Bioceramics
illustrates an “[i]dealized microstructure for cancellous bone regeneration”
having “a thin lattice interconnected by pores of 500–600 [microns]” in
diameter. Id.; Ex. 1021, 110–111. Bioceramics, therefore, expressly
discloses the claim 6 recitation of a “macroporous structure” of
“interconnected voids having a pore size of approximately 50 to 1000
microns,” and Bioceramics provides sound physiological reasons for
forming a CaP biomaterial compound into a macroporous structure.
Dr. Ong further agreed that Bioceramics teaches well-known methods
for preparing open-cell macroporous structures from CaP biomaterials and
that the ’251 patent, Example 8, describes similar well-known techniques.
Pet. Reply 9–10 (citing Ex. 1133, 226:7–233:18). Dr. Karin Hing, a
research scientist for ApaTech and currently Senior Lecturer in Biomaterials
at Queen Mary University of London, provides unrebutted testimony that
“[t]he desirability of incorporating interconnected macropores in calcium
phosphate bone graft substitute materials was well known in the 1990’s.”
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Ex. 1136 ¶ 8. Dr. Hing’s further opinion, that “the benefits of
interconnected macroporosity and prior methods for incorporating
macroporosity were known well before the filing of [the ’251] patent” (id.
¶ 23), is supported by extensive corroborative evidence. Id. ¶¶ 9–20.
3. Secondary considerations
Patent Owner argues that objective indicia, including long-felt but
unmet need, the failure of Petitioner to arrive at the claimed invention until
many years later, the length of intervening time between the prior art and the
claimed invention, unexpected results, wide acclaim in the industry, and
commercial success (PO Resp. 40–54), “contravenes and eliminates any
hindsight argument that the claimed invention of claim 6 was obvious.” PO
Resp. 8. In support, Patent Owner relies on, inter alia, the Declaration of
Dr. Ong.
Patent Owner cites evidence of the success of Patent Owner’s bone
graft material, sold under the trade name Skelite, and Petitioner’s bone graft
material, sold under the trade name Actifuse, in support of Patent Owner’s
argument. Id. at 42–45. Patent Owner states that Skelite

is a “calcium-
phosphate bone material that contains silicon substitution” and “result[s] in
resorption by osteoclasts and deposition of new bone by osteoblasts
according to the natural course of bone remodeling, on the basis of its
interconnected micro-and macroporosity.” Id. at 43 (citing Ex. 1001, 23:13–
18; Ex. 2030, 2; Ex. 2026 ¶ 83). Patent Owner states that Actifuse is a
“silicon substituted calcium-phosphate bone material having properties that
. . . result in resorption by osteoclasts and deposition of new bone by
osteoblasts according to the natural course of bone remodeling on the basis
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of its interconnected micro-and macroporosity.” Id. at 44 (citing Ex. 2026 ¶
85; Ex. 2032, 1).
It is not sufficient, however, for Patent Owner to establish that a
product is within the scope of a claim. Patent Owner must establish a causal
relationship, a “nexus,” between the asserted secondary consideration (e.g.,
long-felt need or commercial success of a product) and the unique
characteristics of the claimed invention. Merck & Co., Inc. v. Teva Pharm.
USA, Inc., 395 F.3d 1364, 1376 (Fed. Cir. 2005). Objective evidence of
non-obviousness must be tied to the novel elements of the claim at issue,
otherwise the evidence will not suffice to establish the required nexus to the
claimed invention. In re Kao, 639 F.3d 1057, 1068 (Fed. Cir. 2011).
a. Long-Felt but Unmet Need
Patent Owner contends that the claimed invention met a long-felt but
unsolved need. PO Resp. 45. Patent Owner contends that, prior to the ’251
patent priority date, only autologous bone could provide biocompatibility
and bioresorption to match that of natural bone rebuilding, but autologous
bone had the disadvantage of requiring at least two surgical interventions
(one to harvest and one to implant). Id. at 45–46 (citing Ex. 2026 ¶¶ 86–87;
Ex. 2034, 1)). Patent Owner further argues that Petitioner has acknowledged
the long-felt need and prior failure of others. Id. at 46 (citing Ex. 2001, 2).
Patent Owner does not explain how a nexus exists between the
asserted long-felt need for a synthetic bone graft material to replace
autologous bone and the features of claim 6. In particular, Patent Owner
does not tie the effectiveness of Skelite and/or Actifuse to any asserted
novelty of the claimed macroporous structure. For example, Dr. Ong
admitted he did not perform a comparative analysis of Actifuse or Skelite
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with autologous bone grafts or other macroporous HA bone replacement
biomaterials that were available on the market or reported in the prior art.
Pet. Reply 13 (citing Ex. 1133, 248:22–250:17, 253:7–258:21; Ex. 2031, 5;
Ex. 2026 ¶ 83). Consequently, we are not persuaded by Patent Owner’s
contentions in relation to long-felt but unmet need.
b. Failure of ApaTech to arrive at the invention until many
years later
Patent Owner argues that Petitioner ApaTech’s “prolonged path to
discovery” regarding Actifuse reflects the non-obviousness of claim 6. PO
Resp. 46; see also id. at 27–33 (discussing ApaTech’s “development
history” of silicon-substituted CaP formed into a macroporous structure).
Patent Owner asserts it was not until October 1998 – more than two years
after the ’251 patent’s August 1996 priority date – that Petitioner’s team
filed a patent application directed to a process of forming CaP biomaterials
into a macroporous structure. Id. at 46–47 (citing Ex. 2024, 2:61, 5:10;
2035, 3). Patent Owner argues that Petitioner’s own actions during the
relevant time period undermine Petitioner’s current assertion that claim 6
would have been obvious over Ruys ’93a and Bioceramics. Id. at 47.
To the extent Patent Owner relies on the Declaration of Dr. Ong to
establish ApaTech’s development timeline, Dr. Ong admitted he did not
know when the ApaTech researchers first formed the idea of “introducing
macroporosity into their calcium phosphate material.” Pet. Reply 12 (citing
Ex. 1133, 213:10–14). Dr. Ong also admitted the ApaTech patent (Ex.
2024) on which he relied in his Declaration (i) recognizes that the concept of
interconnected macropores was known, and (ii) is directed to a process for
making a “specific macroporous structure.” Pet. Reply 12 (citing Ex. 1133,
217:14–218:2, 219:7–11). As noted earlier, Dr. Hing testified that the
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benefits of interconnected macroporosity and methods for incorporating
macroporosity were known well before the August 1996 priority filing date
of the ’251 patent. Ex. 1136 ¶¶ 8–20. Dr. Hing further testified that the
ApaTech patent referenced in Dr. Ong’s Declaration (Ex. 2024) is directed
to a foamed ceramic technique intended to be “used commercially, for
reproducibly introducing macroporosity into any bioceramic material.” Id.
¶¶ 21–22. In short, Patent Owner conflates Petitioner’s efforts to develop a
particular technique for reliably forming a CaP biomaterial into a
macroporous structure, with the more general claim 6 limitation of a
compound “formed as a macroporous structure.” Therefore, the evidence of
record does not support Patent Owner’s argument that Petitioner’s asserted
failure to arrive at its bone replacement product was due to the non-
obviousness of forming a microporous CaP biomaterial into a macroporous
structure.
c. Unexpected results, industry acclaim, and commercial
success
Patent Owner contends that the claimed silicon-substituted
microporous CaP compound formed into a macroporous structure “was, very
surprisingly, able to greatly exceed the performance of porous HAP as
evidenced by studies conducted using both Skelite and Actifuse, and
according to studies conducted on Actifuse, was able to meet or exceed the
performance of the gold-standard autologous bone.” PO Resp. 47–48 (citing
Ex. 2026 ¶ 88). For example, Patent Owner contends that the osteoclast
resorption rate of Skelite greatly exceeded that of HA. Id. at 48 (citing Ex.
2036, 1; Ex. 2026 ¶ 90). Patent Owner further contends that Actifuse “was
biomechanically, radiographically, and histologically equivalent to autograft
in the ovine model.” Id. (citing Ex. 2034, 308–09; Ex.2035, 5–6; Ex. 2026 ¶
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88). Patent Owner also contends that Actifuse “promote[d] rapid bone
formation and an elevated volume of bone ingrowth compared with
traditional calcium phosphates of similar structure.” Id. at 48–49 (citing Ex.
2037, 3–4; Ex. 2026 ¶ 89).
Patent Owner fails to explain how the asserted unexpected results are
attributable to the features recited in claim 6. More particularly, Patent
Owner does not provide comparative tests or analysis of the claimed
invention relative to prior art silicon-substituted CaP biomaterials, such as
those disclosed in Ruys ’93a, to establish that formation of the silicon-
substituted biomaterial into a macroporous structure is the reason for the
asserted unexpected results. Petitioner contends that Patent Owner could
have compared Skelite or Actifuse “to numerous bone substitute products on
the market in the mid-1990s, such as Endobon and Pro Osteon” as opposed
to the “autologous bone and generic hydroxyapatite material [Patent Owner]
does compare.” Pet. Reply 13 (citing Ex. 1133, 248:22–250:17, 253:7–
258:1; Ex. 2031, 5; Ex. 2026 ¶ 83). Having considered the evidence
presented, we are not persuaded that Patent Owner has shown a sufficient
nexus between the asserted unexpected results of Skelite or Actifuse and any
novel aspect of forming those silicon-substituted CaP biomaterials into a
macroporous structure.
We reach the same conclusion with respect to Patent Owner’s
assertions of industry acclaim and commercial success. The evidence cited
by Patent Owner suggests the benefits from Skelite and Actifuse are
attributable to silicon substitution, previously disclosed in Ruys ’93a, and
the use of the claimed macroporous “scaffolds” to promote bone growth.
PO Resp. 50–51 (citing Ex. 2039, 3 (“we have uncovered the role of trace
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elements that are found in normal bone . . . [and] if you incorporate these
elements in synthetic bone graft scaffolds, you actually get a unique
biological effect”)); Ex. 2040, 4 (“[T]he company has successfully received
FDA approval for clinical use of Skelite
TM
scaffolds.”); 2041;
24
Ex. 2043, 1–
2; Ex. 2044.
25
The cited evidence, however, must be read in the context of
the Bioceramics disclosure of an idealized cancellous bone graft substitute
having an interconnected macroporous structure (Ex. 1021, 110–11) and Dr.
Hing’s unrebutted testimony regarding the known benefits of interconnected
macroporosity and prior art methods for incorporating macroporosity (Ex.
1136 ¶¶ 9–20), which was confirmed by Dr. Ong (Ex. 1133, 226:7–233:18).
On balance, we are not persuaded that Patent Owner’s industry acclaim
evidence is sufficient to outweigh Petitioner’s strong evidence of the
obviousness of claim 6.
Patent Owner argues that in 2009, after only four years on the market,
annual sales of Actifuse were $90 million, and in March 2010, Baxter

24
“Current products range from powders and granules, which are designed
to fill small, irregular bone voids at common fracture sites, to large porous
synthetic scaffolds that can repair problems such as badly damaged limbs or
collapsing spines . . . . Because it can be manufactured at low cost in various
function-specific configurations, Skelite satisfies critical needs in a variety
of medical and biotechnology applications.” Ex. 2041, 7.
25
“ApaTech has introduced a novel silicate substituted calcium phosphate
bone graft material, Actifuse
TM
globally. The company believes that
Actifuse is the first of a new class of synthetic bone graft material that
combines osseo-conductive and osseo-stimulatory activities. Actifuse has
been shown to accelerate the rate and quality of bone formation and is
available as a range of granule and microgranule formulations . . . combining
the biological benefits of Actifuse scaffold with placement and mouldability
benefits.” Ex. 2044, 1.
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International acquired ApaTech for $330 million specifically to acquire
Actifuse. PO Resp. 53 (citing Ex. 2049, 1; Ex. 2001, 6). Gross sales
figures, in the absence of evidence as to market share or what sales would
normally be expected in the market, do not support an inference that the
sales represent a substantial share of any definable market. Cable Elec.
Prod., Inc. v. Genmark, Inc., 770 F.2d 1015, 1027 (Fed. Cir. 1985) (reversed
on other grounds); see also Pet. Reply 14 (stating that “because the sales
figures for Actifuse fail to provide any analysis of relative market share, they
are fatally defective”) (citing In re Applied Materials, Inc., 692 F.3d 1289,
1300 (Fed. Cir. 2012)). Based on the record before us, we find Patent
Owner’s evidence of nexus in relation to commercial success to be tenuous,
and we do not accord the cited evidence of commercial success significant
weight.
4. Conclusion
In sum, the evidence establishes that one of ordinary skill in the art of
bone implant materials, prior to the ’251 patent priority date, would have
had sound reasons to form the silicon-substituted CaP compound of
Ruys’93a into a “macroporous structure” having “an open cell construction
with interconnected voids having a pore size of approximately 50 to 1000
microns,” with every expectation of success.
Ruys ’93a, moreover, does not teach away from forming a silicon-
substituted CaP compound into a macroporous structure of interconnected
voids, as asserted by Patent Owner. PO Resp. 33–35. It is true that Ruys
’93a does not acknowledge or address macroporosity, and Ruys ’93a does
focus on the potential biological impact of silicon doping rather than
“porosity control.” Id. (citing Ex. 1011, 3; Ex. 2026 ¶¶ 77–79). By the
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same token, Ruys ’93a concludes that the reported silicon doping
experiments “have established the suitability of silicon-doped HAP for
clinical trials,” a clear indication of the potential use of silicon-doped CaP
compounds for the types of well-known biomaterial applications disclosed in
Bioceramics. Pet. Reply 10–11 (citing, inter alia, Ex. 1134 ¶¶ 78–85).
Therefore, we conclude that Petitioner has established the obviousness
of claim 6 over the combination of Ruys ’93a and Bioceramics by a
preponderance of the evidence.
F. Motions to Exclude Evidence
The party moving to exclude evidence bears the burden of proof to
establish that it is entitled to the relief requested, namely that the material
sought to be excluded is inadmissible under the Federal Rules of Evidence.
See 37 C.F.R. §§ 42.20(c), 42.62(a).
Petitioner seeks to exclude Exhibits 2003 and 2039–2041, on which
Patent Owner relies in support of asserted secondary considerations of
nonobviousness of claim 6. Pet. Mot. Excl. Petitioner objects to the
timeline of Exhibit 2003 for lack of authentication and foundation. Id. at 2–
3. Exhibit 2003 is a demonstrative timeline of ApaTech patent filings from
1996 to 2008. Petitioner objects to Exhibits 2039–2041 for lack of
authentication and hearsay, because each exhibit is a website printout
regarding Patent Owner’s Skelite product. Id. at 4–5. We need not reach the
merits of Petitioner’s Motion to Exclude, because even upon full
consideration of this evidence, we determine that Petitioner has shown the
obviousness of claim 6 by a preponderance of the evidence. Accordingly,
Petitioner’s motion to exclude is dismissed as moot.
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Patent Owner seeks to exclude paragraphs 20, 23–27, 35, 96–102, and
125 of Exhibit 1134 (reply testimony of Dr. Mikos) under Fed. R. Evid. 401,
402, and/or 403. PO Mot. Excl., 1–5. Patent Owner further seeks to exclude
paragraphs 28, 35, 108–140 of Exhibit 1134 under Fed. R. Evid. 702 and
paragraphs 21, 62–67 under 37 C.F.R. § 42.23. Id. at 5–10. We do not rely
on any of the identified paragraphs in Exhibit 1134 as evidence in support of
our Decision. Therefore, sections I–III of Patent Owner’s motion to exclude
are dismissed as moot.
In section IV of its motion, Patent Owner seeks to exclude certain
deposition testimony of Dr. Ong and related reply testimony of Dr. Mikos,
bearing on the issue of whether Ruys ’93a inherently discloses a
“microporous structure.” Id. at 10–14. The particular testimony in question
appears at page 161 of Dr. Ong’s deposition transcript (Ex. 1133) and is
referenced in paragraphs 41, 46, and 48 of the Reply Declaration of Dr.
Mikos (Ex. 1134). Id. at 10. Patent Owner argues the asserted admission of
inherency is not consistent with Dr. Ong’s earlier deposition testimony, is
the result of opposing counsel harassing the witness, and amounts to
cumulative testimony. As indicated previously, we do not rely on the
identified testimony of Dr. Ong as an admission that Ruys ’93a
“necessarily” discloses a microporous structure. Having been alerted to the
dispute by Patent Owner, through its motion and again during the oral
hearing, we have taken great care to weigh all of Dr. Ong’s testimony on the
issue in context and in view of the additional evidence adduced by both
parties in this dispute. Therefore, we are not persuaded of any undue
prejudice, confusion, or misleading result derived from our consideration of
the testimony. We do not find reason to exclude the testimony in question.
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For the reasons given above, section IV of Patent Owner’s motion to
exclude is denied.
G. Motion for Observation
Patent Owner’s observations are directed to the cross-examination
testimony of Dr. Mikos (Ex. 2055), who was deposed after Petitioner filed
its Reply. We have considered Patent Owner’s observations, and
Petitioner’s response, regarding the dispute over whether Ruys ’93a
discloses a “microporous structure” (PO Obs. 1–3), ApaTech’s development
history (id. at 4), and the assertion of “misleading” positions by Petitioner
and Dr. Mikos (id. at 4–5). We have accorded the testimony the appropriate
weight, but Patent Owner’s observations do not change our findings or
conclusions.
III. CONCLUSION
We determine Petitioner has established by a preponderance of the
evidence that claims 1 and 8–13 of the ’251 patent are unpatentable as
anticipated by Ruys ’93a under 35 U.S.C. § 102(b). We also determine
Petitioner has established by a preponderance of the evidence that claim 6 is
unpatentable as obvious over Ruys’93a and Bioceramics under 35 U.S.C.
§ 103(a).
IV. ORDER
In consideration of the foregoing, it is hereby:
ORDERED that claims 1, 6, and 8–13 of the ’251 patent have been
shown by a preponderance of the evidence to be unpatentable;
FURTHER ORDERED that Petitioner’s Motion to Exclude is
dismissed as moot; and
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FURTHER ORDERED that sections I–III of Patent Owner’s Motion
to Exclude are dismissed as moot; and
FURTHER ORDERED that section IV of Patent Owner’s Motion to
Exclude is denied.
This is a final written decision. Parties to the proceeding seeking
judicial review of the decision must comply with the notice and service
requirements of 37 C.F.R. § 90.2.

FOR PETITONER:
Jeffrey P. Kushan, Lead Counsel
Peter S. Choi, Back-up Counsel
SIDLEY AUSTIN LLP
jkushan@sidley.com
peter.choi@sidley.com

FOR PATENT OWNER:

Keith A. Rutherford, Lead Counsel
Marilyn Huston, Back-up Counsel
James Hall, Back-up Counsel
WONG CABELLO LUTSCH RUTHERFORD & BRUCCULERI, L.L.P.
krutherford@counselip.com
MBIPR@counselip.com
jhall@counselip.com

Andre J. Bahou, Back-up Counsel
MILLENIUM BIOLOGIX, LLC
aj.bahou@milleniumbiologix.com