Ex Parte 6746773 et al

Patent Trial and Appeal Board

Nov 19, 2015

95000567 (P.T.A.B. Nov. 19, 2015)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
95/000,567 08/23/2010 6746773 01035.0069-00000 1682
45511 7590 11/19/2015
Baker & Hostetler LLP
CIRA CENTRE, 12TH FLOOR
2929 ARCH STREET
PHILADELPHIA, PA 19104-2891
EXAMINER
JONES, DWAYNE C
ART UNIT PAPER NUMBER
3991
MAIL DATE DELIVERY MODE
11/19/2015 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

ABBOTT LABORATORIES
Requester and Respondent

v.

Patent of
ETHICON, INC., A JOHNSON & JOHNSON CO., and WYETH, A PFIZER CO.
Patent Owners and Appellants
____________

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Patent 6,746,773 B2
Technology Center 3900
____________

Before ROMULO H. DELMENDO, RICHARD M. LEBOVITZ, and
JEFFREY B. ROBERTSON, Administrative Patent Judges.

LEBOVITZ, Administrative Patent Judge.

DECISION ON APPEAL
This is a decision on the appeal by Patent Owners (collectively “Patent
Owner” or “Appellant”) from the Patent Examiner’s final rejection of claims 4 and
6–9 as obvious under 35 U.S.C. § 103 in the above-identified inter partes
reexaminations of United States Patent 6,746,773 B2. The Board’s jurisdiction for
this appeal is under 35 U.S.C. §§ 6(b), 134, and 315 (pre-AIA). We affirm but, for
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the reasons given below, designate our affirmance as including new grounds of
rejection.
BACKGROUND
The patent in dispute in this appeal is US 6,746,773 B2 (“the ’773 patent”)
which issued June 8, 2004. The real parties in interest and assignees are Ethicon
Inc. (Reel 036781, Frame 0657) and Wyeth LLC (Reel 29073, Frame 326) (“Patent
Owner”).
A request for inter partes reexamination of the ’773 patent was filed Aug.
23, 2010 by Abbott Laboratories (“Requester”) under 35 U.S.C. §§ 311–318 and
37 C.F.R. §§ 1.902–1.997. Requester filed a paper on October 6, 2015
withdrawing from the reexamination proceeding.
An oral hearing was held October 21, 2015 with only Patent Owner in
attendance. A transcript of the hearing will be entered into the record.
This reexamination is related to the merged inter partes reexaminations
Control Nos. 95/000,542 and 95/000,552 (hereinafter “the merged
reexamination”), which involve a patent that claims priority from a patent
application from which the ’773 patent claims priority. The Examiner’s rejection
of all claims in the merged reexamination was appealed to the PTAB and a
decision (Appeal Number 2014-008135) was mailed February 27, 2015 affirming
the Examiner. Patent Owner appealed the decision to the U.S Court of Appeals for
the Federal Circuit.
Patent Owner states the ’773 patent is subject to litigation in the District of
New Jersey court, but the litigations are stayed pending the outcome of the
reexamination. Appeal Br. 1. Patent Owner also has advised the PTAB of Cordis
Corporation v. Rea, Civil Action No. 1:12-cv-00075-AJD-IDD (E.D. Va.), which
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relates to the availability of subpoenas in this reexamination, as well as the two
aforementioned merged reexaminations. Id.
The claimed subject matter of the ’773 patent relates to an “implantable
medical device comprising a metallic stent and a biocompatible film coating.”
Claim 4. The coating comprises “a polyfluoro copolymer comprising about 85
weight percent of polymerized residue of vinylidenefluoride [VDF] and about 15
weight percent of polymerized residue of hexafluoropropylene [HFP].” Id. The
coating is referred to a “VDF-HFP copolymer.” Right of Appeal Notice (“RAN”)
12. The VDF-HFP copolymer is “mixed with effective amounts of a therapeutic
and/or pharmaceutical agent.” Claim 4.
According to the ’773 patent, stents are “commonly used in translumen[]al
procedures such as angioplasty to restore adequate blood flow to the heart and
other organs.” ’773 patent, col. 1, ll. 18–20. The patent teaches that “deployment
of stents may stimulate foreign body reactions thereto that result in thrombosis or
restenosis.” Id. at col. 1, ll. 20–22. “To avoid these complications, a variety of
stent coatings and compositions have been proposed to reduce the incidence of
these complications.” Id. at col. 1, 23–25. The ’773 patent teaches that the
coatings “may be capable themselves of reducing the stimulus the stent provides to
the injured lumen wall, thus reducing the tendency towards thrombosis or
restenosis.” Id. at col. 1, ll. 25–28. The patent also teaches that “the coating may
deliver a pharmaceutical/therapeutic agent or drug to the lumen that reduces
smooth muscle tissue proliferation or restenosis.” Id. at col. 1, ll. 28–31. The
patent discloses that polytetrafluoroethylene (PTFE) homopolymers “have been
used as implants for many years.” Id. at col. 1, ll. 45–47. The ’773 patent
describes, “implantable medical devices, e.g. stents, coated with a film of the
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polyfluoro polymeric coating in amounts effective to reduce thrombosis and/or
restenosis when such stents are used in, e.g. angioplasty procedures.” Id. at col. 2,
ll. 41–45.
CLAIM 4
Independent claim 4 is the only independent claims involved in the appeal.
Claim 4 reads as follows: (abbreviations within brackets added):
4. An implantable medical device comprising a metallic stent and a
biocompatible film coating effective to provide an inert surface to be
in contact with body tissue of a mammal upon implantation of said
device in said mammal, said film coating comprising a polyfluoro
copolymer comprising about 85 weight percent of polymerized
residue of vinylidenefluoride [VDF] and about 15 weight percent of
polymerized residue of hexafluoropropylene [HFP] mixed with
effective amounts of a therapeutic and/or pharmaceutical agent.

REJECTIONS
Pending claims 4 and 6–9 stand rejected by the Examiner over nine different
combinations of publications. RAN 4–52; Appeal Br. 3–4. Each of the rejections
of independent claim 4 is based on substantially the same factual underpinnings,
but relies on different publications for the same set of facts. Rather than
addressing each ground separately, Patent Owner has focused its arguments on the
factual basis of the rejections, grouping their arguments together for the various
grounds of rejection of the independent claims. The rejections of the dependent
claims were not argued separately.
Because the rejections were argued together, we have focused on the
rejection based on Tuch, 1 Tu,2 and Lo3 (as evidenced by Dorland4) and have not

1 Tuch, US 5,824,048 issued Oct. 20, 1998.
2 Tu et al. (“Tu”), US 4,816,339 issued Mar. 28, 1989.
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reached rejections 2–9, although as recognized by Patent Owner, similar rationale
would apply to the other rejections. In addition to these publications, we also have
relied upon the teachings in Le Morel,5 a publication cited in the current
reexamination (submitted on August 23, 2010) as well as in the related merged
reexamination and thus both the Patent Owner and Requester have been aware of
this publications during this present inter partes reexamination. We also further
cite Lilenfeld.6 Lilenfeld is of record in the related merged reexamination.
In addition to the prior art publications, the following declarations have been
relied upon as evidence:
First Declaration by Antonios G. Mikos, Ph.D. (“First Mikos Decl.”) dated
May 13, 2011. Dr. Mikos was a Professor of Bioengineering and Chemical and
Biomolecular Engineering in the Departments of Bioengineering and Chemical and
Biomolecular Engineering at Rice University at the time the Declaration was
executed. First Mikos Decl. ¶ 1. Dr. Mikos testified that he has expertise in the
synthesis, fabrication, and application of biomaterials, specifically polymers, for
medical applications, including cardiovascular applications. Id. ¶ 3. Dr. Mikos
testified on behalf of the Patent Owner.
Second Declaration by Antonios G. Mikos, Ph.D (“Second Mikos Decl.”)
dated October 24, 2012.
To be clear, the new ground of rejection is as follows.
Claims 4 and 6–9 stand rejected under 35 U.S.C. § 103(a) as obvious in view
of Tuch, Tu, Lo, Le Morel, and Lilenfeld. As explained in more detail below,

3 Lo, US 3,178,399 issued Apr. 13, 1965.
4 Dorland's Illustrated Medical Dictionary, 28th Edition, (1994), p. 455
5 Le Morel et al. (“Le Morel”), FR 2,785,812 published Nov. 16, 1998.
6 U.S. Patent 4,564,013, issued Jan. 14, 1986.
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Lilenfeld is newly cited for suggesting the claimed VDF-HFP polymer in the
recited ratio and Le Morel is newly cited for teaching a VDF-HFP polymer on
stent. We consider Lo as more a part of the scope and content of the prior art or
“to demonstrate the knowledge and perspective of one of ordinary skill in the art,”
and buttresses the teachings in Tu, Le Morel, and Lilenfeld. Randall Mfg. v. Rea,
733 F.3d 1355, 1362 (Fed. Cir. 2013).
Dorland is not relied upon since this reference was cited for teaching a
specific well-known pharmaceutical agent which is not recited in any of the
pending claims.

REJECTION BASED ON TUCH, TU, LO, AND DORLAND
A. Rejection
The Examiner found that Tuch describes “a balloon-expandable stent for
intraluminal implantation having a polymer coating and a therapeutic substance
with the polymer on the body of the stent.” RAN 10. The Examiner found that
Tuch lists various therapeutic agents to be combined with the polymer, including a
dexamethasone-coated stent which reduces the amount of cell proliferation
associated with arterial injury and restenosis. Id. The Examiner also found that
Tuch teaches, “that the polymeric layer may be formed of polyvinylidene fluoride
(VDF), which is a crystalline homopolymer ([Tuch at] column 5, lines 40-41).” Id.
The Examiner acknowledged that Tuch does not disclose that the polymer is
comprised of a copolymer of vinylidene fluoride (VDF) and hexafluoropropylene
(HFP) having a weight percent ratio of 85:15 as recited in independent claim 4. Id.
at 11. However, the Examiner determined that it would have been obvious to one
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of ordinary skill in the art to have employed VDF-HFP in the claimed amounts
based on the teachings of Tu and Lo.
Specifically, the Examiner found that “Tu discloses a medical implant that
preferably employs the copolymer of VDF-HFP, which promotes elasticity and
strength for the implanted device along with a therapeutic agent.” Id. at 13. The
Examiner stated that Tu teaches “that the VDF-HFP elastomer provides a
hydrophilic tissue-compatible porous layer, which promotes the elasticity and
strength for the device (column 3, lines 61-64).” Id. at 16. Based on this teaching,
the Examiner concluded that it would have been obvious to “to substitute the VDF
homopolymer of Tuch for the copolymer of VDF-HFP because Tu uses this
copolymer to coat medical implant devices.” Id. Furthermore, the Examiner
reasoned that the skilled worker would have had reason to make the substitution
“in order to make an implantable device that provides a hydrophilic tissue
compatible porous layer, which promotes the elasticity and strength of a stent
while administering a controlled release drug with a reasonable expectation of
success.” Id. at 27.
With respect to the claimed ratio of 85:15 of VDF to HFP, the Examiner
found that Lo teaches amounts which fall within the recited amounts. Id. at 12.
The Examiner determined it would have been obvious to have used this ratio
because Lo teaches that the copolymers in such amounts “are extremely useful
because of their unique combination of high tensile strength and reversible
elongation properties and are especially suitable as durable, flexible coatings for
application to various fabric surfaces.” Lo, col. 10, ll. 24–28.

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B. Issues
Patent Owner contends that the Examiner did not identify a reason as to why
one of “ordinary skill seeking to identify a suitable coating for a metallic stent
would have consulted references directed to other types of medical devices, such as
polymeric vascular grafts” as described in Tu. Appeal Br. 14. Furthermore, Patent
Owner argues that the Examiner did not identify any teaching in the prior art
regarding the use of any VDF/HFP copolymer as a carrier for drug delivery.
Patent Owner states “Tu makes a passing reference to placing a therapeutic agent
in an optional outer elastomer layer, but does not connect this teaching to any of
the different polymers that may be used in the outer elastomer layer.” Id. at 22.
Patent Owner also argues that the Examiner erred because one of ordinary skill in
the art would not have consulted Lo, a patent directed to industrial uses of the
VDF-HFP polymer. Id. at 21. We address Patent Owner’s arguments below.

C. Did the Examiner fail to identify a reason why one of ordinary skill in the art
would have sought alternative polymers to those described in Tuch?
Patent Owner contends that the Examiner did not identify a reason as to why
one of ordinary skill in the art would have sought alternative polymers to those
already disclosed by Tuch. Appeal Br. 12. Patent Owner argues that Tuch does
not identify a problem with any of the polymers disclosed in it that would have led
one of ordinary skill in the art to consult other prior art references for additional
polymer types. Id. at 13.
Patent Owner’s arguments do not convince us that the Examiner erred in the
overall conclusion of obviousness. The following findings of fact are pertinent:
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FF1. At column 5, lines 14–53, Tuch discloses a list of biostable or
bioabsorbable polymers useful for coating its stent.
FF2. Tuch states the “polymer chosen must be a polymer that is
biocompatible and minimizes irritation to the vessel wall when the stent is
implanted.” Tuch, col. 5, ll. 13–15.
FF3. Tuch’s list includes generic polymer classes that encompass unnamed
species. For example, the list names “acrylic polymers and copolymers,” “vinyl
halide polymers and copolymers,” “polyvinyl ethers,” “polyvinylidene halides,”
and “polyvinyl aromatics,” each of which represents a genus with unidentified
species. Id. at col. 5, ll. 14–53.
FF4. Tuch’s list of polymers is not exhaustive in view of Tuch’s disclosure
that the polymer classes can include specific species (“such as”) without naming
all the species, e.g., “vinyl halide polymers and copolymers, such as polyvinyl
chloride” and “polyvinylidene halides, such as polyvinylidene fluoride and
polyvinylidene chloride.” Id. at col. 5, ll. 38–42.
FF5. Tuch uses the transitional phrase “such as” in prefacing the list of
biostable polymers and in reciting specific examples of the broader classes,
indicating that Tuch did not confine the skilled worker to the explicit list, but
contemplated polymers outside of it. (“Also, biostable polymers with a relatively
low chronic tissue response such as . . . and other polymers could also be used if
they can be dissolved and cured or polymerized on the stent such as . . . vinyl
halide polymers and copolymers, such as . . . ” Id. at col. 5, ll. 33–39).

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Analysis
The expansive disclosure in Tuch (FF1–FF5) provides a logical and fact-
based reason for one ordinary skill in the art to have sought alternative polymers
from those which are described by Tuch and possess the characteristics required by
Tuch. In re Leshin, 277 F.2d 197, 199 (CCPA 1960) (“Mere selection of known
plastics to make a container-dispenser of a type made of plastics prior to the
invention, the selection of the plastics being on the basis of suitability for the
intended use, would be entirely obvious.”).
Moreover, there is a “normal desire of scientists or artisans to improve upon
what is already generally known.” In re Peterson, 315 F.3d 1325, 1329–1330
(Fed. Cir. 2003). That one of ordinary skill in the art would seek alternative
polymers to those disclosed in Tuch is not an indicia of nonobviousness, but rather
reflects the normal process of scientific innovation. “A person of ordinary skill is
also a person of ordinary creativity, not an automaton.” KSR Int’l Co. v. Teleflex
Inc., 550 U.S. 398, 421 (2007). Such a person would not have been woodenly
confined to the lists of named polymers described in Tuch, absent a teaching that
such named polymers are the only polymers that would work on Tuch’s stent,
because the skilled worker would look to improve Tuch by applying suitable
alternative polymers to the stent material or to investigate and confirm the actual
scope and content of Tuch.
To support their position about the non-obviousness of using polymers other
than those disclosed in Tuch, Patent Owner cites Kinetic Concepts, Inc. v. Smith &
Nephew, Inc., 688 F.3d 1342, 1370–71 (Fed. Cir. 2012).
As in Kinetic Concepts, Inc. 688 F.3d at 1369, a case in which the
Federal Circuit overturned a prior finding of obviousness, the record
here “is devoid of any reason someone would combine [the cited]
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references.” Where, as here, each device that the references describe
“independently operates effectively,” a person having ordinary skill in
the art “would have no reason” to combine the references’ respective
teachings. Id.
Appeal Br. 13–14.
In Kinetic, the issue was whether to combine publications which “both . . .
independently accomplish similar functions, namely, draining fluids.” Kinetic
Concepts, Inc., 688 F.3d at 1369. One set of publications involved negative
pressure to drain wounds. Id. at 1362–1363. The other set of publications
disclosed a different type of wound drainage system. Id. at 1365. The obviousness
rejection was predicated on combining the two sets of publications to meet a
limitation in the claim of using negative pressure to treat a wound. However,
wound treatment was not described in the negative pressure publications. Id. at
1361, 1363. Because each publication was complete in teaching a wound drainage
method, and there was no teaching that negative pressure could be used to treat
wounds, the court found “a person having ordinary skill in the art, who was merely
seeking to create a better device to drain fluids from a wound, would have no
reason to combine the features of both devices into a single device.” Id. at 1369.
The facts of this case are distinguishable. As explained above, Tuch’s
recitation of specific polymers is not complete, as was the device in Kinetic, giving
the skilled worker reason to have combined Tuch’s teachings with other teachings
about polymers in the medical device field.

D. Did the Examiner fail to identify a reason why a person of ordinary skill in the
art would have consulted Tu?
Patent Owner contends that the Examiner has not provided a reason for
having consulted Tu. Appeal Br. 18. Patent Owner argues that the Examiner has
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not given “any reason” for the skilled worker to have looked outside the drug
eluting stent (DES) field to identify polymers that could be used on a stent, when
the DES prior art already listed suitable polymers. Id. at 19. “The fact that Tu
teaches the use of elastomers in implantable devices is not a sufficient motivation,
since the DES references already identify thousands of suitable polymers.” Id.
Patent Owner is not correct that the Examiner has not provided “any” reason
to have consulted Tu. The Examiner specifically found that the skilled worker
would have been motivated to replaced VDF homopolymers as described by Tuch
with VDF-HFP copolymer because “Tu uses this copolymer to coat medical
implant devices” and that the copolymer would provide “a hydrophilic tissue
compatible porous layer, which promotes the elasticity and strength of a stent
while administering a controlled release drug with a reasonable expectation of
success.” RAN 11, 27.
The Examiner’s reasoning is supported by a preponderance of the evidence.
The following findings of fact are pertinent.
FF6. First, Tu expressly stated that its multi-layered materials “have a very
broad application in biomedical devices.” Tu, col. 2, ll. 36–37. Because a stent is
a biomedical device, the skilled worker in the DES field would have found Tu’s
teaching pertinent, even if DES devices are not specifically mentioned.
FF7. Second, Tu’s polyvinylidene fluoride co-hexafluoropropylene has the
properties described in Tuch as useful for its stent coating. These properties are
discussed below:
1. Biocompatibility. RAN 64 (¶ 115); 68 (¶ 125).
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FF8. Tuch’s polymers are biocompatible (“The polymer chosen must be a
polymer that is biocompatible . . . .” Tuch, col. 5, ll. 14–16) as they are in Tu (Tu,
col. 2, ll. 11–19).
2. Elasticity. RAN 64 (¶¶ 112,115); 68 (¶ 125).
FF9. Tuch teaches that elastic polymers are beneficial for coatings in
expandable stents.
FF10. When the polymeric overlayer on the stent is uniform and “made
with materials which have little elasticity,” Tuch teaches that “the overlayer can
sustain significant cracking during such deformation” and the “cracks can then act
as channels for more rapid elution of drugs from the drug-rich base coating.”
Tuch, col. 7, ll. 11–15.
FF11. Tuch teaches that “cracking of the overlayer can be reduced and drug
elution times increased by providing a porous overlayer on the stent.” Id. at col. 7,
ll. 16–18.
FF12. Tuch teaches that the polymer coating on the stent should be
“resilient” for stent expansion: “The inclusion of a polymer in intimate contact
with a drug on the stent allows the drug to be retained on the stent in a resilient
matrix during expansion of the stent . . .” Id. at 2:42–46. In context, Tuch uses the
term “resilient” to have its ordinary meaning, which is to be “able to return to an
original shape after being pulled, stretched, pressed, bent, etc.,” a synonym being
“elastic.”7

7 “Resilient” means “able to return to an original shape after being pulled,
stretched, pressed, bent, etc.” and a synonym is “elastic.” Resilient, Merriam-
Webster, http://www.merriam-webster.com/dictionary/resilient (accessed Jan. 28,
2015).
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FF13. Tu’s elastomers are also elastic. (“The outer layer of
poly(tetrafluoroethylene)/elastomer provides elasticity to improve compliance and
as a transitional matrix to provide desired bonding between the inner and very
outer layers.” Col. 7, ll. 56–60; “The optional third layer of elastomer provides a
hydrophilic tissue-compatible porous layer which promotes the elasticity, strength
and suturability for the whole composite.” Col. 3, ll. 61–64.)
3. Polyvinylidene fluoride (PVF)
FF14. Tuch teaches that polyvinylidene fluoride is a useful polymer for its
coating comprising a therapeutic substance. Tuch, col. 5, ll. 38–42; col. 2, ll. 36–
38.
FF15. The first elastomer on Tu’s list is a copolymer comprising
polyvinylidene fluoride and hexafluoropropylene. Tu, col. 2, ll. 23–24.
4. Therapeutic agent. RAN 74, ¶ 136.
FF16. Tuch teaches a polymer coating that delivers a therapeutic substance.
Tuch, col. 2, ll. 36–38.
FF17. Tu also teaches that its elastomer can contain therapeutic agents. Tu,
col. 8, ll. 45–47.

Analysis
Dr. Mikos in his first Declaration acknowledges that Tu discloses VDF-HFP
copolymer, but states “it does not describe such polymers as ‘preferred,’ or
otherwise single out VDF/HFP copolymers from among other disclosed
elastomers.” First Mikos Decl. ¶ 131. However, we know of no reason why VDF-
HFP must be singled out and characterized as “preferred,” when it is among a list
of polymers identified as useful for an implant.
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Furthermore, Dr. Mikos testified that the “physical and mechanical
properties that are important for the Tu vascular grafts are very different from the
physical and mechanical properties that are important for polymer coatings used on
drug-eluting stents [as in Tuch].” Id. ¶ 48. Dr. Mikos identifies elasticity as
important in vascular grafts. Id. ¶ 49. Dr. Mikos, however, did not explain how
elasticity is distinguishable from the ability of a polymer to be elongated or
deformed before breaking which he identified as an “important property” of a stent
polymer coating. Id. ¶ 50. That is, while Tu’s graft may have a different purpose
than Tuch’s stent, Dr. Mikos admits that a stent coating must be resilient (resist
deformation before breaking) which is the same property that Dr. Mikos identifies
as important in vascular grafts. FF12, FF13. Consequently, Dr. Mikos’s testimony
about the lack of reason to combine Tuch and Tu is not supported by persuasive
factual evidence.
Dr. Mikos testified that “Tuch does not identify the elasticity of a polymer as
a factor that should be considered when deciding whether or not to use it in a drug-
containing coating” (Second Mikos Decl. ¶ 11). However, this statement is
contrary to the teachings in Tuch as summarized in findings of fact 10–12. Since
Dr. Mikos did not address these disclosures, we give little weight to his testimony.
Velander v. Garner, 348 F.3d 1359, 1371 (Fed. Cir. 2003) (“In giving more weight
to prior publications than to subsequent conclusory statements by experts, the
Board acted well within [its] discretion.”); Yorkey v. Diab, 601 F.3d 1279, 1284
(Fed. Cir. 2010) (A factfinder has discretion to give more weight to one item of
evidence over another “unless no reasonable trier of fact could have done so”).
Patent Owner contends that elasticity would not have been a factor in
choosing a polymer coating for Tuch’s stent. Appeal Br. 15–16. This argument is
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not supported by the evidence. Tuch teaches that, when the stent delivery balloon
expands, the stent elements and coating deform (col. 7, ll. 9–11). When materials
are used for the polymers which “have little elasticity,” the polymer overlayer can
crack during the expansion and result in rapid drug elution. FF10. Tuch teaches
one way to reduce the cracking is to provide a porous overlayer on the stent. FF11.
Because Tuch teaches a problem with cracking when materials having “little
elasticity” are utilized in the polymer layer, one of ordinary skill in the art would
have reasonably sought materials with high elasticity to avoid the problem when
the stent is expanded.
Furthermore, Tuch teaches that using a resilient matrix during expansion of
the stent is beneficial for drug retention. FF12. Resilient is a synonym for elastic.
Fn. 5. Tu, as indicated above, teaches elastomers that possess elasticity and
strength, providing the reason to have used them in Tuch’s medical device.
In addition to this, we cannot ignore a publication by Le Morel that was
cited in the related merged reexamination. Le Morel was also mentioned in a
Second Declaration by Michael N. Helmus, Ph.D. executed on December 3, 2012,
provided by Requester. Second Helmus Decl. ¶ 43. (The Second Helmus
Declaration was entered and considered by the Examiner as noted in the RAN 4, ¶
5.) The following findings of fact from LeMorel are pertinent:
FF18. Le Morel teaches “a bioactive prosthesis including a medium coated
with a polymer layer having reactive functions, and a bioactive substance fixed to
the prosthesis through said reactive functions.” Le Morel 2.
FF19. The prosthesis can be a stent placed in an artery. Id. at 1. Le Morel
teaches that restenosis is a complication of stent placement. Id. at 1–2. To address
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this problem, Le Morel teaches treating restenosis using a bioactive substance
fixed to the prosthesis through a polymer. Id. at 2–3.
FF20. Le Morel teaches that the stent can be coated with a biocompatible
material on the surface which can be a polymer. Id. at 3.
FF21. The polymer layer is described by Le Morel as follows (brackets and
emphases added):
The polymers that may be used in the invention to form the
surface of the medium may be of various types. By way of examples,
we cite [1] polyolefins such as polyethylene, polypropylene,
polybutylene, poly (4-methyl-1-pentene) and copolymers of ethylene
and of vinyl acetate; [2] fluorinated polymers such as
polytetrafluoroethylene, copolymers of ethylene and of
tetrafluoroethylene, vinylidene polyfluoride a[n]d copolymers of
vinylidene fluoride and of hexafluoropropylene or of
trifluoroethylene; [3] polyesters like polyterephthalate ethylene;
polyethers like poly([o]xymethylene) and poly(oxyphenylene); [4]
elastomers like natural rubbers and silicons, and polyurethanes.
Id. at 3.
There are four main classes of useful polymers named in Le Morel, and the
VDF-HFP copolymer is expressly described as an example of one of the polymer
classes. FF21. This disclosure by Le Morel clearly establishes that one of
ordinary skill in the art knew that VDF-HFP copolymer could be used on a stent
surface. Apparently, the Examiner did not adopt rejections in the related merged
reexamination based on Le Morel because the bioactive substance is attached to
the polymer through reactive groups rather than being mixed with it.8 FF18 and
FF20. However, such disclosure does not negate Le Morel’s teaching that VDF-
HFP is suitable for a stent polymer and certainly is relevant, particularly because

8 Office Action in merged reexamination mailed Jan. 21. 2011, page 78.
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Patent Owner has specifically argued that VDF-HFP would not be suitable as a
stent polymer.

E. Would it have been obvious to have utilized the copolymer of VDF and HFP on
the luminal surface of a stent?
With respect to the lack of a reason to have chosen VDF-HFP copolymer
from Tu, Patent Owner argues:
Tu teaches that the outer elastomeric layer of its disclosed vascular
graft (which is the layer that may possibly be formed of VDF/HFP)
“provides a hydrophilic tissue-compatible porous layer which
promotes the elasticity, strength and suturability for the whole
composite” (col. 3: 61-64) while the graft’s inner luminal layer, which
is prepared of poly(tetrafluoroethylene), is the one that “provides the
basic hydrophobic, blood compatible fibril-nodal microstructure”
(col. 3: 44-47, emphasis added). Indeed, Tu does not merely teach
that the blood-contacting portions of the graft should be made of
poly(tetrafluoroethylene) rather than an elastomer like VDF/HFP, the
reference actually teaches away from allowing any elastomeric
polymer to contact the flowing blood, stating “[i]t is not desired to
have the elastomer permeate the poly(tetrafluoroethylene)/elastomer
layer and migrate into the lumen” (col. 8: 40-43).
Appeal Br. 20–21.
This argument is not supported by a preponderance of the evidence.
FF22. Tu describes a “multilayered poly(tetrafluoroethylene)/elastomer
material for use as an implant where there is improved luminal hydrophobicity,
compliance, strength and elasticity.” Tu, col. 2, ll. 8–11.
FF23. As stated by Patent Owner, Tu teaches in several passages of the
patent that the luminal, blood contacting surface, is made of
poly(tetrafluoroethylene). Id. at col. 2, ll. 47–48.
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FF24. Tu also teaches a second layer which is porous and comprises a
mixture of poly(tetrafluoroethylene) and elastomer. Id. at col. 2, ll. 50–52.
FF25. The second layer is described by Tu as being the “less hydrophobic
second layer [which] provides excellent adhesive sites for bonding a hydrophilic
outer layer to make a final composite with asymmetric hydrophobicity.” Id. at col.
2, ll. 65–68. The second layer is described by Tu as a transitional phase between
an inner layer and outer layer. Id. at col. 3, ll. 48-51.
FF26. However, Tu also has broader disclosure. RAN 74, ¶ 135.
Specifically, in the section titled “Summary of the Invention,” an embodiment is
described as follows:
Another embodiment comprises a luminal layer of
poly(tetrafluoroethylene)/elastomer mixture and a second layer of
poly(tetrafluoroethylene).
Id. at col. 3, ll. 9–11.
FF27. Claim 28 of Tu, which depends from claim 1, is directed to this
embodiment:
1. A biologically compatible multi-layered in vivo implantation
material comprising
a porous, luminal layer of poly(tetrafluoroethylene)
and
a second layer comprising a porous mixture of
poly(tetrafluoroethylene) and elastomer.
28. The material in accordance with claim 1 in which the luminal
layer comprises a porous mixture of poly(tetrafluoroethylene) and
elastomer, and the second outer porous layer is
poly(tetrafluoroethylene).
(Emphasis added.)
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Patent Owner’s s argument that Tu “actually teaches away from allowing
any elastomeric polymer to contact the flowing blood” (Appeal Br. 21) is not
supported by a preponderance of the evidence because Tu expressly teaches an
embodiment in its Summary of the Invention in which the blood contacting
luminal layer9 of an implantable device can comprise poly(tetrafluoroethylene) and
elastomer. FF26–FF27. Patent Owner’s argument to the contrary focuses on
different embodiments without acknowledging this explicit teaching.
Furthermore, as discussed above, Le Morel teaches the VDF-HFP
copolymer coating on a stent which would include outer and luminal surfaces.
Dr. Mikos testified that “[i]n view of Tu’s admonition to avoid contact
between the elastomers and the lumen of vascular grafts, those of ordinary skill in
the art would have reasonably expected that if a device such as a heart valve leaflet
were prepared according to Tu, it would not include the optional elastomeric
coating.” Second Mikos Decl. ¶ 30. We give Dr. Mikos’s opinion little weight
because he failed to address the explicit teaching in Tu of a polymer comprising an
elastomer on the luminal surface. FF26–28.

F. Would there have been a reasonable expectation that the Examiner’s proposed
combination with Tu would have been successful?
Patent Owner contends that the Examiner “ignores the fact that a stent [of
Tuch] is placed within the vessel lumen, while the elastomeric layer in the Tu
grafts is on the exterior surface, where it primarily contacts the tissues outside the

9 The luminal layer is taught by Tu to contact the blood (“In this application, the
extrudate would have a relatively thin luminal layer of poly(tetrafluoroethylene)
alone, having distinct fibril nodal microstructure for excellent blood contact.” Tu,
col. 7, ll. 50–55.

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vessel.” Appeal Br. 20. Thus, Patent Owner argues that it would have not been
reasonably expected that Tu’s polymer would meet the requirements for a DES
stent and be successfully employed as one. Id.
This argument has already been addressed above. The Examiner did not
ignore this argument, but rather pointed to the disclosure identified above of Tu’s
teaching of VDF-HFP elastomer as part of the luminal layer of the device (RAN
74, ¶ 135), providing factual evidence that such polymer would be effective when
contacting blood. Moreover, we again refer to Le Morel, which teaches that VDF-
HFP copolymers can be used to make stents. This issue is also addressed in more
detail in Section G below, which cited Lilenfeld as another reference describing
VDF-HFP on an implantable device.

G. Choice of the VDF-HFP copolymer
The choice of the specific VDF-HFP copolymer in the claimed ratio of 85%
VDF and 15% HFP is in dispute in this appeal. The initial Request for
Reexamination relied upon Lo, Wille, and Modern Fluoropolymers for the specific
ratios. Request 5–6. However, these publications are not directed to medical or
biological uses of the polymer, and Patent Owner has argued that one of ordinary
skill in the art would not have consulted them. Appeal Br. 21.
First, there is strong evidence that the choice of a VDF-HFP polymer for a
stent would have been obvious to one of ordinary skill in the art. As mentioned
above and also in the Request, stents coated with VDF-HFP are described in Le
Morel. See above and Request 5. In addition, Tu describes the copolymer for
vascular grafts. Request 4–5. Thus, the VDF-HFP copolymer had been used for
medical applications prior to the claimed invention.
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As for the 85:15 copolymer ratio, the Request relied on industrial
applications, such as Lo. However, there is an even more pertinent publication,
Lilenfeld, which describes a biomedical application of a copolymer of VDF-HFP,
namely, for surgical filaments. The Lilenfeld publication was specifically cited in
the related reexamination (Reexamination Control 95/000,542 and 95/000,552) and
by relying on it here, we address any perceived deficiency in the Examiner’s
reliance on Lo’s disclosure. The following disclosure from Lilenfeld is of
particular relevance to the obviousness of choosing the claimed copolymer ratio of
85% VDF and 15% HFP.
FF28. “ABSTRACT Surgical filaments are made from a copolymer of
vinylidene fluoride and hexafluoropropylene.”
FF29.
The vinylidene fluoride copolymers used in the invention are those
that contain hexafluoropropylene as a comonomer. The proportions of
comonomer have not been found to be narrowly critical. The
comonomer is used in an amount sufficient to enhance the compliance
and other handleability properties of the surgical filaments made from
the copolymer, while still retaining an acceptable level of strength
properties. Within these constraints, as a general rule, there will
usually be from about 1 weight percent to about 15 weight percent of
polymerized comonomer in the copolymer, the remainder being
polymerized vinylidene fluoride.
Lilenfeld, col. 2, ll. 19–30 (emphasis added)
FF30.
Copolymer A—A random copolymer of 90 weight percent vinylidene
fluoride and 10 weight percent hexafluoropropylene . . .
Copolymer B—A random copolymer of 95 weight percent vinylidene
fluoride and 5 weight percent hexafluoropropylene . . .
Copolymer C—A random copolymer of 87 weight percent vinylidene
fluoride and 13 weight percent hexafluoropropylene . . .
Id. at col. 2, 67 to col. 3, 11 (emphasis added).
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Because neither Le Morel nor Tu disclose the amounts of the comonomers
in the VDF-HFP copolymer to be used, one of ordinary skill in the art would have
reasonably consulted other biomedical applications for useful amounts, at least as a
starting point. Thus, in our opinion, the disclosure in Lilenfeld of a specific ratio
of 87:13 and an amount of HFP up to 15%, with the amounts of HFP not being
“narrowly critical” (FF29, FF30), reasonably suggests the claimed copolymer ratio
of 85:15 on stent. The fact that three publications in the biomedical field described
VDF-HFP as useful for implantable devices—sutures in Lilenfeld, vascular grafts
in Tu, and stents in Le Morel—in our opinion made VDF-HFP an obvious choice
for a stent. The specific amounts in the claim would have been reasonably
expected to be compatible with body tissue and blood because Lilenfeld teaches
such amounts for a suture which is placed in the body in contact with the VDF-
HFP.
Lo is cited by the Examiner for teaching the copolymer in the recited
amounts and having properties that would make it useful on a stent. RAN 44. We
specifically rely on Lo for its further teaching that 85% VDF and 15% HFP
copolymer has characteristics that would make it useful on a stent. Taken together
with the other references, Lilenfeld and Lo have reasonably suggested the selection
of a VDF-HFP copolymer having the claimed amounts of VDF and HFP.
FF31. Lo teaches that an 85:15 copolymer is advantageous with respect to
flexibility, elasticity, extensibility, tensile strength, and reverse elongation. Lo,
col. 2, ll. 33–36, 47, and 56–58; RAN 44.
FF32. Specifically, Figure 1 of Lo shows an increase of tensile PSIG and
reversible elongation from about 86 mol percent to a maximum of about 94 mol
percent with a copolymer made of vinylidene fluoride and hexafluropropene.
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FF33. Lo also teaches that “[a]bove about 94 mol percent vinylidene
fluoride (i.e. less than 6 mol percent hexafluoropropene) the copolymer is
essentially crystalline in nature and the reversible elongation decreases rapidly.”
Lo, col. 9, ll. 33–36.
The Examiner found that one of ordinary skill in the art would have been
motivated to have used Lo’s polymer having these advantageous properties in
Tuch because Tuch teaches a problem with coatings with low elasticity. Because
VDF:HFP is expressly described by Tu as useful for an implantable medical
device, the skilled worker would have considered known, bio-compatible (as
disclosed in Lilenfeld), commercially available VDF:HFP copolymers, including
the copolymer disclosed in Lo, as candidates for use in the stent suggested by the
combined teachings of Tuch, Tu, and Le Morel. Patent Owner’s argument that
Lo’s uses are industrial and therefore not pertinent to stents (Appeal Br. 21) is
unpersuasive since Lo was cited for teaching the properties of VDF:HFP
copolymer which had been taught to be useful by Tu in a medical device and in the
stent by Le Morel.
In characterizing Lo’s teachings, Dr. Mikos acknowledges that Lo teaches
its copolymers are “flexible” and having “good reversible elongation” (First Mikos
Decl. ¶¶ 72, 73), properties useful for stents. Dr. Mikos argues that the skilled
worker would not have consulted Lo because it is directed to industrial
applications (id. ¶ 132). However, this defines the field pertinent to the invention
too narrowly because it is clear that not all polymers utilized in the biomedical
field were developed for that sole purpose. Specifically, Tu refers to DuPont
Company polymers (at col. 1, l. 55) and Paton also refers to what appears to be
industrially available polymers for biomedical devices (at Abstract, cols. 1–4). See
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also Requester’s Resp’t Br. 4 (referring to admissions made by made by Patent
Owner).

H. Does the cited prior art fail to teach or suggest the use of VDF-HFP
copolymers as carriers for drug delivery?
Patent Owner contends that the cited prior art does not teach or suggest the
use of the copolymer of VDF-HFP for drug delivery. Patent Owner argues that
“Tu makes a passing reference to placing a therapeutic agent in an optional outer
elastomer layer, but does not connect this teaching to any of the different polymers
that may be used in the outer elastomer layer.” Appeal Br. 22. Patent Owner
asserts that a polymer intended to be used as a drug delivery system must possess
certain characteristics, including to “serve as a carrier that will elute the drug for a
time and at a rate that is sufficient to reduce the incidence of restenosis.” Id. at 23.
Patent Owner asserts that the “prior art provided no teaching or suggestion that any
VDF/HFP copolymer (much less one of the type claimed) would fulfill these
requirements.” Id.
The Examiner thoroughly responded to this argument.
148. Tu emphasizes that the elastomer layer may contain a
“therapeutic agent” mixed with the elastomer solution (column 8,
lines 45-47 and column 9, lines 65-68 of Tu). Tu also teaches that
“[i]n all embodiments” its elastomer can contain a drug such as
heparin that may be released into the surrounding environment[]
(emphasis added) (column 9, lines 65-68). As [such,] Tu specifically
teaches that the copolymer of VDF-HFP comprises the elastomeric
layer of an implanted medical device (column 4, lines 30-32).
RAN 80.
We have reviewed the disclosure in Tu cited by the Examiner, and find that
it is more than just simply a “passing reference” to incorporating a drug into the
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elastomer solution, but an express teaching to do so that specifically extends to “all
embodiments” described in Tu. Id. Consequently, we find Patent Owner’s
arguments unavailing.

SECONDARY CONSIDERATIONS
Factual considerations that underlie the obviousness inquiry include the
scope and content of the prior art, the differences between the prior art and the
claimed invention, the level of ordinary skill in the art, and any relevant secondary
considerations. Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966). Relevant
secondary considerations include commercial success, long-felt but unsolved
needs, failure of others, praise, and unexpected results. KSR Int'l Co. v. Teleflex
Inc., 550 U.S. 398, 406 (2007); Institut Pasteur & Universite Pierre et Marie Curie
v. Focarino, 738 F.3d 1337, 1344 (Fed. Cir. 2013); In re Soni, 54 F.3d 746 (Fed.
Cir. 1995). Secondary considerations are “not just a cumulative or confirmatory
part of the obviousness calculus but constitute [] independent evidence of
nonobviousness . . . [and] enable [] the court to avert the trap of hindsight.” Leo
Pharm. Prods., Ltd. v. Rea, 726 F.3d 1346, 1358 (Fed. Cir. 2013) (internal
quotation marks and citations omitted). “This objective evidence must be
‘considered as part of all the evidence, not just when the decisionmaker remains in
doubt after reviewing the art.’” Transocean Offshore Deepwater Drilling, Inc. v.
Maersk Drilling USA, Inc., 699 F.3d 1340, 1349 (Fed. Cir. 2012) (internal citations
omitted).
Patent Owner contends that the Examiner failed to credit the evidence of
nonobviousness of the claimed invention. Appeal Br. 25. As evidence, Patent
Owner cited studies performed with the Xience V stent. Patent Owner asserts that
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Xience V is a stent sold by Abbott Laboratories that “employs Solef® 21508
(Patent Owner’s Response to ACP, at pgs. 4–5), a VDF:HFP copolymer that
comprises about 85% VDF and about 15% HFP.” Id. at 26.

Copying
Patent Owner states that the invention of the ’773 Patent has been copied
and adopted by others in the industry, including by Abbott (Xience V stent) and by
Boston Scientific (Promus stent). Appeal Br. 26. As evidence, Patent Owner cites
to paragraph 261 of the First Mikos Declaration. However, paragraph 261 merely
alleges copying by Abbott and Boston Scientific without factual evidence or
analysis to support this statement. RAN 82–83. Consequently, without adequate
evidence that Abbott and Boston Scientific copied the claimed invention, we agree
with the Examiner’s determination to give this argument little weight.

Commercial success
Patent Owner contends that commercial success of the claimed invention is
demonstrated by the statement in Abbott’s 2008 Form 10K that “‘Xience V
became the market-leading drug eluting stent in the U.S. in the fourth quarter of
2008,’ within just three months of FDA approval” and Dr. Mikos’s statement that
the “PVDF-HFP coating used in the Xience V stent is an important factor in the
clinical success of the Xience V stent, and therefore also in the commercial success
of the Xience V and Promus stents.” First Mikos Decl. ¶ 262. Patent Owner
further cited Abbott’s fact sheet on the Xience V stent which represented that “the
composition of the polymer coating” in the Xience V stent “is important in overall
clinical safety and efficacy outcomes.” Appeal Br. 27 (n. 11). Patent Owner also
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cited evidence that Xience’s thin, nonreactive polymer accounted for its success.
Id. at 17 (fn. 5).
For evidence of secondary considerations to be accorded substantial weight,
there must be a nexus between the claimed invention and what is relied upon as the
secondary consideration. In re GPAC, Inc., 57 F.3d 1573, 1580 (Fed. Cir. 1995).
A nexus is established when the secondary consideration is attributed to a feature
of the claimed invention. Ormco Corp. v. Align Tech., Inc., 463 F.3d 1299, 1311–
12 (Fed. Cir. 2006).
In this case, even if there is evidence that the coating is one factor that
contributed to the success of Xience V, there is additional evidence that the drug
and stent material are also important reasons for its success. Yet, neither the drug
or the stent material is recited in claims 4 and 6–9
In this regard, as noted by the Examiner (RAN 92, ¶ 171), Ex. 9 describes
the drug and stent frame as reasons for the success of Xience V:
Assessing why second-generation DES such as Xience may be
superior to earlier-generation stents, the editorialists point out
that they may differ on many fronts: the antiproliferative agent (in this
case everolimus vs. paclitaxel), the polymer layer (Xience’s is
biocompatible), and stent frame (flexible cobalt-chromium vs.
stainless steel). For example, improved stent design may result in
better stent apposition and endothelialization as well as reduced
platelet aggregation and thrombus formation. However, since the
relative contribution of each of these elements to the enhanced
performance of Xience is unknown, the study results are not
necessarily applicable to other everolimus-eluting stents, Drs. Lange
and Hillis caution.
Ex. 9 (emphases added).
Similarly, Exhibit 8 also contains statements that attribute the success of the
Xience to the drug and stent design, neither which are recited in the claim.
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Everolimus is a more potent drug than those used in the first-
generation coated stents and also is contained in a thin, inert polymer
that is less likely to cause inflammation, [Dr. Gregg. W. Stone, an
interventional cardiologist who is a professor of medicine at Columbia
University and who took part in the controlled trials that led to FDA
approval of Xience] said. The Xience stent itself is also thinner than
the previous devices, he added.
Ex. 8, 1.
Patent Owner represented that Dr. Stone had attributed Xience’s commercial
success to the polymer coating. Appeal Br. 27–28. However, in Exhibit 5, it was
reported that Dr. Stone highlighted several reasons for the success of Xience, and
not only the polymer coating as indicated by Patent Owner:
Stone, who first presented the SPIRIT III results at the TCT 2007
meeting, told heartwire that two-year results will be presented at the
upcoming EuroPCR meeting in Barcelona. He highlighted design
characteristics of the Xience – thinner struts; a thin, nonreactive
polymer; and a drug with similar potency to sirolimus – as key
reasons not only for the reduced late loss at nine months, fewer repeat
procedures at one year, and fewer periprocedural MIs, but also as
factors that may ensure the stent also performs better over time.
Ex. 5 (underlining added).
Thus, it has not been established that the claimed polymer in the 85:15 wt%
ratio is responsible for the asserted success of the claimed invention. Rather, the
drug and the stent design were also identified as “key reasons” for the success of
Xience, yet neither of these is recited in the claims. Moreover, commentators on
the Xience trials specifically noted the study results could not be extrapolated to
other everolimus-eluting stents because “the relative contribution of each of these
elements [the antiproliferative agent, the polymer layer, and stent frame] to the
enhanced performance of Xience is unknown.” Ex. 9, 2. Consequently, the
preponderance of the evidence does not support a nexus between commercial
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success and the merits of the claimed invention (“For objective evidence to be
accorded substantial weight, its proponent must establish a nexus between the
evidence and the merits of the claimed invention.” GPAC, 57 F.3d at 1580).

Unexpected results
A showing of “unexpected results” can be used to demonstrate the non-
obviousness of the claimed invention. In re Soni, 54 F.3d at 750 (“One way for a
patent applicant to rebut a prima facie case of obviousness is to make a showing of
‘unexpected results,’ i.e., to show that the claimed invention exhibits some superior
property or advantage that a person of ordinary skill in the relevant art would have
found surprising or unexpected.”). Those results must be “surprising or
unexpected” to one of ordinary skill in the art when considered in the context of
the closest prior art. Soni, 54 F.3d at 750; Iron Grip Barbell Co., Inc. v. USA
Sports, Inc., 392 F.3d 1317, 1322 (Fed. Cir. 2004) (A showing of “new and
unexpected results” must be “relative to the prior art.”); In re Baxter Travenol
Labs., 952 F.2d 388, 392 (Fed. Cir. 1991) (“[W]hen unexpected results are used as
evidence of nonobviousness, the results must be shown to be unexpected compared
with the closest prior art”). To establish unexpected results, the claimed subject
matter must be compared with the closest prior art. Id.
Citing paragraph 264 of Dr. Mikos’s first Declaration, Patent Owner
contends that “the PVDF-HFP coated Xience V stent is more thromboresistant
(i.e., shows greater tendency to reduce thrombus formation) than other drug-eluting
stent coatings.” Appeal Br. 27. Patent Owner also contends that “numerous
clinicians have also emphasized that the PVDF-HFP polymer used in the Xience V
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stent shows unexpectedly less inflammation,” again citing to the First Mikos
declaration. Id. at 27–28.
Paragraph 264 of the first Mikos Declaration refers to Abbott’s data in
Exhibits 6 and 7. Exhibit 6 is undated. Exhibit 6 at ABT046618 shows that the
weight of thrombus adhered to the stent for Xience V was less than for the Cypher,
Endeavor, and Taxus Liberté stents. ABT046619 shows that Xience V had lower
thrombus adherence “due to smooth coating integrity and hemocompatability of
the XIENCE V Fluoropolymer” as compared to the Vision stent.
Dr. Mikos did not fully describe the coatings, stent materials, or therapeutic
agents utilized in the stents to which the performance of Xience V was compared.
Cypher comprises the drug sirolimus combined with a polymer blend of two non-
erodible polymers, polyethylene-co-vinyl acetate (PEVA) and poly n-butyl
methacrylate (PBMA), to form the basecoat. First Mikos Decl. ¶ 23. To establish
unexpected results, the comparison must be against the closest prior art. Baxter,
952 F.2d at 392; Iron Grip Barbell Co., 392 F.3d at 1322. Dr. Mikos did not
establish that the coating on Cypher constitutes the closest prior art. Patent Owner
did not present arguments that the stents to which Xience was compared
constituted the closest prior art.
In addition to this, Dr. Mikos did not provide evidence that the purported
improved results for Xience V was due to a claimed feature, rather than an
unclaimed feature, such as the drug or stent material. Ormco Corp., 463 F.3d at
1311–12. Dr. Mikos also did not state the results would have been unexpected or
surprising to one of ordinary skill in the art. Soni, 54 F.3d at 750.
Exhibit 7 was also cited by Dr. Mikos as evidence of unexpected results.
First Mikos Decl. ¶ 264. Exhibit 7 is undated. Dr. Mikos cited page 28 of Exhibit
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8. This page shoes that the average thrombus weight for Xience was less than for
“Vision BMS.” “BMS” is a bare metal stent. The comparison therefore does not
appear to be with the closest prior art since Tuch describes polymer coated stents
and Vision BMS is bare metal. Baxter, 952 F.2d at 392.
Dr. Mikos further testified in his written Declaration that “numerous
clinicians have also emphasized that the PVDF-HFP polymer used in the Xience V
stent shows unexpectedly less inflammation.” First Mikos Decl. ¶ 265. As
evidence, Dr. Mikos cited Exhibits 8 and 9.
Exhibit 8 is a news article. The article mentions that Xience V is “less likely
to cause inflammation.” Exhibit 9 is also a news article. The article states:
In a telephone interview with TCTMD, Robert S. Schwartz, MD, of
the Minneapolis Heart Institute Foundation (Minneapolis, MN),
underlined the role of the polymer in differentiating between the stent
generations, saying that Taxus’ older polymer was more likely to
induce inflammation.
Ex. 9, 2.
Notwithstanding that the comparison is not necessarily with the closet prior
art, the cited articles do not provide any data to substantiate the assertion that the
polymer shows “unexpectedly less inflammation.” Exhibit 8 states that the
polymer “is less likely to cause inflammation,” but does not describe how this
determination was made and in comparison to what specific polymer. No
experimental details are provided. For this reason, we will not accord Dr. Mikos’s
opinion in paragraph 264 about unexpected results associated with the claimed
polymer any weight. In re Am. Acad. of Sci. Tech Ctr., 367 F.3d 1359, 1368 (Fed.
Cir. 2004) (“[T]he Board [or the Examiner] is entitled to weigh the declarations
and conclude that the lack of factual corroboration warrants discounting the
opinions expressed in the declarations.”).
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Industry praise
Patent Owner states that there “has been industry praise for Xience V that is
attributable to the claimed invention.” Appeal Br. 27.
We have reviewed Exhibit 5 cited by Patent Owner. However, as discussed
above, it is not evident from this article and the others of record that the success
and praise is a result of the claimed invention, rather than an unclaimed feature
such as the drug or stent design. Exhibit 9, for example, compares Xience
containing the everolimus drug in its coating with a paclitaxel stent. The article
asks “‘Should we abandon paclitaxel-eluting stents in favor of second-generation
everolimus-eluting stents on the basis of the results of [this] study’,” indicating
that, at least in this case, the praise and success may be related to the everolimus
drug.

Copolymer
Patent Owner argues the recited copolymer has unexpected properties
because it causes less inflammation and is more thromboresistant compared to
commercially available stents. While we have found that the comparisons are not
necessarily with the closest art and deficient because Patent Owner did not identify
the polymer in all of the comparative stents nor the experimental details, we
recognize that the comparisons are still informative. The question is whether the
copolymer properties are sufficient, when considered with the evidence of record,
to establish the non-obviousness of the claimed subject matter.
Secondary considerations are generally not persuasive when the prior art
possesses the same characteristics relied upon by the patent owner in the evidence
of the secondary consideration. In re Baxter, 952 F.2d at 392; J.T. Eaton & Co.,
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Inc. v. Atlantic Paste & Glue Co., 106 F.3d 1563, 1571 (Fed. Cir. 1997). For a
secondary consideration to be persuasive evidence of nonobviousness, it must be
connected to the features of the claimed invention “beyond what was readily
available in the prior art.” See Eaton, 106 F.3d at 1571. In this case, we must
decide whether the recited polymer coating was “readily available” in the prior art.
Several teachings in the prior art, which we have already discussed, are pertinent to
this determination.
First, as discussed previously, Tu describes an embodiment in which the
copolymer of VDF-HFP is on the luminal blood contacting surface of a vascular
implant. FF26–FF28.
Second, Le Morel describes using “fluorinated polymers such as . . .
vinylidene fluoride and of hexafluoropropylene” on a stent. FF20–FF21.
Third, Lilenfeld describes the VDF-HFP copolymer in the recited amounts
as a biologically compatible material.
While there is no specific working example in which the copolymer was
applied to a stent, certainly the disclosures in Tu, Le Morel, and Lilenfeld are
strong evidence that a stent coated with VDF-HFP was “readily available” in the
prior art at the time of the invention. Any property of a stent coated with VDF-
HFP would have been possessed by Le Morel’s stent, including the polymer’s
reduced inflammatory response and thromboresistance, albeit an unrecognized at
the time. “Mere recognition of latent properties in the prior art does not render
nonobvious an otherwise known invention.” In re Baxter Travenol Labs., 952 F.2d
at 392.
However, the claims are not solely directed to VDF-HFP, but require a
specific ratio of them, namely, a “film coating comprising a polyfluoro copolymer
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comprising about 85 weight percent of polymerized residue of vinylidenefluoride
and about 15 weight percent of polymerized residue of hexafluoropropylene mixed
with effective amounts of a therapeutic and/or pharmaceutical agent.” Claim 4.
This specific ratio is not described in Tu or Le Morel. Nonetheless, this ratio is
suggested by Lilenfeld who discloses up to 15% HFP as claimed and uses it in the
body in contact with biological tissues. The property of being “less likely to cause
inflammation” (First Mikos Decl. ¶ 265) and more thromboresistant (id. ¶ 264)
might not have been recognized by Lilenfeld, but Lilenfeld considered it to be
biocompatible and thus such additional advantageous characteristics, if any, would
necessarily follow upon combination of the references. Such characteristics, which
have not been shown to be unexpected, are thus not a basis for patentability
because the polymer had been used in the body where it would have exhibited such
characteristics, albeit unrecognized. In re Dillon, 919 F.2d 688, 693 (Fed. Cir.
1990) (en banc) (“[T]he statement that a prima facie obviousness rejection is not
supported if no reference shows or suggests the newly-discovered properties and
results of a claimed structure is not the law.”).

SUMMARY
After considering the evidence in this record, including the evidence of
secondary considerations and the Declarations, we conclude that a preponderance
of the evidence supports the Examiner’s determination that claim 4 is unpatentable
under 35 U.S.C. § 103(a) (pre-AIA) as obvious in view of Tuch, Tu, Lo, , Le
Morel, and Lilenfeld. Dependent claims 6–9 were not argued separately. We
affirm the rejection of these claims for the reasons given by the Examiner and
those given above.
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This decision contains a new ground of rejection under 37 C.F.R. § 41.77(b).
Section 41.77(b) provides that “[a] new ground of rejection . . . shall not be
considered final for judicial review.” That section also provides that Patent
Owner, WITHIN ONE MONTH FROM THE DATE OF THE DECISION, must
exercise one of the following two options with respect to the new grounds of
rejection to avoid termination of the appeal proceeding as to the rejected claims:
(1) Reopen prosecution. The owner may file a response requesting
reopening of prosecution before the examiner. Such a response must
be either an amendment of the claims so rejected or new evidence
relating to the claims so rejected, or both.

(2) Request rehearing. The owner may request that the proceeding be
reheard under § 41.79 by the Board upon the same record. The request
for rehearing must address any new ground of rejection and state with
particularity the points believed to have been misapprehended or
overlooked in entering the new ground of rejection and also state all
other grounds upon which rehearing is sought.

In accordance with 37 C.F.R. § 41.79(a)(1), the “[p]arties to the appeal may
file a request for rehearing of the decision within one month of the date of: . . .
[t]he original decision of the Board under § 41.77(a).” A request for rehearing
must be in compliance with 37 C.F.R. § 41.79(b). Comments in opposition to the
request and additional requests for rehearing must be in accordance with 37 C.F.R.
§ 41.79(c)-(d), respectively. Under 37 C.F.R. § 41.79(e), the times for requesting
rehearing under paragraph (a) of this section, for requesting further rehearing under
paragraph (c) of this section, and for submitting comments under paragraph (b) of
this section may not be extended.
An appeal to the United States Court of Appeals for the Federal Circuit
under 35 U.S.C. §§ 141–144 and 315 and 37 C.F.R. § 1.983 for an inter partes
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reexamination proceeding “commenced” on or after November 2, 2002 may not be
taken “until all parties’ rights to request rehearing have been exhausted, at which
time the decision of the Board is final and appealable by any party to the appeal to
the Board.” 37 C.F.R. § 41.81. See also MPEP § 2682 (8th ed., Rev. 8, July 2010).
No time period for taking any subsequent action in connection with this
appeal may be extended under 37 C.F.R. § 1.136(a).
Requests for extensions of time in this inter partes reexamination
proceeding are governed by 37 C.F.R. § 1.956. See 37 C.F.R. § 41.79.
In the event neither party files a request for rehearing within the time
provided in 37 C.F.R. § 41.79, and this decision becomes final and appealable
under 37 C.F.R. § 41.81, a party seeking judicial review must timely serve notice
on the Director of the United States Patent and Trademark Office. See 37 C.F.R.
§§ 90.1 and 1.983.

AFFIRMED
37 C.F.R. § 41.77(b)

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PATENT OWNER:

BAKER & HOSTETLER LLP
Cira Centre, 12th Floor
2929 Arch Street
Philadelphia, PA 19104-2891