Ex Parte Santilli et al

Patent Trial and Appeal Board

Jul 14, 2016

11746337 (P.T.A.B. Jul. 14, 2016)

IN THE UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Appellants: Albert N. Santilli and William H. Seitz, Jr.
Title: ORTHOPEDIC IMPLANTS COATED WITH PYROLYTIC CARBON
Appeal No: 2013-001155
Serial Number: 11 /746,337
Filed: May 9, 2007
Examiner: Leslie Ann Coburn
Art Unit: 3774
Cont. No. 2490
Docket Number: KSl-15813.002
Honorable Commissioner for Patents
P. 0. Box 1450
Alexandria, VA 22113-1450
REQUEST FOR REHEARING
Sir:
This request for rehearing is filed in accordance with 37 C.F.R. § 41.52 and in
response to the Board's decision in the above-noted application that was mailed
February 11, 2016.
With respect to the affirmance of the obviousness rejection of claims 1, 2, 4, 6-8,
10 and 13 under 35 U.S.C. § 103(a), appellants believe that the Board has
misapprehended or overlooked appellants' arguments concerning the Rathenow
reference and other issues. Misapprehending or overlooking appellants' arguments
constitutes a basis for appellants to seek rehearing. 37 C.F.R. 41.52(a)(1 ).
1. Appellants Raised Arguments Specific to Particular Claims
The Board stated that "Appellants provide only general arguments and do not
raise arguments specific to any particular claims." Decision at 4, citing App. Br. at 9-17.
Appellants believe that they did raise arguments specific to particular claims, and
request rehearing.
Appellants discussed the limitations of each of the claims on appeal at pages 3-5
and 13-14 of their Brief. Arguments concerning those limitations were made at pages
14-17. For example, appellants noted that the article claims (claims 1, 2, 4, 6 and 7) and
the method claims (claims 8, 10 and 13) call for an orthopedic implant having a metal
substrate selected from the group consisting of titanium, stainless steel, cobalt chrome
steel, and alloys and mixtures thereof that defines an articulating surface. App. Br. at
13. Appellants argued that the Bokros reference did not disclose such a substrate
material. Id., at 15.
Also, appellants discussed the failure of Bokros to disclose the material claimed
in particular claims. At the sentence bridging pages 15 and 16, appellants stated:
"Bokros also fails to disclose the claimed use of alloys of pyrolytic carbon in addition to
pure pyrolytic carbon (see claims 4, 7 and 1 O)."
Similarly, appellants noted in their Reply Brief that 2-3 mm is an extremely thick
layer to be deposited by vapor deposition, and that the examiner had not cited a
reference that teaches or suggests vapor deposition of pyrolytic carbon to such an
extent: "In particular, claims 8, 10 and 13 are method claims that have the limitation of
'applying by vapor deposition a coating of pyrolytic carbon having a thickness within the
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range of 2-3 mm on the articulating surface and having a modulus of elasticity similar to
that of bone and articular cartilage."' Reply Br. at 6.
2. What Rathenow Teaches
Rathenow teaches that medically implantable devices can be coated with a
carbon-containing layer by at least partially coating the device with a polymer film and
thereafter heating the polymer film at high temperatures in the region of 200-2500 deg.
C in an atmosphere essentially free from oxygen. See Abstract, ~~ 24, 26 and 27, 154-
56 and claim 1. Rathenow consistently mentions that the invention involves the
application of a polymer film to a substrate with subsequent heating. The phrase
"polymer film" appears at numerous places throughout the specification (e.g., ~~ 36, 37,
39, 42-45, 47-49, 51-57, 59-62, 64-70, 74, 78, 98, 103, 13, 155, 156, 159-62, 168 and
169) and claims (e.g., claims 1, 4-7, 13 and 14).
The resultant carbon-containing layer is porous. The pores are suitable for
receiving "medical active principles" or "pharmacologically effective substances" such as
medicines and the like. See~~ 20-22, 84, 98, 99, 105-09, 113-15, 127, and 129. In the
specific case of orthopedic implants such as the present invention, the carbon-
containing layer(s) can be macroporous "in order to enhance an improved integration of
the implants by ingrowth into the surrounding cell tissue or bone tissue" and by
receiving various "active principles." Id.,~ 119-24.
Porosity or other surface properties can be influenced by additives such as
silicates, nano-particles, etc. Id., ~~ 53-55, 83 or by "after-treatments" such as oxidation
in air, boiling in oxidizing acids, etc. Id., ~ 85. Different film layers can be applied so that
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multi-layer coatings with layers of different porosity can be formed. Id.,~ 56. The
thickness of the carbon-containing layer can vary from 10-40 microns to thicker layers in
the millimeter to centimeter range. Id., ~ 69.
The use of chemical vapor deposition (CVD) to form carbon-coated stents is
mentioned as a known technique, but is stated to be undesirable for various reasons
such as difficult process conditions, thermal expansion incompatibilities, low level of
adhesion, cracks, etc. Id., ~~ 10-14. The undesirability of using CVD to apply a carbon
layer to a medical implant made of metal is confirmed by Example 6 (reference
example), in which a CVD coating was applied to a stainless steel test strip but the
coated test strip failed a TESA adhesive tape peel test (removal of tape "results in
clearly visible grey adhesions"). 1 Id., ~~ 140-41. Example 6 is noted as a "Reference
Example," which indicates that it is a prior art technique and not part of the invention. 2
1 TESA brand tape has been used for pee! adhesion tests. See The TESA Technology
Journal, Feb., 2013,
http://www. tesatape. com/featured/Tech nologyJou rnal_ 3233652/down load/6782681 /581
6667 /understand-peel-adhesion. pdf.
2 A "reference example" is not an example of the invention. A reference example is
prior art that is described in the specification for purposes of comparison and contrast
with the invention. See, for example, Kimura et al., US 9,243,029 82, iss. Jan. 26, 2016
(Reference Example 1 was a prior art description of how to obtain freeze-dried powder
of glutathione); Udayampalayam Palanisamy et al., US 2015/0246931, pub. Sept. 3,
2015 (In an improved process for the manufacture of Tazobactam, Reference Example
- 1 was described as "The process disclosed (example-1) in U.S. Pat. No. 4,925,934 ..
. to get Tazobactam.")
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Rathenow does not disclaim all use of CVD. CVD is mentioned as a "further
optional process step" to apply a "top coat" to the film -- but not directly to the substrate.
Id.,~~ 86, 87, 89-91 and claim 8. CVD precursors "deposit themselves in an essentially
evenly distributed manner in the pore system of the pyrolysed coating, modify the pore
structure therein and thus lead to an essentially homogeneous pore size and pore
distribution." Id., ~ 89. "[P]ores in the carbon-containing layer on the implant can be
reduced in size in a controlled manner until the pores are completely closed/sealed off."
Id.,~ 90.
~ The Board did not Address Rathenow's Specific
Teachings Concerning CVD Failures
The Board disagreed with appellants' argument that one skilled in the art would
not have relied on Rathenow for a teaching of using CVD to apply a layer of pyrolytic
carbon directly to a strong metal substrate such as titanium or stainless steel. Decision
at 7. !n so doing, the Board acknowledged that Rathenow pointed out certain
disadvantages of applying a coating by using CVD, but stated:
Id.
Rathenow also discloses an example in which chemical vapor deposition
is used to coat stainless steel with pyrolytic carbon and that it may be
necessary to apply a carbon vapor deposition process to a carbonizing
layer in certain circumstances .... Based on these disclosures, we
disagree that using a chemical vapor deposition process would render
Rathenow's product inoperative, as Appellants assert.
The example relied on by the Board is Example 6, which is stated by Rathenow
to be a Reference Example. Example 6 supports Rathenow's discussion of problems
likely to be encountered if CVD is applied directly to a metal substrate, because the
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product of Example 6 failed an adhesive tape pull test.
The Board also referred to~ 86 which discusses the use of CVD to treat a
carbonized coating with suitable precursor gases. A test of this procedure was
conducted by Rathenow and reported in Example 8 ("Titan, Refined with DVD"). As with
the stainless steel example of Example 6, the use of CVD to coat a carbonized layer
failed a TESA adhesive tape peel test. As noted by Rathenow in ~ 144, "[a] peel test ...
results in grey adhesions."
Thus, in both of the cases in which Rathenow used CVD, the resultant product
failed an adhesion test. The failure of the adhesion tests shows that Rathenow indeed
teaches away from the use of CVD to apply a pyrolytic carbon coating to a strong metal
substrate such as titanium or stainless steel.
4. In View of the CVD Failures. Rathenow Would Discourage
One Skilled in the Art From Using CVD to Apply Pyrolytic
Carbon Directly to a Strong Metal Substrate
Rathenow discloses that CVD could be used to add additional material to a
previously applied layer of porous, carbonized polymer film, but direct use of CVD on a
strong metal surface such as titanium or stainless steel would be ineffective since it
would fail an adhesive tape peel test. Even in the example where CVD was used to add
additional material to the carbonized polymer film layer, the resultant product failed an
adhesive tape peel test. In view of Rathenow's test results, one skilled in the art would
have been discouraged from using CVD to apply pyrolytic carbon directly to a strong
metal substrate such as titanium or stainless steel.
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Evidence that a reference discourages, or teaches away from, a proposed
modification supports a finding of non-obviousness. Santarus, Inc. v. Par
Pharmaceutical, Inc., 694 F.3d 1344, 1355 (Fed. Cir. 2012). "A reference 'teaches
away' when it 'suggests that the line of development flowing from the reference's
disclosure is unlikely to be productive of the result sought by the applicant."' Santarus,
supra, at 1354 (citations omitted).
This principle has been recognized by the Supreme Court: "[w]hen the prior art
teaches away from combining certain known elements, discovery of a successful means
of combining them is more likely to be nonobvious." KSR Int'/ Co. v. Teleflex, Inc., 550
U.S. 398, 416 (2007), citing United States v. Adams, 383 U.S. 39, 51-52 (1966) (prior
art warned that risks were involved in using the types of electrodes employed by the
inventor).
If CVD were to be used to apply a layer of pyrolytic carbon directly to a strong
metal substrate such as titanium or stainless steel, such usage of CVD would change
the principle of operation of Rathenow since Rathenow's invention resides in applying a
polymer film to the substrate. Usage of CVD also would render Rathenow ineffective for
its intended purpose, in part because the CVD layer could be expected to fail by not
adhering properly to the substrate.
If the proposed modification or combination of the prior art would change the
principle of operation of the prior art invention being modified, then the teachings of the
references are not sufficient to render the claims prima facie obvious. In re Ratti, 270
F.2d 810 (C.C.P.A. 1959) (claimed oil seal required resiliency of bore-engaging
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portions; prior art seal required rigidity of bore-engaging portions). Also, as noted by
appellants in their Reply Brief at 7, a reference cannot be modified to create an
obviousness rejection if the modification will render the reference unsatisfactory for its
intended purpose. In re Gordon, 733 F.2d 900 (Fed. Cir. 1984) (not permissible to
modify prior art filter assembly by turning it upside down to filter blood since that would
render it ineffective for its intended purpose of filtering gasoline and water).
§.:. The Board did not Consider the Obviousness
Issue Properly as Regards Rathenow
The Board stated that Rathenow discloses orthopedic implants with pyrolytic
carbon layers as well as the use of coatings "in the millimeter range to the centimeter
range." Decision at 5. The Board acknowledged that Rathenow's disclosure was in the
context of implants of full carbon materials, but stated that "Rathenow does not preclude
their use on implants with metal substrates as claimed." Id. at 6.
The obviousness issue revolves about what Rathenow teaches one ski!!ed in the
art, not whether Rathenow forbids the proposed combination. In other words, the
question is whether Rathenow's teaching of a thick, porous, polymer film coating for a
full carbon bone implant would lead one skilled in the art to apply a thick, non-porous,
CVD coating to a strong metal substrate such as titanium or stainless steel used as an
articulating surface.
Since Rathenow is silent on the combination of the claimed invention, it is wrong
to conclude that the claimed invention would have been obvious merely because
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Rathenow did not preclude it. To make an obviousness determination based on what
Rathenow did not preclude is a clear indication that impermissible hindsight analysis
was used.
§.,_ The Board did not Fully Take Into Account the Teachings of Bokros
Appellants argued that Bokros disclosed a "weak" substrate and thin pyrolytic
carbon coatings that would not withstand loads as would the claimed invention. App. Br.
at 16. The Board discussed Bokros' disclosure of a dense, polished wear surface,
Decision at 6-7, but did not take into account other portions of Bokros that "taught away"
from the claimed invention.
At col. 12, I. 13-43, Bokros discusses the shock-absorbing characteristics of
metal hip joint prostheses. Bokros' solution to the problem of excessive shock is to use
a weak carbon substrate ball 82 to which a thin coating of pyrolytic carbon is applied.
Bokros discloses a substrate made of polycrystalline graphite having a Young's
modulus of elasticity of 1.7 X 106 psi. Col. 9, I. 47-53. Bokros mentions that additional
cushioning in the form of an elastomer interlayer 92 may be desirable. Col. 12, I. 17-24.
These teachings of Bokros strongly suggest that the claimed invention would not
have been obvious, i.e., it would not have been obvious to apply a thick (2-3 mm) layer
of Bokros' pyrolytic carbon to a strong metal substrate such as titanium or stainless
steel. If using a 2-3 mm layer of pyrolytic carbon on a strong metal substrate would have
been obvious, then Bokros certainly would have done it since he was concerned about
the shock-absorbing characteristics of metal hip joint prostheses. Bokros' use of a weak
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carbon substrate coupled with a shock-absorbing elastomer layer confirms the non-
obviousness of the claimed invention.
L Conclusion
In view of the foregoing, appellants respectfully request that the affirmance of the
obviousness rejection of claims 1, 2, 4, 6-8, 10 and 13 under 35 U.S.C. § 103(a) be
reconsidered and reversed.
Law Offices of Wayne D. Porter, Jr.
6200 Rockside Woods Blvd. North
Suite 315
Independence, Ohio 44131
Telephone: (216) 373-5545
Facsimile: (216) 520-0313
April 11, 2016
Respectfully submitted,
/Wayne D. Porter. Jr./
Wayne D. Porter, Jr.
Reg. No. 26,977
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