Ex Parte Jang

Board of Patent Appeals and Interferences

Jul 31, 2007

10123883 (B.P.A.I. Jul. 31, 2007)

The opinion in support of the decision being entered today
is not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte DAVID G. JANG
____________

Appeal 2007-2331
Application 10/123,883
Technology Center 3700
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Decided: July 31, 2007
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Before TONI SCHEINER, ERIC GRIMES, and LORA M.
GREEN, Administrative Patent Judges.

GREEN, Administrative Patent Judge.

DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134 from the
Examiner’s final rejection of claims 24-31 and 41. We have jurisdiction
under 35 U.S.C. § 6(b). Claims 24 and 31 are representative of the claims
on appeal, and read as follows:
24. A stent having a longitudinal length, a compressed state and an
expanded state, the stent comprising:
a plurality of annular elements;
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Application 10/123,883

connecting members connecting the plurality of annular elements,
each connecting member comprising a bend;
the stent having a first segment and a second segment;
wherein the first and second segments have different diameters when
the stent is in the expanded state.

31. A stent having a compressed state and an expanded state, the stent
comprising:
a plurality of annular elements and bent connectors that define a
plurality of apertures;
the stent having a first segment and a second segment;
wherein the first and second segments have different diameters when
the stent is in the expanded state;
wherein all the apertures in the stent have a uniform size when in the
compressed state and the stent has a longitudinal length which remains the
same in both the compressed and expanded states.

The Examiner relies upon the following references:
Alt US 5,843,117 Dec.1, 1998
Savin US 4,950,227 Aug. 21, 1990

We affirm.

BACKGROUND
Angioplasty, according to the Specification, is one of the most
effective means of revascularization of stenosed vessels (Specification 1).
The procedure for intravascular stent placement typically
involves pre-dilation of the target vessel using balloon
angioplasty, followed by deployment of the stent, and
expansion of the stent such that the dilated vessel walls are
supported from the inside.
The intravascular stent functions as scaffolding for the
lumen of a vessel. The scaffolding of the vessel walls by the
stent serve to: (a) prevent elastic recoil of the dilated vessel
wall, (b) eliminate residual stenosis of the vessel; a common
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occurrence in balloon angioplasty procedures, (C) maintain the
diameter of the stented vessel segment slightly larger than the
native unobstructed vessel segments proximal and distal the
stented segment and (d) as indicated by the latest clinical data,
lower the restenosis rate. Following an angioplasty procedure,
the restenosis rate of stented vessels has proven significantly
lower than for unstented or otherwise treated vessels; treatments
include drug therapy and other methods mentioned previously.

(Id. at 1-2.)
The Specification also discloses a tapered stent, wherein the stent may
be tapered by removal of expansion struts, or by changing “the stiffness of
the stent struts, expansion struts, connecting struts or joining struts such that
the stiffness of the struts varies along the length of the stent.” (Id. at 12.) A
tapered balloon catheter is used to deliver and deploy the tapered stent (id.).
“Using a tapered balloon to expand a non-tapered stent will also achieve a
tapered expanded stent; however, since no metal is removed from the stent,
the stent is tapered as a result of incomplete expansion.” (Id. at 13.) Such a
stent, according to the Specification, has an increased metal fraction at the
tapered end, and thus an increased risk of acute thrombosis (id.).

DISCUSSION
Claims 24-31 and 41 stand rejected under 35 U.S.C. § 103(a) as being
obvious over the combination of Alt and Savin.1 As Appellant does not
argue the claims separately, we focus our analysis on independent claim 24.

1 In the Final Rejection at page 2, mailed May 2, 2006, the Examiner set
forth the statutory basis for 35 U.S.C. § 103(a), and then in the statement of
the rejection, cited 35 U.S.C. § 102(e). Appellant recognized that the
statement that the claims were rejected under 35 U.S.C. § 102(e) was a
typographical error, and that the Examiner in fact intended to reject the
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37 C.F.R. § 41.37(c)(1)(vii) (2006).
Alt is relied upon for teaching a stent (30) having a longitudinal
length, a compressed state and an expanded state, the stent comprising
a plurality of annular elements having straight struts of the
same length and apices; connecting elements of the same length
(70) connected to the apices of the annular elements (75) and
comprising a bend; and the length of the stent remains the same
in both the compressed and expanded states (Fig. 10 and col.
18, lines 42-62). Each strut has a longitudinal dimension,
which is smaller when the annular elements are in the expanded
state than in the compressed state and larger when in the
expanded state then [sic] in the compressed state (Fig. 10 and
Col. 18, lines 42-62). Adjacent annular elements of the stent
define a plurality of apertures, which have a geometric shape
and a uniform size when in the compressed state (Fig. 5a). The
first and second segments have different degrees of flexibility
(Col. 19, lines 10-12).

(Answer 3).
The Examiner acknowledges that “Alt does not disclose that the first
and second segments have different diameters when the stent is in the
expanded state[] and the same diameters when the stent is in the compressed
state.” (Id. at 4.)
Savin is relied upon by the Examiner for teaching “a stent delivery
system wherein the balloon can be tapered or stepped in order to expand the
stent in a tapered orientation.” (Id.) Savin is also relied upon for teaching
that configuration allows for delivery to coronary arteries, peripheral arteries
and visceral arteries, veins, and to the biliary tree, the urinary tract, and the
gastro-intestinal tract (id.). Savin also discloses that only a portion of the
claims under 35 U.S.C. § 103(a) (Br. 5-6). Thus, the statutory ground for
the rejection before is 35 U.S.C. § 103(a).
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stent can be positioned over the balloon, in which case only one end of the
stent is expanded, allowing the stent to act as a filter (id.).
The Examiner concludes:
It would have been obvious to one having ordinary skill
in the art at the time of the invention to use a tapered balloon to
deliver the stent of Alt, thereby providing a stent that has first
and second segments with different diameters in the expanded
state and the same diameters in the compressed state. Savin
states that the motivation for using a tapered balloon to deliver
a stent provides numerous advantages because it can be used in
various areas of the body and can also fulfill several functions
(i.e. a stent or a filter). Furthermore, Alt states that it is well
know[n] that the same type of stent could be delivered with
many different types of balloons depending on the patient, the
vessel diameter and the condition being treated (Col. 16, lines
24-30).

(Answer 4).
“In rejecting claims under 35 U.S.C. § 103, the examiner bears the
initial burden of presenting a prima facie case of obviousness. Only if that
burden is met, does the burden of coming forward with evidence or
argument shift to the applicant.” In re Rijckaert, 9 F.3d 1531, 1532,
28 USPQ2d 1955, 1956 (Fed. Cir. 1993) (citations omitted). In order to
determine whether a prima facie case of obviousness has been established,
we considered the factors set forth in Graham v. John Deere Co., 383 U.S.
1, 17 (1996); (1) the scope and content of the prior art; (2) the differences
between the prior art and the claims at issue; (3) the level of ordinary skill in
the relevant art; and (4) objective evidence of nonobviousness, if present.
We find that the Examiner has met his burden of setting forth a prima facie
case of obviousness, and the rejection is affirmed.
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Appellant argues that the stent taught by the combination of Alt and
Savin does not have an expanded state (Br. 6). Savin, according to
Appellant, teaches expanding only part of the device using the balloon, and
that “[t]o assert that a device which is partially unexpanded is in an
expanded state is to give the term ‘expanded state’ a meaning repugnant to
the definition of the term supported by the instant application.” (Br. 6.)
Appellant argues that “Savin’s partial inflation method does not disclose a
stent in its expanded state but rather a filter.” (Id. at 7.) Appellant argues
further that a stent as disclosed in the present application at page 2, lines 4-8,
“is a device used to scaffold a vessel wall and to remove obstructions from
within the vessel.” (Id.). A filter as disclosed by Savin, according to
Appellant, is partially inflated to provide a mechanism for filtering a body
cavity (id.). Appellant asserts that “[s]uch an arrangement does not scaffold
and support the vessel in the manner of a stent.” (Id. (emphasis in original).)
As noted by the Examiner, Savin does not just teach filters, but also
teaches methods of using tapered and stepped balloons to deliver stents to
coronary arteries, peripheral arteries and visceral arteries, veins, and to the
biliary tree, the urinary tract, and the gastro-intestinal tract (Savin, col. 6, ll.
30-34) (Answer 5). Thus, Savin teaches using a tapered or stepped balloon
to deliver a stent, and not just a filter as alleged by Appellant.
Moreover, claim 24 reads on a stent that has been partially expanded,
as well as fully expanded, by the tapered balloon. There is nothing in claim
24 that requires the entire stent to be in a fully expanded state. Our mandate
is to give claims their broadest reasonable construction. In re American
Academy of Science Tech Center, 367 F.3d 1359, 1364, 70 USPQ2d 1827,
1830 (Fed. Cir. 2004). “An essential purpose of patent examination is to
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fashion claims that are precise, clear, correct, and unambiguous. Only in this
way can uncertainties of claim scope be removed, as much as possible,
during the administrative process.” In re Zletz, 893 F.2d 319, 322, 13
USPQ2d 1320, 1322 (Fed. Cir. 1989).
We acknowledge that the Specification teaches that a stent that is
tapered as a result of incomplete expansion has an increased risk of acute
thrombosis (Specification 13), but that appears to be only a non-preferred
embodiment, and not outside the scope of the claimed invention. We
decline to read limitations from the Specification into the claims, a practice
that the Court of Appeals for the Federal Circuit, our reviewing court,
cautions against. See SuperGuideCorp. v. DirecTV Enterprises, Inc.,
358 F.3d 870, 875, 69 USPQ2d 1865, 1868-69 (Fed. Cir. 2004) (“Though
understanding the claim language may be aided by explanations contained in
the written description, it is important not to import into the claim limitations
that are not part of the claim. For example, a particular embodiment in the
written description may not be read into a claim when the claim language is
broader than the embodiment.”).
CONCLUSION
In summary, we conclude that the Examiner has set forth a prima
facie case of obviousness, and the rejection of claims 24-31 and 41 under
35 U.S.C. § 103(a) as being obvious over the combination of Alt and Savin
is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
AFFIRMED

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