Ex Parte Wei et al

Board of Patent Appeals and Interferences

Mar 20, 2012

11157132 (B.P.A.I. Mar. 20, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte I-CHIEN WEI, KUNG-HSING LEE, HSIEN-MING HUNG,
NING TSAO, MENG-HUI HSU, SHAN-YING LIN,
and YA-HUI HUANG
____________

Appeal 2011-009918
Application 11/157,132
Technology Center 1600
____________

Before DONALD E. ADAMS, DEMETRA J. MILLS, and
STEPHEN WALSH, Administrative Patent Judges.

ADAMS, Administrative Patent Judge.

DECISION ON APPEAL

This appeal under 35 U.S.C. § 134 involves claims 1-11, 18-27, 34-
49, and 56-67. We have jurisdiction under 35 U.S.C. § 6(b).
STATEMENT OF THE CASE
The claims are directed to a chemically modified
polyaminosaccharide (claims 1-11 and 18); a process for producing a
chemically modified polyaminosaccharide (claims 19-27 and 34-40); a
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composition comprising a chemically modified chitosan and sulfur (claims
41-49 and 56-59); a product manufactured using the composition of claim 41
(claims 60-62); and a method of promoting wound healing in a mammal in
need of such treatment (claims 63-67). Claims 1 and 63 are representative
and are reproduced in “Appendix A” of Appellants’ Brief (App. Br. 13 and
23).
Claims 1-4, 18-21, 34-36, 39, 41, 42, 44, 45, 56, and 58-60 stand
rejected under 35 U.S.C. § 102(b) as being anticipated by Maresch.
1

Claims 1-11, 18-27, 34-39, and 56-62 stand rejected under 35 U.S.C.
§ 103(a) as unpatentable over the combination of Maresch, Jung,
2
and
Lohmann.
3

Claims 63-67 stand rejected under 35 U.S.C. § 103(a) as unpatentable
over the combination of Gouda,
4
Malette,
5
Chen,
6
and Maresch.
We reverse.

Anticipation:
ISSUE
Does the preponderance of evidence on this record support
Examiner’s finding that Maresch teaches Appellants’ claimed invention?

1
Maresch et al., DE 3432227, published March 13, 1986, as translated in
PTO 07-6197.
2
Chung, KR 0163098, published October 22, 1996, as translated in
PTO 07-438 (Jung).
3
Lohmann et al., US 5,708,152, issued January 13, 1998.
4
Gouda et al., US 5,902,798, issued May 11, 1999.
5
Malette et al., US 4,532,134, issued Jul. 30, 1985.
6
Chee-Shan Chen, Antibacterial Effects of N-Sulfonated and N-Sulfobenzoyl
Chitosan and Application to Oyster Preservation, 61(9) J. FOOD PROTECTION
1124-1128 (1998).
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FACTUAL FINDINGS (FF)
FF 1. Appellants disclose that known processes involving the addition of a
sulfonic acid group to polyaminosaccharide molecules “oftentimes resulted
in serious degradation of the starting materials,” “tend to produce a pool of
modified polyaminosaccharides with high variability in important
properties,” and “their use in applications benefiting from precise knowledge
of polyaminosaccharide properties is either severely curtailed or requires
additional processing” (Spec. 1: 25 - 2: 7; see also id. at 3: 22 - 4: 2).
FF 2. Chitosans are polyaminosaccharides within the scope of the claimed
invention (Spec. 12: 17-20; see also Spec. 13: 9-12).
FF 3. Appellants disclose that
[W]hen a chitosan was sulfonated based on the aforesaid
processes, a predominant portion of bonding between the amino
groups thereof and the alkyl sultone is actually ionic bonding,
which can be readily disrupted by changes in the chemical
environment. Although covalent bonding, . . . might occur, it is
infrequent and does not represent a significant portion of the
bonding between the amino groups of chitosan and the alkyl
sultone.

(Spec. 4: 2-8.)
FF 4. Appellants disclose that Maresch teaches a process for the
preparation of alkyl sulfonated chitin, wherein
[O]ne can obtain a composition of heterogeneous alkali
chitin/chitosan molecules having a diversity of substitution
patterns (i.e., the 1,3-propane sultone might be attached to
either one or both of the -NH2 group and -CH2OH group of
each saccharide monomer of alkali chitin/chitosan molecules,
and acetyl groups might still remain in some saccharide
monomers).

(Spec. 5: 3-8.)
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FF 5. Appellants disclose that they
[F]ound from experimentation that when chitosan is chemically
modified by 1,3-propane sultone in the presence of isopropanol
at 25°C for 24 hrs[.] [as taught by Maresch], the recovered
product ha[d] no significant increase in weight, indicating no or
very low attachment of 1,3-propane sultone to the saccharide
monomers of chitosan molecules.

(Spec. 5: 24 - 6: 1.)
FF 6. Appellants disclose that when Maresch’s
[S]ulfonation reaction was conducted at 45°C for 48 hrs[.],
while the recovered product has an increase in weight, it will
form a gel-like product when treated with an ammonia
solution(eq), . . . it is very likely that the sulfopropyl derivatives
of chitosans produced . . . have molecular structures in which
the sulfopropyl groups derived from 1,3-propane sultone are
attached to the free amino groups primarily via ionic bonding
instead of covalent bonding.

(Spec. 6: 1-10.)
FF 7. Lee declares that the results of a comparative test of the claimed
invention against Maresch “attest[ ] to the criticality of the reaction
temperature” and support Appellants’ disclosure regarding Maresch (Lee ’09
Declaration
7
1: ¶ 3 – 2: ¶ 5; Cf. FF 3-5).
FF 8. Appellants disclose that they
[F]ound than an un-modified polyaminosaccharide having
amino functional groups could be sulfonated by a hydrocarbyl
sultone compound in the presence of an organic solvent under a
suitable temperature to form a chemically modified
polyaminosaccharide, in the molecular structure of which a
predetermined proportion of the amino functional groups is

7
Declaration of Kung-Hsing Lee, executed August 24, 2009.
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sulfonated by the hydrocarbyl sultone compound via a covalent
bond.

(Spec. 11: 5-11 (emphasis added).)
FF 9. Appellants disclose that they
[S]urprisingly found that, since the sulfonation reaction
according to this invention was carried out in the presence of a
selected organic solvent under a suitable temperature, it greatly
favors the attachment of the hydrocarbyl sultone compound to
the -NH2 group than the -CH2OH group on each saccharide
monomer of chitosan molecules.

(Spec. 13: 19-23; see also Spec. 15: 13-15 (“The hydrocarbyl sultone
compound normally reacts almost exclusively with the amino functional
groups of the un-modified polyaminosaccharide, with little to no reaction
with the hydroxy groups”).)
FF 10. Appellants disclose that “the reflux temperature of the organic
solvent . . . is usually higher than 45°C” (Spec. 13: 25-26).
FF 11. Appellants disclose that while “[i]onic bonds are the most common
type of bonds formed in many previous processes” Appellants’ “invention
may result in at least 50%, at least 60%, at least 70%, at least 80%, at least
90%, at least 95%, or at least 98% of sultone-amino group bonds being
covalent bonds” (Spec. 15: 19-23).
FF 12. Appellants disclose that according to their invention the “amount of
the hydrocarbyl sultone compound relative to the number of moles of the
amino functional groups of the un-modified polyaminosaccharide is
controlled so that the recovered chemically modified polyaminosaccharide
has a predetermined degree of sulfonation ranging from 5% to at least 90%”
(Spec. 17: 22-27).
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FF 13. Examiner finds that Maresch teaches “the preparation of alkyl
sulfonated chitin obtained via the reaction of chitin (polyaminosaccharide)
with 1,3-propyl sultone at 25°C using isopropanol as the solvent” (Ans. 3).
FF 14. Examiner finds that “Maresch presents a structure that is seen to
have covalent bonding according to chemical convention. It need not be
described further as covalent bonding” (Ans. 9; see also Spec. 4: 11-19).
ANALYSIS
Appellants’ disclosure establishes that chemically modified
polyaminosaccharides, such as chitosan, may vary depending upon the
method in which they are produced (FF 1-12). In this regard, Appellants’
disclose that their choice of solvent and reaction temperature favors the
attachment of the hydrocarbyl sultone compound to the -NH2 group rather
than the -CH2OH group on each saccharide monomer of chitosan molecules
(FF 9).
Appellants’ product-by-process claim 1 is drawn to “[a] chemically
modified polyaminosaccharide comprising a polyaminosaccharide and
sulfur, the chemically modified polyaminosaccharide capable of suppressing
the depletion of the sulfur content to no more than 3% by weight upon being
subjected to the treatment of an alkaline solution” that is produced by the
process of Appellants’ claim 19 (Claim 1; Cf. Claim 19). Appellants’
composition claim 41 is drawn to a composition comprising a chemically
modified polyaminosaccharide comprising a polyaminosaccharide and
sulfur, the composition capable of suppressing the depletion of the sulfur
content to no more than 3% by weight upon being subjected to the treatment
of an alkaline solution” that is produced by the process of Appellants’ claim
19 (Claim 41; Cf. Claim 19). The product of Appellants’ claim 60 is
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“manufactured using the composition of claim 41” (Claim 60). Thus, each
of Appellants’ claims relate to a process that makes use of an organic
solvent selected from a defined set of organic solvents, wherein the
polyaminosaccharide is modified in a reaction performed under a reflux
temperature of the organic solvent.
Examiner finds that Maresch teaches “the preparation of alkyl
sulfonated chitin obtained via the reaction of chitin (polyaminosaccharide)
with 1,3-propyl sultone at 25°C using isopropanol as the solvent” (FF 13; Cf.
FF 4; see generally FF 1-3 and 5-12). While Examiner recognizes that
Maresch’s reaction is performed at 25°C with isopropanol as the organic
solvent, Examiner does not dispute Appellants’ contention that 25°C “is well
below the reflux temperature[ ] of . . . isopropanol – reflux temperature 82-
85°C” (App. Br. 9; see also FF 10). Accordingly, Maresch fails to teach the
process of Appellants’ claim 19, which requires, inter alia, “alkylsulfonating
the un-modified polyaminosaccharide by adding a hydrocarbyl sultone
compound to the mixture under a reflux temperature of the organic solvent”
(Claim 19).
Further, as discussed above, Appellants disclose and Lee declares that
reaction temperature is critical for obtaining the modified
polyaminosaccharide of their claimed invention (FF 7-11). In particular,
Appellants disclose that the degree and type of bonding between the amino
groups of chitosan and the alkyl sultone is variable among different methods
of producing chemically modified polyaminosaccharides (FF 3-8 and 11).
Appellants also disclose that the “diversity of substitution patterns (i.e., the
1,3-propane sultone might be attached to either one or both of the -NH2
group and -CH2OH group of each saccharide monomer of alkali
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chitin/chitosan molecules, and acetyl groups might still remain in some
saccharide monomers)” is related to the method used to produce chemically
modified polyaminosaccharides (FF 4 and 9). Nevertheless, Examiner finds
that since “Maresch presents a structure that is seen to have covalent
bonding according to chemical convention. It need not be described further
as covalent bonding” (Ans. 9; see also Spec. 4: 11-19). We are not
persuaded.
We recognize that Appellants can be required to prove that prior art
products do not necessarily or inherently possess the characteristics of the
claimed product when the “prior art products are identical or substantially
identical, or are produced by identical or substantially identical processes”
In re Best, 562 F.2d 1252, 1255 (CCPA 1977). However, an important first
step in shifting the evidentiary burden under Best, falls on Examiner to
establish that the prior art products are identical or substantially identical or
are produced by identical or substantially identical processes (Cf. id.; see
also App. Br. 6). For the reasons discussed above, Examiner failed to
establish that Maresch’s process is identical or substantially identical to
Appellants. Further, given that the degree of covalent bonding and the
location of this bonding can vary depending upon the method used to
produce the modified polyaminosaccharide, we find that Examiner failed to
establish that a person of ordinary skill in this art would have reasonably
expected that Maresch’s modified polyaminosaccharide is identical or
substantially identical to Appellants’.
In sum, weighing the preponderance of evidence on this record, we
find that the weight of the evidence falls in favor of Appellants. To be
complete, we recognize Examiner’s critique of the Lee ’09 Declaration and
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find Examiner’s critique to further support a conclusion that chemically
modified polyaminosaccharides vary depending upon their method of
production (see Ans. 9).
CONCLUSION OF LAW
The preponderance of evidence on this record fails to support
Examiner’s finding that Maresch teaches Appellants’ claimed invention.
The rejection of claims 1-4, 18-21, 34-36, 39, 41, 42, 44, 45, 56, and 58-60
under 35 U.S.C. § 102(b) as being anticipated by Maresch is reversed.

Obviousness:
The rejection over the combination of Maresch, Jung, and Lohmann:
ISSUE
Does the preponderance of evidence on this record support a
conclusion of obviousness?
FACTUAL FINDINGS (FF)
FF 15. Examiner relies on Maresch as discussed above.
FF 16. Examiner finds that Maresch fails to suggest “the use of solvents
other than isopropanol and the use of sultones other than 1,3-propane sultone
as [the] sulfonating agent” (Ans. 5).
FF 17. Examiner relies on Lohmann to suggest a process for producing
alkylsulfonated chitosans using ethers and ether alcohols as solvents and
sulfonating agents other than 1,3-propane sultone (id.).
FF 18. Examiner relies on Jung to suggest heating the reaction mixture
before alkylation and the use of polyaminosaccharide derivatives “in making
medicinal, food and cosmetic products” (Ans. 5-6).
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FF 19. Lee declares that Jung suggests an ionically bonded product (Lee ’10
Declaration;
8
App. Br. 9).
ANALYSIS
Based on the combination of Maresch, Jung, and Lohmann, Examiner
concludes that, at the time of Appellants’ claimed invention, it would have
been prima facie obvious to a person of ordinary skill in this art “to make the
modified polyaminosaccharides, compositions comprising them and use the
process of the prior art to make the alkylsufonated polyaminosaccharides
since the process conditions, steps and reagents for the same are seen to be
taught in the prior art” (Ans. 5). We are not persuaded.
Examiner fails to identify a suggestion in the prior art of performing a
reaction at the reflux temperature of the organic solvent as is required by
Appellants’ claimed invention. Accordingly, Examiner failed to establish
that the combination of references relied upon suggest the process of
Appellants’ claim 19. In addition, given that chemically modified
polyaminosaccharides vary depending upon their method of production,
Examiner failed to establish that the chemically modified
polyaminosaccharide produced by the method suggested by the combination
of Maresch, Jung, and Lohmann would have been expected to be the same as
Appellants claimed chemically modified polyaminosaccharide or a
composition comprising it. In sum, Examiner failed to establish an
evidentiary basis on this record to support a conclusion that “the disclosure
of Maresch and Jung . . . [suggest an] alkylsulfonated chitosan that has
covalent bonding” (Ans. 11; see App. Br. 10).

8
Declaration of Kung-Hsing Lee, executed February 6, 2010.
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CONCLUSION OF LAW
The preponderance of evidence on this record fails to support a
conclusion of obviousness. The rejection of claims 1-11, 18-27, 34-39, and
56-62 under 35 U.S.C. § 103(a) as unpatentable over the combination of
Maresch, Jung, and Lohmann is reversed.

The rejection over the combination of Gouda, Malette, Chen, and Maresch:
ISSUE
Does the preponderance of evidence on this record support a
conclusion of obviousness?
FACTUAL FINDINGS (FF)
FF 20. Examiner relies on Gouda to suggest “a method of promoting wound
healing comprising applying to the wound a composition comprising
chitosan” (Ans. 6).
FF 21. Examiner relies on Malette to suggest “a method of inhibiting
fibroplasia and promoting tissue regeneration in vascular grafts using
chitosan” (id.).
FF 22. Examiner finds that “Gouda and Malette do not teach the use of
alkylsulfonated chitosan in their method” (id.).
FF 23. Examiner relies on Chen to suggest “that sulfonated chitosans show
a wide spectrum of antibacterial effects with minimum inhibitory
concentrations being in the parts per million range” (id. at 6-7).
FF 24. Examiner finds that Chen “do[es] not teach alkylsulfonated
polyaminosaccharides” (id. at 7).
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FF 25. Examiner relies on Maresch to suggest “alkyl-sulfonated
polyaminosaccharides made by a process as instantly claimed. The structure
of the products should be the same as instantly claimed” (id.).
ANALYSIS
Based on the combination of Gouda, Malette, Chen, and Maresch,
Examiner concludes that, at the time of Appellants’ claimed invention, it
would have been prima facie obvious to a person of ordinary skill in this art
“to make the compounds as instantly [claimed] and use them in a method as
instantly claimed in order to look for analogs that may be more potent than
chitosan” (Ans. 7). Appellants contend that Gouda, Malette, and Chen fail
to “remedy the defects of Maresch” (App. Br. 11). We agree, for the
reasons set forth above with regard to Maresch (Cf. FF 20-25).
CONCLUSION OF LAW
The preponderance of evidence on this record fails to support a
conclusion of obviousness. The rejection of claims 63-67 under 35 U.S.C.
§ 103(a) as unpatentable over the combination of Gouda, Malette, Chen, and
Maresch is reversed.

REVERSED

cdc