Dow Global Technologies LLC

Patent Trials and Appeals Board

Oct 21, 2021

2021000344 (P.T.A.B. Oct. 21, 2021)

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.
14/421,072 02/11/2015 Oliver Petermann DI72380-US-PCT 7737
171313 7590 10/21/2021
DDP Nutrition & Biosciences
DUPONT LEGAL PATENT RECORDS CENTER
CHESTNUT RUN PLAZA 721/2340
974 CENTRE ROAD, P.O. BOX 2915
WILMINGTON, DE 19805
EXAMINER
MILLIGAN, ADAM C
ART UNIT PAPER NUMBER
1612
NOTIFICATION DATE DELIVERY MODE
10/21/2021 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
NBPTOLegal@iff.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte OLIVER PETERMANN, MATTHIAS SPREHE, and
STEVEN J. GUILLAUDEU
Appeal 2021-000344
Application 14/421,072
Technology Center 1600
Before JOHN E. SCHNEIDER, DEBRA L. DENNETT, and
RACHEL H. TOWNSEND, Administrative Patent Judges.
TOWNSEND, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims to a hydroxypropyl methyl cellulose
acetate succinate as being obvious and for nonstatutory double patenting.
We have jurisdiction under 35 U.S.C. § 6(b).

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42(a). Appellant identifies the real party in interest as “DDP Specialty
Electronic Materials US, Inc. which is the assignee of the present patent
application and a subsidiary of Rohm and Haas Electronic Materials CMP
Inc. which is a subsidiary of DuPont de Nemours, Inc.” (Appeal Br. 2.)
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We reverse the obviousness rejections, but affirm the nonstatutory
double patenting rejection.
STATEMENT OF THE CASE
Appellant’s Specification discloses that “[h]ydroxyalkyl methyl
cellulose acetate succinates [(HPMCAS)s], their uses and processes for
preparing them are generally known in the art,” including those made by
Shin-Etsu Chemical Co., known by the trade name AQOAT. (Spec. 1.)
Appellant’s Specification further discloses that HPMCASs are used as
enteric coatings in pharmaceutical dosage forms. (Id.)
Appellant’s Specification discloses that there are levels of turbidity in
organic solvents, e.g., having undissolved particles present when dissolved
in organic solvent, that are undesirable. (Id. at 2.) For example, the
Specification states “increase turbidity” is “undesirable when a hydroxyalkyl
methyl cellulose acetate succinate is subjected to spray-drying because of an
increased tendency to clogging devices used for spray-drying, such as spray
nozzles.” (Id.) In addition, the Specification states, “an increased amount of
undissolved particles in organic solvents is also undesirable when the
esterified cellulose ethers are used in transparent films or coatings.”
(Id.) Appellant’s invention is directed to HPMCAS having a certain weight
average molecular weight range, a particular weight percent range of
succinoyl groups, a maximum viscosity, and a maximum turbidity. (Id. at
4.)

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Claims 1, 4, 6, 7, 9, 10, 14–17, 20, 21, and 26–29 are on appeal.2
Claims 1 and 4, reproduced below, are illustrative of the claimed subject
matter:
1. A hydroxypropyl methyl cellulose acetate succinate
a) having from 4.0 to 8.0 weight percent of succinoyl
groups and from 10.0 to 14.0 weight percent of acetyl
groups,
b) having a weight average molecular weight Mw of from
80,000 Dalton to 350,000 Dalton, measured by SEC-
MALLS using as mobile phase a mixture of 40 parts by
volume of acetonitrile and 60 parts by volume of aqueous
buffer containing 50 mM NaH2PO4 and 0.1 M NaNO3,
c) exhibiting a turbidity of up to 37 NTU as a 1.5 weight
percent solution in acetone, measured according to
USEPA method 180.1, and
d) having a viscosity of up to 4.0 mPa.s, measured as a 2.0
wt% solution of the hydroxypropyl methyl cellulose
acetate succinate in 0.43 wt.-% aqueous NaOH at 20 °C
according to an Ubbelohde measurement according to
DIN 51562-1:1999-01.
4. A hydroxypropyl methyl cellulose acetate succinate
a1) having from 10.0 to 14.0 weight percent of succinoyl
groups and from 7.0 to 11.0 weight percent of acetyl
groups, or a2) from 14.0 to 18.0 weight percent of
succinoyl groups and from 5.0 to 9.0 weight percent of
acetyl groups,
b) having a weight average molecular weight Mw of from
80,000 Dalton to 350,000 Dalton, measured by SEC-
MALLS using as mobile phase a mixture of 40 parts by
volume of acetonitrile and 60 parts by volume of aqueous
buffer containing 50 mM NaH2PO4 and 0.1 M NaNO3,

2 Claims 11–13, 18, and 19 remain pending but are withdrawn from
consideration.
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Application 14/421,072

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c) exhibiting a turbidity of up to 33 NTU as a 1.5 weight
percent solution in acetone, measured according to
USEPA method 180.1, and
d) having a viscosity of up to 4.0 mPa.s, measured as a 2.0
wt% solution of the hydroxypropyl methyl cellulose
acetate succinate in 0.43 wt.-% aqueous NaOH at 20 °C
according to an Ubbelohde measurement according to
DIN 51562-1:1999-01.
(Appeal Br. 28.)
The prior art relied upon by the Examiner is:
Name Reference Date
Allaire US 2003/0228470 A1 Dec. 11, 2003
Ramji US 2004/0202698 A1 Oct. 14, 2004
Curatolo EP 0901786 A2 Mar. 17, 1999
Shin-Etsu Chemical
Co., Ltd.
NF Hypromellose
Acetate Succinate,
Shin-Etsu AQOAT
(Product Specification)
Oct. 2005

The following grounds of rejection by the Examiner are before us on
review:
Claims 1, 4, 6, 7, 9, 10, 14–17, 20, 21, and 26–29 under 35 U.S.C.
§ 103(a) as unpatentable over Shin-Etsu, Ramji, Allaire, and Curatolo.
Claims 1, 4, 6, 7, 9, 10, 14–17, 20, 21, and 26–29 under 35 U.S.C.
§ 103(a) as unpatentable over Curatolo.
Claims 1, 4, 6, 7, 9, 10, 14–17, 20, 21, and 26–29 under the ground of
nonstatutory double patenting as unpatentable over claims 1–15 of US
9,320,799 and Curatolo.

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DISCUSSION
I. Non-Obviousness
The Examiner found that the AQOAT Grade H product by Shin-Etsu
is a hydroxypropyl methyl cellulose acetate succinate (HPMCAS) that has
4–8% succinoyl groups and 10–14 % acetyl groups and that the AQOAT
Grade L product by Shin-Etsu is a HPMCAS that has 14–18% succinoyl
groups and 5–9 % acetyl groups. (Final Action 4.) The Examiner further
found that Shin-Etsu teaches both grades are made by introducing acetyl and
succinoyl groups to the hydroxyl groups of a hydroxypropyl methyl
cellulose (HPMC) backbone and that modifying the degree of substitution of
these groups changes the properties of the HPMCAS produced. (Id.)
The Examiner found that Shin-Etsu does not teach the type of HPMC
starting material used but that it would have been obvious to one having
ordinary skill in the art to have used a commercially available one such as is
taught by Ramji (Methocel®E3LV, which has a viscosity of about 3 mPas
using the Ubbelohde tube viscometer technique). (Final Action 5.) The
Examiner found that Allaire teaches that Methocel cellulose can be made
into ethers. (Id.)
The Examiner found that Curatolo teaches that HPMCAS may be
synthesized by treating HPMC with acetic anhydride and succinic anhydride
to produce HPMCAS in which acetyl groups are present in the range of 3 to
20 wt% and succinyl groups are present in the range of 2 to 30 wt%. (Id.)
The Examiner determined that it would have been obvious to one of
ordinary skill in the art to choose Methocel®E3 LV as a commercially
available HPMC polymer and add sufficient acetyl and succinoyl groups as
taught by Curatolo to achieve the desired properties as taught by Shin-Etsu.
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(Id. at 5–6.) The Examiner concluded that there would have been a
“reasonable expectation that the resulting HPMCAS polymer would have the
functional properties instantly claimed (including low turbidity) based on
having the same backbone and same substituents.” (Id. at 5.)
The Examiner further found “[i]n the case where the claimed ranges
overlap or lie inside ranges disclosed by the prior art (i.e. Curatolo), a prima
facie case of obviousness exists. See MPEP 2144.05.” (Id. at 6.) Moreover,
the Examiner found that “[w]here less turbidity is desired, one of ordinary
skill in the art would find it obvious to choose amounts from the low end of
the ranges taught by Curatolo to minimize potential cross-linking.” (Id.)
The Examiner also found that Curatolo alone renders the claimed
HPMCAS obvious because Curatolo teaches ranges of acetyl groups and
succinyl groups of the HPMCAS that overlap with the claimed ranges and
teaches that the HPMCAS “preferably . . . has a molecular weight in the
range of 10K to 400K.” (Final Action 6 (citing Curatolo ¶¶ 34, 43).)
Besides noting the overlapping ranges of acetyl and succinyl groups renders
the claimed HPMCAS prima facie obvious, the Examiner concluded “where
all the structural recitations are met by the prior art, there is a reasonable
expectation that the recited functional limitations are also met given that a
polymers function is a product of its structure.” (Id. at 6–7.)
We find that the evidence of record does not support the Examiner’s
conclusion of obviousness. In particular, we agree with Appellant that
evidence of record establishes that “HPMCAS having similar or same acetyl
and succinoyl contents can have significantly different turbidity in acetone”
and having acetyl and succinoyl groups within the claimed range does not
necessarily result in the turbidity claimed. (Appeal Br. 9–10 (citing Spec.
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Table 2); see also Reply Br. 4.) In particular, Appellant explains that with
respect to claim 1,
Shin[-]Etsu Grade H HPMCAS commercial product was
analyzed in the Comparative Example M. (See specification of
the present application, page 26, lines 27-32 bridging to page
27, lines 1-7). It has a turbidity of 42.4 NTU which is
significantly higher than [the] one (≤ 37) recited in claim 1.
(See specification of the present application, page 31, Table 2).
(Appeal Br. 10.) With respect to claim 4, Appellant explains
Shin[-]Etsu Grade L and Grade M HPMCAS commercial
products were analyzed in the Comparative Examples K and L
respectively. (See specification of the present application, page
26, lines 27-32 bridging to page 27, lines 1-7). Shin[-]Etsu
Grade L product has a turbidity of 39.4 NTU, and Shin[-]Etsu
Grade M product has a turbidity of 43.7 NTU. (See
specification of the present application, page 31, Table 2). Both
are significantly higher than [the] one (≤ 33) recited in claim 4.
(Id. at 13.)
It is certainly true that the prior art teaches that the degree of
substitution of the two types of ether substituents of HPMCAS (methyl and
2-hydroxypropyl) and the two types of ester substituents of HPMCAS
(acetyl and succinyl) “can be varied over a wide range to effect the chemical
and physical properties of the polymer.” (Curatolo ¶ 34.) Curatolo is
focused on optimizing the structure of HPMCAS “to obtain good
performance with a particular drug of interest.” (Id.) Curatolo explains that
different structures affect “obtaining and sustaining supersaturation [of a
drug] in in vitro tests and obtaining high bioavailability [of a drug] in vivo
. . . depending on the specific chemical and physical properties of the drug to
be delivered.” (Id.) Curatolo describes a preferred mean weight average
molecular weight range (Id. ¶ 34) and describes a range for the degree of
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substitution of the ether groups of HPMCAS and the ester groups (Id. ¶ 43),
but Curatolo does not provide any teaching or suggestion regarding turbidity
of the polymer, how it could be changed or why one would want to change
that variable.3 None of the other prior art relied upon by the Examiner
provides any insight in that regard either.
Appellant’s Specification explains that (1) the higher the turbidity in
acetone solution, the higher amount of undissolved particles, and (2)
increased turbidity is an undesirable property to the extent HPMCAS is
subjected to spray-drying. (Spec. 2.) Appellant’s Specification indicates
that clogging of the spray nozzle tends to increase with higher turbidity.
(Id.) Appellant’s Specification further indicates that “an increased amount
of undissolved particles in organic solvents is also undesirable when the
esterified cellulose ethers are used in transparent films or coatings.” (Id.) In
other words, Appellant’s Specification teaches there is a real world
practicality to a turbidity requirement.
We agree with Appellant that neither Curatolo nor the other prior art
relied upon by the Examiner recognizes turbidity of HPMCAS as a results
effective variable for optimization. (Appeal Br. 11.) “[D]iscovery of an
optimum value of a result effective variable in a known process is ordinarily

3 The Examiner states that “Curatolo prefers that the HPMCAS is soluble
[e.g. 0012].” (Ans. 8.) However, Curatolo describes a dispersion of
sparingly soluble drug and HPMCAS in a solvent in which the drug and
HPMCAS are soluble. (Curatolo ¶¶ 14, 19.) This does not teach or suggest
anything with regard to changing the solubility of HPMCAS, rather it
suggests that different solvents may need to be tried to solubilize HPMCAS.
(Id. ¶ 14 (“forming a solution comprising (i) HPMCAS, (ii) a sparingly
water-soluble drug, and (iii) a solvent in which both
(i) and (ii) are soluble”).)
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within the skill of the art.” In re Boesch, 617 F.2d 272, 276 (CCPA 1980).
Unlike in Boesch, the Examiner has not established that the property
asserted to be obvious to be optimized was recognized in the art to be
manipulatable in a particular and predictable way. Furthermore, the
evidence of record establishes that selecting the percentages specifically
described by Shin-Etsu does not result in HPMCAS having the claimed
turbidity. Coupled with the fact that the evidence of record establishes that
simply picking percentages of acetyl and succinyl groups within the range
disclosed by Curatolo will not necessarily result in the claimed turbidity, and
that even similar percentages do not necessarily result in the claimed
turbidity, we agree with Appellant that the Examiner has failed to provide
sufficient evidence to support the position that HPMCAS with the claimed
turbidity attribute would have reasonably been expected by simply picking
percentages of acetyl and succinyl groups within the claimed range disclosed
by Curatolo.
For the foregoing reasons, we do not affirm either one of the
Examiner’s obviousness rejections.

II. Nonstatutory Double Patenting
The Examiner’s nonstatutory double patenting rejection relies on the
position that Curatolo “teaches ranges which overlap with the instantly
recited structural limitations as well as motivation to modify the amount
within the ranges to change the properties of the polymer.” (Final Action
10.) However, for the reasons just discussed, we disagree with the Examiner
that Curatolo would have suggested to one of ordinary skill in the art to
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modify the ester groups of the HPMCAS of the claims of the ’799 patent and
achieve the claimed turbidity.
Nevertheless, we note that the Examiner’s position that just because
the claims of the ’799 patent do not recite the NTU limitation, i.e., the
turbidity limitation (Final Action 10) is not sufficient to demonstrate the
claims are patentably distinct from the claims on appeal. Appellant has not
established that HPMCAS described by the claims of the ’799 patent do not
also have the claimed maximum turbidity. Instead, Appellant simply argues
that the claims of the ’799 patent do not recite the acetyl and succinoyl
contents, molecular weight, turbidity, and viscosity recited in the claim and
as such the claim is patentably distinct. (Appeal Br. 22.)
Nonstatutory double patenting was borne out of 35 U.S.C.
§ 101, not § 103. Specifically, § 101 precludes more than one
patent on the same invention. [The Court of Customs and
Patent Appeals], concerned that applicants could evade the
§ 101 requirement by drafting claims that “vary slightly from
the earlier patent,” fashioned the doctrine of nonstatutory
double patenting “to prevent issuance of a patent on claims that
are nearly identical to claims in an earlier patent.”
Eli Lilly & Co. v. Teva Pharms. USA, Inc., 619 F.3d 1329, 1341 (Fed. Cir.
2010). “The primary inquiry in double patenting cases is therefore whether
the claims in the latter patent are more than a ‘slight variant’ from the claims
in the earlier patent.” Id. That the ’799 patent claims do not specifically
recite the acetyl and succinoyl contents, molecular weight, turbidity, and
viscosity recited in the claims on appeal does not establish that they are not
inherent to the HPMAC structure claimed in the ’799 patent. Thus, for this
reason, we affirm the Examiner’s rejection of claims 1, 4, 6, 7, 9, 10, 14–17,
20, 21, and 26–29 under the ground of nonstatutory double patenting as
unpatentable over claims 1–15 of US 9,320,799. See In re Bush, 296 F.2d
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491, 496 (CCPA 1961) (holding that the Board may rely on fewer than all of
the references relied on by the Examiner in an obviousness rationale without
designating it as a new ground of rejection.)
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1, 4, 6, 7,
9, 10, 14–
17, 20, 21,
26–29
103(a) Shin-Etsu, Ramji,
Allaire, Curatolo
1, 4, 6, 7,
9, 10, 14–
17, 20, 21,
26–29
1, 4, 6, 7,
9, 10, 14–
17, 20, 21,
26–29
103(a) Curatolo 1, 4, 6, 7,
9, 10, 14–
17, 20, 21,
26–29
1, 4, 6, 7,
9, 10, 14–
17, 20, 21,
26–29
Nonstatutory
Double Patenting
(US 9320799,
Curatolo)
1, 4, 6, 7,
9, 10, 14–
17, 20, 21,
26–29

Overall
Outcome
1, 4, 6, 7,
9, 10, 14–
17, 20, 21,
26–29

TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED