E.I. DUPONT DE NEMOURS & COMPANY, ARCHER DANIELS MIDLAND COMPANY, Appellants
SYNVINA C.V., Appellee
from the United States Patent and Trademark Office, Patent
Trial and Appeal Board in No. IPR2015-01838.
Michael J. Flibbert, Finnegan, Henderson, Farabow, Garrett
& Dunner, LLP, Washington, DC, argued for appellants.
Also represented by Charles Collins-Chase.
M. Richter, Jr., Pepper Hamilton LLP, New York, NY, argued
for appellee. Also represented by Mark Alexander Chapman,
Hunton Andrews Kurth LLP, New York, NY.
Lourie, O'Malley, and Chen, Circuit Judges.
Lourie, Circuit Judge.
du Pont de Nemours and Company and Archer-Daniels-Midland
Company (collectively, "DuPont") appeal from an
inter partes review ("IPR") decision of
the United States Patent and Trademark Office Patent Trial
and Appeal Board (the "Board"). See DuPont v.
Furanix Techs. B.V., No. IPR2015-01838, Paper No. 43,
slip op. (P.T.A.B. Mar. 3, 2017)
("Decision"). The Board held that DuPont
failed to prove by preponderant evidence that claims 1-5 and
7-9 of U.S. Patent 8, 865, 921 ("'921 patent")
would have been obvious at the time of the claimed invention.
We conclude that the Board applied the wrong legal standards
for obviousness, and reverse.
C.V. ("Synvina") owns the '921 patent, directed to a
method of oxidizing 5-hydroxymethylfurfural ("HMF")
or an HMF derivative, such as 5-methylfurfural
("5MF") or 2, 5-dimethylfuran ("DMF"),
under specified reaction conditions to form 2, 5-furan
dicarboxylic acid ("FDCA"). '921 patent
Abstract; id. col. 7 l. 65. Undisput-edly, the
oxidation of HMF and its derivatives to yield FDCA was known
at the time of the claimed invention. The main issue on
appeal is whether the reaction conditions claimed in the
'921 patent-specifically, the choice of temperature,
pressure, catalyst, and solvent-would have been obvious to a
person of ordinary skill at the time of the invention.
and Synvina are competitors in the production of FDCA for
industrial use. FDCA has attracted commercial interest
because of its potential in the "green" chemical
industry. Since FDCA can be produced from sugars using
biological or chemical conversion, the U.S. Department of
Energy has identified FDCA as a potential "building
block" for "high-value bio-based chemicals or
materials." U.S. Department of Energy, Top Value Added
Chemicals from Biomass 1 (2004); see '921 patent
col. 1 ll. 34-36.
'921 patent claims a method of producing FDCA by
oxidizing HMF or an HMF derivative with an oxygen-containing
gas such as air. Claim 1 is illustrative and reads as
1. A method for the preparation of 2, 5-furan di-carboxylic
acid comprising the step of contacting a feed comprising a
compound selected from the group consisting of
5-hydroxymethylfurfural ("HMF"), an ester of
5-(chloromethyl)furfural, 5-methylfuroic acid,
5-(chloromethyl)furoic acid, 2, 5-dimethylfuran and a mixture
of two or more of these compounds with an oxygen-containing
gas, in the presence of an oxidation catalyst comprising
both Co and Mn, and further a source of bromine, at a
temperature between 140° C. and 200° C. at an oxygen
partial pressure of 1 to 10 bar, wherein a solvent or solvent
mixture comprising acetic acid or acetic acid and water
mixtures is present.
'921 patent col. 7 l. 61-col. 8 l. 6 (emphasis added).
Thus, claim 1 recites four relevant reaction conditions: (1)
a temperature between 140°C and 200°C; (2) an oxygen
partial pressure ("PO2") of 1 to 10 bar; (3) a solvent
comprising acetic acid; and (4) a catalyst comprising cobalt
("Co"), manganese ("Mn"), and bromine
specification describes the reaction conditions in further
detail. We begin with temperature. At several points, the
specification refers to the reaction occurring at
temperatures "higher than 140° C." Id.
Abstract, col. 2 ll. 41-42, col. 2 ll. 57-58, col. 5 ll.
18-19, col. 5 l. 39, col. 5 l. 57. When the specification
refers to the temperature range in claim 1, it states that
"[t]he temperature of the reaction mixture is at least
140° C., preferably from 140 and 200° C., most
preferably between 160 and 190° C." Id.
col. 4 ll. 56-58. But "[t]emperatures higher than
180°C. may lead to decarboxylation and to other
degradation products." Id. col. 4 ll. 58-59.
the specification provides the following guidance regarding
The pressure in a commercial oxidation process may vary
within wide ranges. When a diluent is present, and in
particular with acetic acid as diluent, the temperature and
the pressure in such a process are not independent. The
pressure is determined by the solvent (e.g., acetic acid)
pressure at a certain temperature. The pressure of the
reaction mixture is preferably selected such that the solvent
is mainly in the liquid phase.
Id. col. 4 ll. 34-41. Because oxygen functions as
the oxidant in the reaction, its partial pressure is
particularly relevant. "In the case of continuously
feeding and removing the oxidant gas to and from the reactor,
the oxygen partial pressure will suitably be between 1
and 30 bar or more preferably between 1 and 10
bar." Id. col. 4 ll. 51-55 (emphasis
as indicated above, "[t]he most preferred solvent is
acetic acid." Id. col. 4 ll. 17-18. Fourth, the
catalyst is preferably "based on both cobalt and
manganese and suitably containing a source of bromine."
Id. col. 3 ll. 38-40. The catalyst may also contain
"one or more additional metals, in particular
[zirconium] and/or [cerium]." Id. col. 3 ll.
dependent claims recite narrower conditions than those
recited in claim 1. Claims 2-5 each depend from claim 1.
Claim 2 limits the starting material to HMF, esters of HMF,
and a mixture thereof. Id. col. 8 ll. 7-10. Claims 3
and 4 recite a catalyst with an additional metal, such as
zirconium ("Zr") or cerium ("Ce").
Id. col. 8 ll. 11-12, 60-61. And claim 5 recites a
narrower temperature range between 160 and 190°C.
Id. col. 8 ll. 62-63.
conducting the oxidation reaction under the disclosed
reaction conditions, the specification states that the
inventors "surprisingly" achieved high yields of
FDCA, id. col. 2 ll. 39-45, and both Furanix and
Synvina have pointed to these yields as objective evidence of
nonobviousness. The '921 patent reports yields for
several reactions under the claimed conditions. Table 1
summarizes results for oxidizing HMF, an ester of HMF,
5-acetoxymethylfurfural ("AMF"), or a mixture of
the two to produce FDCA. Multiple experiments were conducted
at a temperature of 180°C and a pressure of 20 bars air
in an acetic acid solvent. Id. col. 6 ll. 34-46. The
highest yield of 78.08% was obtained with only HMF as a
reactant, while the lowest was 46.85% using AMF alone.
Id. Table 1.
shows the FDCA yields reported in table 1 for the AMF
oxidation reactions compared to prior art processes conducted
at lower temperatures and a pressure of 30 bars air.
Id. Table 2; id. col. 6 ll. 50-62. FDCA
yields achieved using prior art processes were "lower
than the results obtained at higher temperature."
Id. col. 6 ll. 50- 61.
shows FDCA yields for six experiments when HMF derivatives
5MF or DMF are oxidized with air. The temperature was
180°C, the air pressure was 50 bars, and the solvent was
acetic acid. Id. col. 6 l. 66-col. 7 l. 12. Again,
the concentration of bromine in the catalyst varied across
experiments. Reported FDCA yields for 5MF were 42.62% and
39.94%. Id. Table 3. For DMF, FDCA yields ranged
from 7.19% to 16.17%. Id.
addition to claiming methods of producing FDCA, the '921
patent also claims certain post-production processes. Claim 7
is independent and recites producing FDCA under the
conditions in claim 1, and then "esterify-ing the thus
obtained product." Id. col. 9 ll. 1-14. Claims
8 and 9 depend from claim 7 and recite further details of the
esterification not relevant to this appeal. Id. col.
9 ll. 15-19. The specification recognizes that "[t]he
esterifica-tion of [FDCA] is known." Id. col. 5
ll. 42-48 (citing U.S. Patents 2, 673, 860 and 2, 628, 249);
see also id. col. 5 l. 62- col. 6 l. 2 (citing GB
petitioned for IPR of the '921 patent. The petition
asserted several grounds of obviousness, two of which are
relevant on appeal: (1) claims 1-5 over the '732
alone or in combination with RU '177 and the '318
and (2) claims 7-9 over the '732 publication in view of
Applicants Admitted Prior Art, or additionally
and/or Oae, 
and optionally in view of RU '177 and the '318
Board instituted review of claims 1-5 and 7-9 based on
grounds 1 and 2 above, but did not institute review of the
other claims or grounds. DuPont v. Fu-ranix Techs. B.V.,
No. IPR2015-01838, Paper No. 10, slip op. at 15, 19 (P.T.A.B.
Mar. 9, 2016) ("Institution Decision").
the three references relevant to claims 1-5 disclosed
oxidizing HMF or an HMF derivative to produce FDCA, but did
so under somewhat different conditions. First, the '732
publication disclosed oxidizing HMF to FDCA. It included
"preferred temperatures" of "about 50° to
250°C, most preferentially about 50° to
160°C." J.A. 2360. Like the '921 patent, the
'732 publication indicated that the reaction pressure
"is such to keep the solvent mostly in the liquid
phase." Id. Specifically, the reference
disclosed that an air pressure of 1000 psi "gave good
yields of [FDCA]." J.A. 2368. 1000 psi amounts to a PO2
of approximately 14.5 bars. The disclosed solvent was
"preferably acetic acid," J.A. 2357, and "the
catalyst can be comprised of Co and/or Mn, and Br, and
optionally Zr," J.A. 2358. Reported FDCA yields ranged
from 14% to 58.8%.
RU '177 disclosed oxidizing 5MF to form FDCA. It included
a method where the oxidation reaction "is conducted at
the temperature of 115-140°C and air pressure of 10-50
atm." J.A. 2440. An air pressure of 10- 50 atm roughly
corresponds to a PO2 of 2.1-10.5
'177 also generally recites an "aliphatic carboxylic
acid" as the solvent, and an example in the
specification specifically uses acetic acid. Id. The
catalyst in RU '177 is "a mixture of cobalt acetate
and manganese acetate, as well as bromine-containing
compounds, such as ammonium bromide." Id.
Purportedly, the process "has a number of advantages
compared to prior art: it utilizes readily available and
inexpensive reagents as the initial compound and catalysts;
[and] the method is a one-step process." J.A. 2439. FDCA
yields reportedly ranged from 23-36%.
the '318 publication taught the oxidation of HMF to make
FDCA. The reaction temperature was "from about 50°
C. to about 200° C," with a preferred range of
100-160°C. J.A. 2484, 2486. "A preferred pressure
can typically be in the range of 150-500 psi," J.A.
2486, corresponding to a PO2 range in air of roughly 2.17-
7.24 bars. Unlike the '921 patent and the other
references, the '318 publication taught using water as a
solvent and a platinum catalyst. Under these conditions, the
'318 publication reported yields "as high as
98%." J.A. 2486.
table below summarizes the reaction conditions disclosed in
claim 1 of the '921 patent and in the RU '177,
'732, and '318 references. For simplicity and to
enable comparison between pressure ranges, we restate only
the PO2 ranges in bars under the assumption that air is the
50-250°C, preferably 50-160°C
Co/Mn/Br, optionally Zr
50-200°C, preferably 100-160°C
additional references, Lewkowski and Oae, are relevant to the
FDCA esterification claims 7-9. Consistent with the '921
patent's acknowledgment that esterification of FDCA was
known at the time of the invention, '921 patent col. 5 l.
42, Lewkowski and Oae both disclosed esterifying FDCA.
final written decision, the Board held the instituted claims
not unpatentable as obvious. The Board rejected DuPont's
contention that a burden-shifting framework applied,
reasoning that our decisions in In re Magnum Oil Tools
International, Ltd., 829 F.3d 1364, 1375 (Fed. Cir.
2016), and Dynamic Drinkware, LLC v. National Graphics,
Inc., 800 ...