Case: 22-1946 Document: 48 Page: 1 Filed: 01/02/2024
NOTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
PURECIRCLE USA INC., PURECIRCLE SDN BHD,
Plaintiffs-Appellants
v.
SWEEGEN, INC., PHYTO TECH CORP., DBA BLUE
CALIFORNIA,
Defendants-Appellees
______________________
2022-1946
______________________
Appeal from the United States District Court for the
Central District of California in No. 8:18-cv-01679-JVS-
JDE, Judge James V. Selna.
______________________
Decided: January 2, 2024
______________________
STANLEY JOSEPH PANIKOWSKI, III, DLA Piper US LLP,
San Diego, CA, argued for plaintiffs-appellants. Also rep-
resented by RICHARD T. MULLOY; STUART ERIC POLLACK,
Kilpatrick Townsend & Stockton LLP, New York, NY.
JOHN CHRISTOPHER ROZENDAAL, Sterne Kessler Gold-
stein & Fox PLLC, Washington, DC, argued for defend-
ants-appellees. Also represented by MICHAEL E. JOFFRE,
Case: 22-1946 Document: 48 Page: 2 Filed: 01/02/2024
2 PURECIRCLE USA INC. v. SWEEGEN, INC.
ANNA G. PHILLIPS, SASHA RAO, DENNIES VARUGHESE,
DEIRDRE M. WELLS.
______________________
Before DYK, SCHALL, and STARK, Circuit Judges.
DYK, Circuit Judge.
PureCircle USA Inc. and PureCircle Sdn Bhd (collec-
tively, “PureCircle”), the owners of U.S. Patent Nos.
9,243,273 (“’273 patent”) and 10,485,257 (“’257 patent”),
brought suit for infringement against defendants Swee-
Gen, Inc. and Phyto Tech Corp. d/b/a Blue California (col-
lectively, “SweeGen”). The District Court for the Central
District of California granted summary judgment to de-
fendants, concluding that all claims of the asserted patents
were invalid due to a lack of written description, and that
claims 1–11 and 14 of the ’273 patent and claims 1–5 of the
’257 patent were unpatentable under 35 U.S.C. § 101. We
conclude that claims 1–13 of the ’273 patent and all claims
of the ’257 patent are invalid for lack of written description,
and we also conclude that claim 14 of the ’273 patent is un-
patentable under § 101. We affirm.
BACKGROUND
Steviol glycosides are naturally occurring compounds
found in stevia plants that can be used as non-caloric
sweeteners. One particular steviol glycoside, known as Re-
baudioside X (“Reb X”) or Rebaudioside M (“Reb M”), was
identified in trace amounts in stevia plants. Because only
small amounts of Reb X naturally occur in stevia plants, it
would be expensive and inefficient to extract Reb X from
the plants. PureCircle’s two patents at issue in this case,
U.S. Patent Nos. 9,243,273 and 10,485,257, claim a method
of producing Reb X using enzymes called UDP-
glucosyltransferases (“UGTs”), the same enzymes used in
plants to synthesize the compound. Claims 1 and 14 of the
’273 patent are representative, and provide:
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PURECIRCLE USA INC. v. SWEEGEN, INC. 3
1. A method for making Rebaudioside X comprising
a step of converting Rebaudioside D to Rebaudi-
oside X using a UDP-glucosyltransferase, wherein
the conversion of Rebaudioside D to Rebaudioside
X is at least about 50% complete.
14. The method of claim 1, wherein the UDP-
glucosyltransferase comprises UGT76G1.
PureCircle filed suit in district court against defend-
ants alleging infringement of the ’273 and ’257 patents.
The parties stipulated to the claim construction of UGTs as
“[a] type of enzyme that is capable of transferring a glucose
unit from a uridine diphosphate glucose molecule to a ste-
viol glycoside molecule.” J.A. 5159–60. The district court
held that based on the parties’ stipulation, the term was
functionally defined. SweeGen moved for summary judg-
ment of invalidity for lack of written description under 35
U.S.C. § 112 and subject matter ineligibility under 35
U.S.C. § 101. The district court partially granted Swee-
Gen’s motion, finding all claims of the ’273 and ’257 patents
invalid due to a lack of written description and claims 1–
11 and 14 of the ’273 patent and claims 1–5 of the ’257 pa-
tent unpatentable under § 101. PureCircle appeals.
We have jurisdiction under 28 U.S.C. § 1295(a)(1).
DISCUSSION
We review the grant of summary judgment de novo.
E.g., Monzon v. City of Murrieta, 978 F.3d 1150, 1155 (9th
Cir. 2020). “A grant of summary judgment is ‘proper only
where there is no genuine issue of any material fact or
where viewing the evidence and the inferences which may
be drawn therefrom in the light most favorable to the ad-
verse party, the movant is clearly entitled to prevail as a
matter of law.’” Clarkson v. Alaska Airlines, Inc., 59 F.4th
424, 432 (9th Cir. 2023) (quoting Sandvik v. Alaska Packers
Ass’n, 609 F.2d 969, 974 (9th Cir. 1979)).
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4 PURECIRCLE USA INC. v. SWEEGEN, INC.
I
Section 112 requires that a patent’s “specification shall
contain a written description of the invention.” 35 U.S.C.
§ 112(a). To satisfy the written description requirement,
the specification must “clearly allow persons of ordinary
skill in the art to recognize that [the inventor] invented
what is claimed.” Ariad Pharms., Inc. v. Eli Lilly & Co.,
598 F.3d 1336, 1351 (Fed. Cir. 2010) (en banc) (alteration
in original) (quoting Vas-Cath Inc. v. Mahurkar, 935 F.2d
1555, 1563 (Fed. Cir. 1991)). That is it must “reasonably
convey[] to those skilled in the art that the inventor had
possession of the claimed subject matter as of the filing
date.” Id. “What is required to meet the written descrip-
tion requirement ‘varies with the nature and scope of the
invention at issue, and with the scientific and technologic
knowledge already in existence.’” Juno Therapeutics, Inc.
v. Kite Pharma, Inc., 10 F.4th 1330, 1335 (Fed. Cir. 2021)
(quoting Capon v. Eshhar, 418 F.3d 1349, 1357 (Fed. Cir.
2005)). For genus claims the specification must “provide
sufficient ‘blaze marks’ to guide a reader through the forest
of disclosed possibilities toward the claimed compound.”
Novozymes A/S v. DuPont Nutrition Biosciences APS, 723
F.3d 1336, 1346 (Fed. Cir. 2013) (quoting In re Ruschig, 379
F.2d 990, 995 (C.C.P.A. 1967)).
In the context of a genus claim, written description “re-
quires the disclosure of either a representative number of
species falling within the scope of the genus or structural
features common to the members of the genus so that one
of skill in the art can ‘visualize or recognize’ the members
of the genus.” Ariad, 598 F.3d at 1350 (quoting Regents of
the Univ. of California v. Eli Lilly & Co., 119 F.3d 1559,
1568–69 (Fed. Cir. 1997)). The claims of the ’273 and ’257
patents are properly construed as genus claims using func-
tional language, as the district court concluded. The pa-
tents claim a genus of UGT enzymes, and PureCircle and
SweeGen stipulated to a construction of UGTs that defines
the enzyme by what it does, i.e., its function – transferring
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PURECIRCLE USA INC. v. SWEEGEN, INC. 5
a glucose unit from a uridine diphosphate glucose molecule
to a steviol glycoside molecule.
SweeGen argues that the ’273 and ’257 patents are in-
valid because they do not disclose a representative number
of species nor common structural features of the claimed
UGT genus to identify which enzymes would function to
convert Reb D to Reb X at a 50% completion level or
higher. 1 SweeGen contends that the claim language covers
at least one trillion enzymes that could potentially perform
that function. 2 SweeGen’s expert reached this number by
assuming UGT enzymes consisted of 100 amino acids,
there were 733 known UGT sequences as of 2012, five
amino acids could be substituted to make mutations, and
each substitution could consist of 19 different amino acids.
SweeGen further argues that while the genus claimed is
enormous, only one enzyme (UGT76G1) was given as a rep-
resentative species. There is no dispute that the common
specification of the ’273 and ’257 patents identifies only one
UGT that it says can make Reb X. Because only one en-
zyme of the potentially vast class of UGTs is disclosed,
SweeGen argues, the patent does not disclose a representa-
tive number of species. SweeGen also argues that there
was no known common structure of UGTs as of the patent’s
priority date.
1 Claim 11 recites “[t]he method of claim 1, wherein
the conversion is at least about 95% complete.” ’273 patent,
col. 36, ll. 9–10.
2 SweeGen contends this is an underestimate be-
cause the claims also cover fusion enzymes. Fusion en-
zymes are two or more individual enzyme segments linked
together to form a single enzyme. In this case, the parties
dispute whether any enzyme fused with UGT76G1 would
count as separate enzymes for purposes of written descrip-
tion. For the purposes of this opinion, we assume they are
not.
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6 PURECIRCLE USA INC. v. SWEEGEN, INC.
PureCircle contends that the potential trillions of en-
zymes claimed by SweeGen can drastically be reduced.
There were only five known enzymes that had been shown
to be capable of steviol glycoside synthesis, i.e., enzymes
that come within the scope of the claims. 3 While each of
these enzymes would have a large number of mutations,
PureCircle argues that the mutations capable of the re-
quired synthesis can be determined with reasonable cer-
tainty through homology modeling. Homology modeling
consists of entering the amino acid sequence of an enzyme
into the modeling program, then (based on the amino acid
sequence) the computer predicts how the enzyme will fold,
ultimately producing a 3-D model of the enzyme. Looking
at the model of a working enzyme, PureCircle argues, a
person of ordinary skill in the art (POSA) could find the
active site where that enzyme converts Reb D to Reb X, and
then compare the structure of that active site to the struc-
ture of mutant enzymes. If the structure of the active sites
is the same, then the mutant enzyme is likely capable of
the conversion of Reb D into Reb X.
Using such modeling, PureCircle provided evidence
that there were only 1,800 possible mutations for each of
the five known enzymes, or a total of 9,000 possible UGTs.
While these mutants would have to be tested to ascertain
3 A total of twelve enzymes were known to belong to
the family named UGTs. Only one of the five enzymes,
UGT76G1, was known to produce Reb X. While the patent
cites one other UGT enzyme, UGT91D2, and contains a nu-
cleic acid sequence of that enzyme, the patents do not indi-
cate that UGT91D2 can convert Reb D to Reb X. See J.A.
92-93 at col. 2, l. 66–col. 3, l. 3. By contrast, the patents
explicitly state that UGT76G1 is a UGT “capable of adding
at least one glucose unit to rebaudioside D to form rebau-
dioside X.” See J.A. 93 at col. 3, ll.4–6.
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PURECIRCLE USA INC. v. SWEEGEN, INC. 7
if they could actually convert Reb D to Reb X, PureCircle
argues that such testing was routine.
II
PureCircle argues that disclosure of a single enzyme
can satisfy the written description requirement, and that
under our cases, disclosure of a single compound (here, a
single enzyme) may be representative of the genus. See,
e.g., Invitrogen Corp. v. Clontech Labs., Inc., 429 F.3d 1052,
1073 (Fed. Cir. 2005); Bilstad v. Wakalopulos, 386 F.3d
1116, 1124 (Fed. Cir. 2004) (“[T]his court has continued to
apply the rule that disclosure of a species may be sufficient
written description support for a later claimed genus in-
cluding that species.”). While a single example can provide
written description support for a genus, that is not the case
unless the specification provides the required “blaze
marks.” 4
PureCircle contends that the single disclosed enzyme
here is representative of the genus because the structure of
its active site was common to all claimed UGTs. In other
words, PureCircle contends that the compound here (the
UGT76G1 enzyme) discloses common structural features
sufficient to define the genus.
4 See, e.g., LizardTech, Inc. v. Earth Res. Mapping,
Inc., 424 F.3d 1336, 1346 (“Thus, a patentee cannot always
satisfy the requirements of section 112, in supporting ex-
pansive claim language, merely by clearly describing one
embodiment of the thing claimed.”); Juno, 10 F.4th at 1337
(“The disclosure of one scFv that binds to CD19 and one
scFv that binds to a PSMA antigen on prostate cancer cells
in the manner provided in this patent does not provide in-
formation sufficient to establish that a skilled artisan
would understand how to identify the species of scFvs ca-
pable of binding to the limitless number of targets as the
claims require.”).
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8 PURECIRCLE USA INC. v. SWEEGEN, INC.
Construing the evidence in the light most favorable to
PureCircle, it is clear that any structural features common
to the members of the genus were not sufficiently disclosed
so as to allow one of skill in the art to visualize or recognize
the members of the genus. First, there is no mention in the
claims or specification of homology modeling for determin-
ing common structure. PureCircle argues that homology
modeling does not need to be disclosed because it was al-
ready a known technique to a POSA. 5 Even if homology
modeling did not need to be disclosed in the specification,
even for the five known enzymes, extensive trial and error
testing after homology modeling (which by PureCircle’s ad-
mission would result in 9,000 compounds) would be re-
quired to identify potential active candidates. In general
the need for extensive trial and error testing argues
against a finding of adequate written description. Our de-
cision in Novozymes is instructive. There, the patentee ar-
gued that “one of ordinary skill in the art . . . would have
known how to test every possible variant at that position
and thus would have found the claimed variants as a mat-
ter of course.” 723 F.3d at 1350. We explained that “[t]he
question before us is not whether one of ordinary skill in
the art presented with the [relevant] application would
have been enabled to take those final steps, but whether
the [relevant] application ‘discloses the [variants] to him,
specifically, as something appellants actually invented.’”
Id. (second alteration in original) (quoting Ruschig, 379
F.2d at 995). 6
5 Compare Capon, 418 F.3d at 1358 (“When the prior
art includes the nucleotide information, precedent does not
set a per se rule that the information must be determined
afresh.”) (emphasis in original).
6 See also In re Alonso, 545 F.3d 1015, 1020 (Fed. Cir.
2008) (“[I]t is not enough to describe[] the procedure for
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PURECIRCLE USA INC. v. SWEEGEN, INC. 9
Second, there are potentially additional unknown en-
zymes that could achieve the conversion to produce Reb X,
as PureCircle admits. 7 These additional enzymes would
not necessarily share common structure with UGT76G1.
The specification contains the amino acid sequence of
UGT76G1, but it does not identify which part of the amino
acid sequence is necessary for the conversion function of
the enzyme. PureCircle repeatedly points to testimony by
its expert, Dr. Bollinger, that UGTs “all had common struc-
tural features,” J.A. 5570 ¶ 286, though inconsistently stat-
ing that “no experimentally determined structure of a
UDP-glucosyltransferase was known in 2012.” J.A. 5571
¶ 290. However, Dr. Bollinger did not relate any common
structure to the function of the enzyme, other than to men-
tion homology modeling. If other enzymes do exist, Pure-
Circle admits that homology modeling cannot be used to
making a human-human hybridoma from neurofibrosar-
coma, and teach how to determine whether a given anti-
body, specific to a patient’s neurofibrosarcoma, will
function in the claimed method.”); Univ. of Rochester v.
G.D. Searle & Co., 358 F.3d 916, 925 (Fed. Cir. 2004)
(“[O]ne of skill in the art would [not], from reading the pa-
tent, understand what compound or compounds—which, as
the patent makes clear, are necessary to practice the
claimed method—would be suitable, nor would one know
how to find such a compound except through trial and er-
ror.” (citation omitted)).
7 THE COURT: “And then, there is the possibility
that in the future that additional enzymes would be iden-
tified which achieve the conversion and the claims would
cover those new enzymes as well, right?”
COUNSEL FOR PURECIRCLE: “Correct your
Honor.”
Oral Argument at 1:17–1:31.
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10 PURECIRCLE USA INC. v. SWEEGEN, INC.
identify those unknown enzymes. 8 Homology modeling
alone cannot determine what structural features are com-
mon to enzymes capable of producing Reb X. It can only
create 3-D structures of enzymes with known amino acid
sequences which can be used by a POSA to determine com-
mon structures of mutants of a known enzyme, not the
structures of other enzymes.
As to other enzymes that could perform the function,
PureCircle offered no evidence as to whether it was likely
or unlikely that those additional enzymes exist or what
their structure might be. In our prior cases where there
has been a large genus, encompassing both known and un-
known compounds, we have held that in order for the dis-
closed species to be representative of the genus, it has to
provide blaze marks that would allow a POSA to identify
other members of the genus. No such blaze marks are pre-
sent here.
In Juno, the patent claimed a large genus of “any scFv
for binding any target.” Juno, 10 F.4th at 1336. We ex-
plained that “[t]o satisfy written description, however, the
inventors needed to convey that they possessed the claimed
invention, which encompasses all scFvs, known and un-
known, as part of the claimed [chimeric antigen receptor]
CAR that bind to a selected target.” Id. at 1338. We held
written description was not satisfied because “the specifi-
cation provides no means of distinguishing which scFvs
will bind to which targets,” id., and the patent “contains no
details about these scFv species beyond the alphanumeric
8 THE COURT: “But as I understand it, homology
modeling would not help you identify other enzymes, not
mutations, but other enzymes besides the four or five that
perform the conversion, correct?”
COUNSEL FOR PURECIRCLE: “Correct your
Honor.”
Oral Argument at 15:26–15:41.
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PURECIRCLE USA INC. v. SWEEGEN, INC. 11
designations J591 and SJ25C1 for a skilled artisan to de-
termine how or whether they are representative of the en-
tire claimed genus,” id. at 1336. Apart from the one specific
example, here, as in Ariad, 598 F.3d at 1353, “[s]uch claims
merely recite a description of the problem to be solved
while claiming all solutions to it and . . . cover any com-
pound later actually invented and determined to fall within
the claim’s functional boundaries—leaving it to the phar-
maceutical industry to complete an unfinished invention.”
In short, the one enzyme disclosed in the patents here
has not been shown to be typical of the entire genus of
UGTs claimed. 9 Under such circumstances, there is no ad-
equate written description. In AbbVie, we found a lack of
written description because “AbbVie’s patents only de-
scribe one type of structurally similar antibodies and []
those antibodies are not representative of the full variety
or scope of the genus.” AbbVie Deutschland GmbH & Co.,
KG v. Janssen Biotech, Inc., 759 F.3d 1285, 1300 (Fed. Cir.
2014). Likewise, in Idenix, we held that because the pa-
tents provided “lists or examples of supposedly effective nu-
cleosides, but d[id] not explain what makes them effective,
or why . . . a POSA is deprived of any meaningful guidance
into what compounds beyond the examples and formulas,
if any, would provide the same result.” Idenix Pharms.
9 PureCircle points to a decision by the United States
Patent and Trademark Office (“PTO”) denying post-grant
review because it found that it was more likely than not
that written description was satisfied. A decision from the
PTO “may be persuasive but it is not binding precedent on
this court.” Noelle v. Lederman, 355 F.3d 1343, 1350 (Fed.
Cir. 2004). Here, the PTO misunderstood the limits of ho-
mology modeling and did not take into account that un-
known enzymes could convert Reb D to Reb X.
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12 PURECIRCLE USA INC. v. SWEEGEN, INC.
LLC v. Gilead Scis. Inc., 941 F.3d 1149, 1164 (Fed. Cir.
2019). 10
PureCircle finally contends that the original claims
doctrine provides sufficient written description support.
However, the claims of the original application—Applica-
tion No. PCT/US2013/030439—do not help PureCircle be-
cause they do not provide any additional information about
common structural features or representative species of
the genus. “If a purported description of an invention does
10 PureCircle relies on Ajinomoto Co. v. Int’l Trade
Comm’n, 932 F.3d 1342, 1360 (Fed. Cir. 2019) for the prop-
osition that the knowledge of a POSA should be taken into
account. Ajinomoto is inapposite. In Ajinomoto, the patent
claimed a “more potent promoter” but disclosed four exam-
ples of promoters and cited an article that “provide[d] data
about the relative strength of fourteen promoters and de-
scribe[d] a general methodology for determining promoter
strength.” 932 F.3d at 1347, 1359. Further, there was a
“well-known link between consensus sequence and pro-
moter strength” as “promoters having fewer departures
from a ‘consensus sequence’ in a promoter are generally
stronger” and “the genus of more potent promoters was al-
ready well explored in the relevant art.” Id. at 1359–60.
Even though there was some evidence that “deviations
from [the consensus] sequence d[id] not always decrease
promoter strength,” this Court held that “[a]dequate writ-
ten description does not require a perfect correspondence
between the members of the genus and the asserted com-
mon structural feature.” Id. at 1360. Thus, Ajinomoto
stands for the idea that where there are structural features
common to a genus, the structure-function correlation does
not need to be perfect and some testing—appropriate to the
knowledge of a POSA—is allowed, not that an unknown
structure-function correlation along with extensive testing
can satisfy written description.
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PURECIRCLE USA INC. v. SWEEGEN, INC. 13
not meet the requirements of the statute, the fact that it
appears as an original claim or in the specification does not
save it. A claim does not become more descriptive by its
repetition, or its longevity.” Enzo Biochem, Inc. v. Gen-
Probe Inc., 323 F.3d 956, 968–69 (Fed. Cir. 2002). Thus,
the original claims doctrine does not provide adequate
written description support.
Under these circumstances, we hold that claims 1-13 of
the ’273 patent and claims 1-7 of the ’257 patent are invalid
for lack of written description.
III
PureCircle contends that even if the other claims lack
written description support, claim 14 of the ’273 patent sat-
isfies the written description requirement because, unlike
the other claims, it names a specific enzyme, UGT76G1.
Thus, PureCircle argues, through homology modeling only
1,800 possible mutations would be covered and testing that
small group of enzymes for functionality does not run afoul
of the written description requirement. We need not decide
that issue, because we conclude that, as the district court
held, claim 14 is unpatentable under § 101.
Section 101 of Title 35 provides that “any new and use-
ful process, machine, manufacture, or composition of mat-
ter, or any new and useful improvement thereof” is patent-
eligible subject matter. 35 U.S.C. § 101. However, the Su-
preme Court has recognized an important exception, and
“[l]aws of nature, natural phenomena, and abstract ideas
are not patentable.” Ass’n for Molecular Pathology v. Myr-
iad Genetics, Inc., 569 U.S. 576, 589 (2013) (quoting Mayo
Collaborative Servs. v. Prometheus Lab’ys, Inc., 566 U.S.
66, 70 (2012)).
The proper § 101 analysis was described by the Su-
preme Court in Alice and Mayo. At step one of the Al-
ice/Mayo test, we determine whether the claims are
directed to a law of nature, natural phenomenon, or an
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14 PURECIRCLE USA INC. v. SWEEGEN, INC.
abstract idea. Alice Corp. Pty. v. CLS Bank Int’l, 573 U.S.
208, 217 (2014) (citing Mayo, 566 U.S. at 77). If the claims
are so directed, we then at step two determine if the claims
embody an “inventive concept,” meaning “an element or
combination of elements that is ‘sufficient to ensure that
the patent in practice amounts to significantly more than
a patent upon the [ineligible concept] itself.’” Id. at 217–18
(alteration in original) (quoting Mayo, 566 U.S. at 72–73).
To the extent that claim 14 claims a “method for mak-
ing Rebaudioside X comprising a step of converting Rebau-
dioside D to Rebaudioside X using a UDP-
glucosyltransferase,” it claims a natural phenomenon. The
enzyme in claim 14, UGT76G1, is naturally found in stevia
plants and naturally converts Reb D to Reb X. If that were
the extent of claim 14, it would clearly claim an unpatent-
able natural phenomenon. As the district court noted
“there is no dispute that the conversion of steviol glycosides
and Reb D to Reb [X] using UGT enzymes is a natural pro-
cess.” J.A. 10.
PureCircle argues that the outcome should be different
because in nature only small amounts of Reb X are pro-
duced, whereas claim 1 (from which claim 14 depends) pro-
vides “conversion of Rebaudioside D to Rebaudioside X is
at least about 50% complete.” ’273 patent, col. 35, ll. 4–5.
PureCircle contends that because the conversion of Reb D
to Reb X would never reach 50% completion in nature,
claim 14 is not directed to a natural phenomenon. The
problem with PureCircle’s argument is that the 50% com-
pletion is itself an abstract idea.
To be eligible under § 101, an invention must have the
“specificity required to transform a claim from one claiming
only a result to one claiming a way of achieving it.” SAP
Am., Inc. v. InvestPic, LLC, 898 F.3d 1161, 1167 (Fed Cir.
2018). “[I]n the context of claims to results, we have ex-
plained that claims that ‘simply demand[] the production
of a desired result . . . without any limitation on how to
Case: 22-1946 Document: 48 Page: 15 Filed: 01/02/2024
PURECIRCLE USA INC. v. SWEEGEN, INC. 15
produce that result’ are directed to an abstract idea.” In re
Killian, 45 F.4th 1373, 1382 (Fed. Cir. 2022) (quoting In-
terval Licensing LLC v. AOL, Inc., 896 F.3d 1335, 1345
(Fed. Cir. 2018)); see also Am. Axle & Mfg., Inc. v. Neapco
Holdings LLC, 967 F.3d 1285, 1292 (Fed. Cir. 2020) (“[T]o
avoid ineligibility, a claim must ‘ha[ve] the specificity re-
quired to transform [the] claim from one claiming only a
result to one claiming a way of achieving it.’”). As the dis-
trict court explained, claim 14 of the ’273 patent “d[id] not
specify how to achieve a particular purity or conversion
percentage; rather, [it] only recite[s] the resulting percent-
ages.” J.A. 12. Claim 14 simply states a result, conversion
of Reb D to Reb X wherein the conversion is at least about
50% complete. The claim does not provide any steps or give
guidance as to how to achieve a 50% conversion other than
the direction to use a natural enzyme. Claim 14 is directed
to subject matter that is a natural phenomenon or abstract
idea at step 1 of Alice/Mayo. 11
11 PureCircle points to Natural Alternatives, where
the patent claimed a “method of increasing anaerobic work-
ing capacity in a human subject” through “elevat[ing] beta-
alanine above natural levels to cause an increase in the
synthesis of beta-alanylhistidine dipeptide in the tissue.”
918 F.3d 1338, 1343–44 (Fed. Cir. 2019) (citation omitted).
While the claims in Natural Alternatives similarly claimed
a compound which existed in nature in quantities higher
than natural levels, we explained that the method of appli-
cation involved the method of affirmatively treating pa-
tients with quantities that did not exist in nature, thereby
altering an individual’s natural state. Id. at 1344; see also
id. at 1346 (holding that the “treatment claims . . . cover
using a natural product in unnatural quantities to alter a
patient’s natural state, to treat a patient with specific dos-
ages outlined in the patents”). Claim 14, by contrast, is not
Case: 22-1946 Document: 48 Page: 16 Filed: 01/02/2024
16 PURECIRCLE USA INC. v. SWEEGEN, INC.
PureCircle made no step two Alice/Mayo arguments be-
fore us or the district court. Claim 14 is therefore invalid
as directed to unpatentable subject matter.
CONCLUSION
We affirm the district court’s grant of summary judg-
ment that claims 1–13 of the ’273 patent and claims 1–7 of
the ’257 patent are invalid for lack of written description,
and that claim 14 of the ’273 patent is unpatentable under
35 U.S.C. § 101.
AFFIRMED
a treatment claim. Thus, reliance on Natural Alternatives
is misplaced.