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`NOTE: This disposition is nonprecedential.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,
`
`

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`Case: 22-1946 Document: 48 Page: 2 Filed: 01/02/2024
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`2
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`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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`Case: 22-1946 Document: 48 Page: 3 Filed: 01/02/2024
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`PURECIRCLE USA INC. v. SWEEGEN, INC.
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`3
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`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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`PURECIRCLE USA INC. v. SWEEGEN, INC.
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`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.
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`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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`PURECIRCLE USA INC. v. SWEEGEN, INC.
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`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.
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`7
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`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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`PURECIRCLE USA INC. v. SWEEGEN, INC.
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`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.
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`9
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`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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`PURECIRCLE USA INC. v. SWEEGEN, INC.
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`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.
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`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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`PURECIRCLE USA INC. v. SWEEGEN, INC.
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`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.
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`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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`PURECIRCLE USA INC. v. SWEEGEN, INC.
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`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
`
`

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`Case: 22-1946 Document: 48 Page: 15 Filed: 01/02/2024
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`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
`
`
`

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`Case: 22-1946 Document: 48 Page: 16 Filed: 01/02/2024
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`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.
`
`