Novartis Pharmaceuticals v. Accord Healthcare Inc. ( 2022 )


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  • Case: 21-1070   Document: 41   Page: 1   Filed: 01/03/2022
    United States Court of Appeals
    for the Federal Circuit
    ______________________
    NOVARTIS PHARMACEUTICALS CORPORATION,
    Plaintiff-Appellee
    v.
    ACCORD HEALTHCARE, INC., AUROBINDO
    PHARMA LTD., AUROBINDO PHARMA USA, INC.,
    DR. REDDY’S LABORATORIES, INC., DR. REDDY’S
    LABORATORIES, LTD., EMCURE
    PHARMACEUTICALS LTD., HERITAGE
    PHARMACEUTICALS INC., GLENMARK
    PHARMACEUTICALS INC., USA, GLENMARK
    PHARMACEUTICALS LIMITED, HETERO USA,
    INC., HETERO LABS LIMITED UNIT-V, HETERO
    LABS LIMITED, MYLAN PHARMACEUTICALS,
    INC., PRINSTON PHARMACEUTICAL INC.,
    STRIDES GLOBAL PHARMA PRIVATE LIMITED,
    STRIDES PHARMA, INC., TORRENT PHARMA
    INC., TORRENT PHARMACEUTICALS LTD.,
    ZYDUS PHARMACEUTICALS (USA) INC., CADILA
    HEALTHCARE LTD., APOTEX INC., APOTEX
    CORP., SUN PHARMACEUTICAL INDUSTRIES,
    LTD., SUN PHARMACEUTICAL INDUSTRIES INC.,
    SUN PHARMA GLOBAL FZE,
    Defendants
    HEC PHARM CO., LTD., HEC PHARM USA INC.,
    Defendants-Appellants
    ______________________
    2021-1070
    ______________________
    Case: 21-1070      Document: 41    Page: 2    Filed: 01/03/2022
    2      NOVARTIS PHARMACEUTICALS   v. ACCORD HEALTHCARE INC.
    Appeal from the United States District Court for the
    District of Delaware in No. 1:18-cv-01043-KAJ, Circuit
    Judge Kent A. Jordan.
    ______________________
    Decided: January 3, 2021
    ______________________
    JANE M. LOVE, Gibson, Dunn & Crutcher LLP, New
    York, NY, argued for plaintiff-appellee. Also represented
    by PAUL E. TORCHIA, ROBERT TRENCHARD.
    PAUL SKIERMONT, Skiermont Derby LLP, Dallas, TX,
    argued for defendants-appellants. Also represented by
    SARAH ELIZABETH SPIRES; MIEKE K. MALMBERG, Los Ange-
    les, CA.
    ______________________
    Before MOORE, Chief Judge, LINN and O’MALLEY, Circuit
    Judges.
    Opinion for the court filed by Circuit Judge O’MALLEY.
    Dissenting opinion filed by Chief Judge MOORE
    O’MALLEY, Circuit Judge.
    HEC Pharm Co., Ltd. and HEC Pharm USA Inc. (col-
    lectively, “HEC”) appeal from a district court bench trial in
    which the court found that a patent assigned to Novartis
    Pharmaceuticals Corp. (“Novartis”), U.S. Patent
    No. 9,187,405 (“the ’405 patent”), is not invalid and that
    HEC’s Abbreviated New Drug Application (“ANDA”) in-
    fringes. HEC argues that the district court erred in finding
    that the ’405 claims do not fail the written description re-
    quirement of 35 U.S.C. § 112(a). Because we do not discern
    any clear error in the district court’s decision, we affirm.
    Case: 21-1070     Document: 41     Page: 3    Filed: 01/03/2022
    NOVARTIS PHARMACEUTICALS    v. ACCORD HEALTHCARE INC.       3
    I.     BACKGROUND
    Novartis markets a 0.5 mg daily dose of fingolimod hy-
    drochloride under the brand name Gilenya. The medica-
    tion is used to treat relapsing remitting multiple sclerosis
    (“RRMS”), a form of multiple sclerosis (“MS”). MS is a de-
    bilitating immune-mediated demyelinating disease in
    which the immune system attacks the myelin coating the
    nerves in the central nervous system. Most MS patients
    initially present as RRMS patients, but many eventually
    develop a secondary progressive form of MS, causing them
    to experience growing disability. There is currently no cure
    for MS. The disease is managed by reducing or preventing
    relapses and thereby slowing disability.
    HEC filed an ANDA seeking approval to market a ge-
    neric version of Gilenya. Novartis sued, alleging that
    HEC’s ANDA infringes all claims of the ’405 patent. 1
    A. The ’405 Patent
    The ’405 patent claims methods to treat RRMS with
    fingolimod (also known as FTY720 and 2-amino-2-[2-(4-oc-
    tylphenyl)ethyl]propane-1,3-diol in the ’405 patent) or a
    fingolimod salt, such as fingolimod hydrochloride (also
    known as Compound A in the ’405 patent), at a daily dosage
    of 0.5 mg without an immediately preceding loading dose.
    ’405 patent col. 12 ll. 49–55.
    A loading dose is a higher than daily dose “usually
    given ‘as the first dose.’” J.A. 27 (¶ 63) (quoting J.A. 23125
    (Tr. 547:12–18) and citing J.A. 23344 (Tr. 766:4–6)). Both
    parties’ experts agreed with this definition. J.A. 23125
    (547:12–18) (HEC’s expert, Dr. Hoffman, testifying that “a
    1    Novartis sued several other defendants who had
    also filed ANDA applications. The cases as to those other
    defendants all settled or were stayed prior to trial, which
    proceeded only as to HEC.
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    4    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.
    loading dose is a higher-than-therapeutic level dose, usu-
    ally given . . . as the first dose in order to get therapeutic
    levels up quickly . . . and it’s usually for more acute situa-
    tions”); J.A. 23344 (Tr. 766:4–6) (Novartis’s expert, Dr.
    Steinman, agreeing that “a loading dose is a higher-than-
    daily dose”). It is undisputed that loading doses were well-
    known in the medical field generally and in the prior art.
    And the experts in this case agree that loading doses are
    used for some medicaments used in connection with MS.
    The ’405 patent has six claims. Claim 1 of the ’405 pa-
    tent recites:
    A method for reducing or preventing or alleviating
    relapses in Relapsing-Remitting multiple sclerosis
    in a subject in need thereof, comprising orally ad-
    ministering to said subject 2-amino-2-[2-(4-oc-
    tylphenyl)ethyl]propane-1,3-diol, in free form or in
    a pharmaceutically acceptable salt form, at a daily
    dosage of 0.5 mg, absent an immediately preceding
    loading dose regimen.
    Claims 3 and 5 are similar but are directed to a
    “method of treating” RRMS and a “method of slowing pro-
    gression of” RRMS, respectively, rather than a “method for
    reducing or preventing or alleviating relapses in” RRMS.
    Id. col. 12 ll. 59–64, col. 13 ll. 1–6. Claims 2, 4, and 6 are
    dependent claims that limit the methods of claims 1, 3, and
    5, respectively, to administration of 2-amino-2-[2-(4-oc-
    tylphenyl)ethyl]propane-1,3-diol hydrochloride, i.e., fin-
    golimod hydrochloride. Id. col. 12 ll. 56–58, col. 12 ll.
    65–67, col. 13 ll. 7–9.
    The ’405 patent was filed on April 21, 2014. It claims
    priority to a British patent application that was filed on
    June 27, 2006. The parties, for the most part, focus their
    discussion on the specification of the ’405 patent, despite
    HEC’s argument that the inventors did not possess the in-
    vention as of the 2006 priority date. HEC’s argument that
    the 2006 application does not contain adequate written
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    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.       5
    description of the ’405 claims requires reference to the 2006
    application itself. Thus, we find it necessary to look to the
    specification of the 2006 priority application, despite the
    parties’ failure to fully explain the contents of that applica-
    tion. Although the specifications are different from each
    other, they are, in all aspects relevant to this appeal, sub-
    stantively similar.
    The specifications of the ’405 patent and the 2006 pri-
    ority application both describe the use of a class of S1P re-
    ceptor modulators, including fingolimod, to treat or prevent
    “neo-angiogenesis associated with a demyelinating disease,
    e.g. multiple sclerosis.” ’405 patent col. 1 ll. 5–8; J.A.
    23751. The specifications each identify fingolimod hydro-
    chloride (Compound A) as a particularly preferred com-
    pound within the class of S1P receptor modulators. ’405
    patent col. 8 ll. 17–30; J.A. 23759–60.
    Both specifications describe the results of an Experi-
    mental Autoimmune Encephalomyelitis (“EAE”) experi-
    ment. ’405 patent col. 10 ll. 32–col. 11 ll. 2; J.A. 23762–63.
    In the EAE experiment, a disease that mimics RRMS was
    induced in Lewis rats. 2 The rats suffered acute disease
    within 11 days after immunization, with almost complete
    remission around day 16 and relapse around day 26. The
    specifications report that an S1P receptor modulator, e.g.,
    Compound A (fingolimod hydrochloride) “significantly
    blocks disease-associated neo-angiogenesis when adminis-
    tered to the animals at a dose of from 0.1 to 20 mg/kg p.o.” 3
    ’405 patent col. 10 ll. 61–64; J.A. 23763. They further re-
    port that disease relapse was completely inhibited in rats
    to which Compound A was “administered daily at a dose of
    2   Lewis rats are inbred laboratory rats used to study
    disease.          Inbred      Rats,     CHARLES       RIVER,
    https://www.criver.com/sites/default/files/resources/Inbre-
    dRatsDatasheet.pdf (last visited November 5, 2021).
    3   P.o. indicates oral administration.
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    6       NOVARTIS PHARMACEUTICALS   v. ACCORD HEALTHCARE INC.
    0.3 mg/kg” or “administered p.o. at 0.3 mg/kg every 2nd or
    3rd day or once a week.” ’405 patent col. 10 ll. 64–col. 11 ll.
    3; J.A. 23763.
    Both specifications then describe a prophetic human
    clinical trial (“Prophetic Trial”). 4 ’405 patent col. 11 ll.
    3–38; J.A. 23763–64. The Prophetic Trial describes a trial
    in which RRMS patients would receive 0.5, 1.25, or 2.5 mg
    of an S1P receptor modulator, e.g., Compound A (fin-
    golimod hydrochloride), per day for two to six months. ’405
    patent col. 11 ll. 8–14; J.A. 23763. The specifications do not
    mention a loading dose associated with the Prophetic Trial.
    ’405 patent col. 11 ll. 8–14; J.A. 23763.
    Both specifications then describe a wide range of poten-
    tial dosages, which “will vary depending upon, for example,
    the compound used, the host, the mode of administration
    and the severity of the condition to be treated.” ’405 patent
    col. 11 ll. 20–24; J.A. 23764. Those potential dosages in-
    clude a “preferred daily dosage range [of] about from 0.1 to
    100 mg” and “a dose of 0.5 to 30 mg [of Compound A] every
    other day or once a week.” ’405 patent col. 11 ll. 24–38; J.A.
    23764.
    B. The District Court Proceedings
    After a four-day bench trial, the district court found
    that HEC’s ANDA product would infringe claims 1–6 of the
    ’405 patent. The court also found that HEC had not shown
    that the ’405 patent is invalid for (1) insufficient written
    description for the no-loading-dose limitation and for the
    4    Prophetic trials explain how a drug would be ad-
    ministered and how a patient given that drug should be
    monitored in a clinical trial. Prophetic trials are not clini-
    cal trials that are performed; they are merely described on
    paper. Prophetic trials are sometimes used in patent ap-
    plications because clinical trials are expensive and time
    consuming.
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    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.       7
    claimed 0.5 mg daily dose or (2) anticipation. HEC appeals
    the district court’s findings as to written description for the
    0.5 mg daily dose and no-loading-dose limitations.
    With respect to the written description for the claimed
    0.5 mg daily dose, the district court found that a skilled ar-
    tisan would understand that the inventors possessed a 0.5
    mg daily dose based on one of the successful doses in the
    EAE experiment results, 0.3 mg/kg weekly. The court cred-
    ited the testimony of two of Novartis’s expert witnesses, Dr.
    Lawrence Steinman, M.D., and Dr. William Jusko, Ph.D.,
    to make the leap from a 0.3 mg/kg weekly rat dosage to a
    0.5 mg daily human dosage. The court noted that the 0.5
    mg daily dose is also illustrated in the Prophetic Trial. The
    district court concluded that there was sufficient written
    description for the 0.5 mg daily dosage limitation.
    With respect to the written description for the “absent
    an immediately preceding loading dose” limitation, the dis-
    trict court again found sufficient written description in the
    EAE model and the Prophetic Trial. Neither the Prophetic
    Trial nor the EAE model recite a loading dose. The district
    court found that the “Prophetic Trial describes giving a
    ‘daily dosage of 0.5 . . . mg’ fingolimod to treat RRMS,
    started ‘initially.’” J.A. 26 (quoting ’405 patent col. 11 ll.
    8–13). The court found, crediting expert testimony, that,
    “[i]f a loading dose were directed, the Patent would say that
    a loading dose should be administered ‘initially.’” J.A. 26
    (citing J.A. 23334–35 (Tr. 756:16–757:8); J.A. 23441–42
    (Tr. 863:22–864:18)). Similarly, the district court found
    that the “EAE example discloses a dosing regimen which
    does not involve a loading dose.” J.A. 27 (citing J.A. 23345
    (Tr. 767:3–5); J.A. 22793 (Tr. 215:16–21)). Finally, the
    court found that, while the patent describes alternate dos-
    ing regimens, such as “intermittent dosing,” it does not de-
    scribe administering those regimens with loading doses.
    J.A. 27. Thus, the district court concluded, “[t]he EAE
    model and the Prophetic Trial . . . indicate to a person of
    ordinary skill that the claimed invention did not include
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    8       NOVARTIS PHARMACEUTICALS   v. ACCORD HEALTHCARE INC.
    the administration of a loading dose,” and, thus, the patent
    provides sufficient written description of the negative lim-
    itation. J.A. 37–38.
    HEC appeals. We have jurisdiction under 28 U.S.C.
    § 1295(a)(1).
    II.   DISCUSSION
    On appeal, HEC challenges the district court’s deci-
    sions concerning the ’405 patent’s written description of the
    0.5 mg daily dose limitation and the no-loading-dose nega-
    tive limitation. “Whether a claim satisfies the written de-
    scription requirement is a question of fact that, on appeal
    from a bench trial, we review for clear error.” Allergan, Inc.
    v. Sandoz Inc., 
    796 F.3d 1293
    , 1308 (Fed. Cir. 2015) (quot-
    ing Alcon Rsch. Ltd. v. Barr Lab’ys, Inc., 
    745 F.3d 1180
    ,
    1190 (Fed. Cir. 2014)). Under the clear error standard, we
    will not overturn the district court’s factual finding unless
    we have a “‘definite and firm conviction’ that a mistake has
    been made.” Nuvo Pharms. (Ireland) Designated Activity
    Co. v. Dr. Reddy’s Lab’ys Inc., 
    923 F.3d 1368
    , 1376 (Fed.
    Cir. 2019) (quoting Scanner Techs. Corp. v. ICOS Vision
    Sys. Corp. N.V., 
    528 F.3d 1365
    , 1374 (Fed. Cir. 2008)).
    The written description requirement is found in section
    112 of the patent statute, which provides that the patent’s
    specification must contain “a written description of the in-
    vention, and of the manner and process of making and us-
    ing it.” 5   35 U.S.C. § 112(a).     A specification that
    “reasonably conveys to those skilled in the art that the in-
    ventor had possession of the claimed subject matter as of
    the filing date” has adequate written description of the
    claimed invention. Ariad Pharms., Inc. v. Eli Lilly & Co.,
    
    598 F.3d 1336
    , 1351 (Fed. Cir. 2010). “[T]he test requires
    an objective inquiry into the four corners of the
    5  35 U.S.C. § 112(a) also contains the separate “ena-
    blement” requirement, which is not at issue in this appeal.
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    NOVARTIS PHARMACEUTICALS    v. ACCORD HEALTHCARE INC.       9
    specification from the perspective of a person of ordinary
    skill in the art.” Id.
    HEC challenges the district court’s decisions concern-
    ing the ’405 patent’s written description of two limitations:
    the 0.5 mg daily dose limitation and the no-loading-dose
    negative limitation.
    Despite arguing that the inventors did not possess the
    claimed subject matter in 2006, HEC bases its arguments,
    not on the 2006 priority application’s written description,
    but on the ’405 patent’s specification—leaving it to this
    court to independently search the 2006 priority application
    for written description of the claims. HEC’s confusion is
    ultimately of no moment, as we find that the claims have
    adequate written description support in portions of the ’405
    specification which also appear in the 2006 priority appli-
    cation. 6
    A. Written Description for the Dosage Limitation
    HEC argues that, as of the 2006 priority date, the in-
    ventors did not possess a 0.5 mg daily dose of fingolimod.
    It argues that, as of that date, 0.5 mg/day was considered
    too low to be effective to treat RRMS. It describes Novar-
    tis’s calculation of the 0.5 mg/day human dose as derived
    6     Both parties wrongly assume that, if the 2006 pri-
    ority application lacks sufficient written description of the
    ’405 patent’s claims, those claims are invalid. If the 2006
    priority application lacks sufficient written description for
    the ’405 patent’s claims, the ’405 patent’s claims are not
    automatically rendered invalid; they are merely deprived
    of the 2006 priority date. See 35 U.S.C. § 119; see also Paice
    LLC v. Ford Motor Co., 
    881 F.3d 894
    , 906 (Fed. Cir. 2018)
    (“For claims to be entitled to a priority date of an earlier-
    filed application, the application must provide adequate
    written description support for the later-claimed limita-
    tions.”).
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    10   NOVARTIS PHARMACEUTICALS      v. ACCORD HEALTHCARE INC.
    from the lowest disclosed dose in the rat EAE model de-
    scribed in the specification as “undisclosed mathematical
    sleights of hand.” Appellant’s Br. 7. And it argues that the
    Prophetic Trial, which lists a 0.5 mg daily dose along with
    two other dosages, does not provide sufficient written de-
    scription of the 0.5 mg dose. Finally, it asserts that “blaze
    marks” directing a skilled artisan to the 0.5 mg daily dose
    are absent from the ’405 patent.
    We do not find HEC’s arguments convincing. The Pro-
    phetic Trial and the EAE model provide sufficient written
    description to show that, as of the priority date, the inven-
    tors possessed a 0.5 daily fingolimod dosage as claimed in
    the ’405 patent. The Prophetic Trial describes dosing
    RRMS patients with fingolimod hydrochloride at daily dos-
    ages of 0.5, 1.25, or 2.5 mg. ’405 patent col. 11 ll. 8–16. The
    Prophetic Trial’s disclosure of two other dosages does not
    detract from the written description of the claimed dose.
    Nor do disclosures of dosage ranges in other areas of the
    specification lead away from the claimed dose.
    The rat EAE model describes additional information
    which provides further written description for the 0.5
    mg/day limitation. The EAE model describes a dosage of
    0.3 mg/kg per week as effective to “fully block[] disease-as-
    sociated angiogenesis and completely inhibit[] the relapse
    phases.” ’405 patent col. 10 ll. 64–col. 11 ll. 2. The district
    court credited the testimonies of Dr. Steinman and Dr.
    Jusko to arrive at the claimed 0.5 mg/day human dosage
    from the EAE experiment’s 0.3 mg/kg per week rat dosage.
    Those experts both testified that a skilled artisan would
    have converted the lowest daily rat dose described in the
    EAE experiment (0.3 mg/kg weekly) to a daily dose (0.042
    mg/kg daily).     J.A. 24 (citing J.A. 23325–26 (Tr.
    747:6–748:19); J.A. 23443 (Tr. 865:12–24); J.A. 23482 (Tr.
    904:2–18)). The district court found, again based on expert
    testimony, that a skilled artisan “would immediately rec-
    ognize that 0.3 mg/kg weekly (0.042 mg/kg daily) in rats” is
    approximately 60% lower “than the lowest known effective
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    NOVARTIS PHARMACEUTICALS    v. ACCORD HEALTHCARE INC.     11
    dose in the prior art (0.1 mg/kg daily).” J.A. 24–25 (citing
    J.A. 23440–41 (Tr. 862:25–863:21)). It found that a skilled
    artisan “would understand that the EAE results in the ’405
    Patent therefore demonstrate that a proportionally lower
    dose (again, roughly 60% lower) could be effective in hu-
    mans.” J.A. 25 (citing J.A. 23443–45 (Tr. 865:4–867:4); J.A.
    23480–85 (Tr. 902:17–907:8)). It further found that a
    skilled artisan “would understand that the inventors trans-
    lated the lowest dose that had ever been seen as effective
    from their EAE experiment (0.3 mg/kg once per week) to
    the 0.5 dose.”      J.A. 25 (citing J.A. 23356–57 (Tr.
    778:25–779:14)).
    HEC attacks the expert testimony underlying the dis-
    trict court’s determination that the EAE experiment de-
    scribes a 0.5 mg daily human dose as “undisclosed
    mathematical sleights of hand.” Appellant’s Br. 7. We dis-
    agree. A “disclosure need not recite the claimed invention
    in haec verba.” Ariad, 
    598 F.3d at 1352
    . The disclosure
    need only “clearly allow persons of ordinary skill in the art
    to recognize that the inventor invented what is claimed.”
    
    Id. at 1351
    . To accept HEC’s argument would require us
    to ignore the perspective of the person of ordinary skill in
    the art and require literal description of every limitation,
    in violation of our precedent. We find no clear error in the
    district court’s reliance on expert testimony in finding de-
    scription of the 0.5 mg daily human dose in the EAE exper-
    iment results.
    We also reject HEC’s argument that the ’405 patent
    does not have necessary “blaze marks” pointing to the 0.5
    mg daily dose. “Blaze marks” directing an investigator of
    ordinary skill in the art to the claimed species from among
    a forest of disclosed options are not necessary in this case.
    In cases where the specification describes a broad genus
    and the claims are directed to a single species or a narrow
    subgenus, we have held that the specification must contain
    “‘blaze marks’ that would lead an ordinarily skilled inves-
    tigator toward such a species among a slew of competing
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    12   NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.
    possibilities.” Novozymes v. DuPont Nutrition Biosciences
    APS, 
    723 F.3d 1336
    , 1349 (Fed. Cir. 2013).
    “Blaze marks” are not necessary where the claimed
    species is expressly described in the specification, as the
    0.5 mg daily dosage is here. See, e.g., Snitzer v. Etzel, 
    465 F.2d 899
    , 902 (C.C.P.A. 1972) (finding that interference
    counts directed to the activation of a glass laser with triva-
    lent ytterbium ions were adequately described by a specifi-
    cation listing fourteen materials which may be used as
    active laser ingredients, including trivalent ytterbium, and
    noting that “there would seem to be little doubt that the
    literal description of a species provides the requisite legal
    foundation for claiming that species”). The ’405 patent
    does not contain the laundry-list-type disclosures that we
    have found require guidance to direct a skilled artisan to
    the claimed species—it contains the Prophetic Trial listing
    three doses, 0.5, 1.25, and 2.5 mg/day. While other sections
    of the specification disclose larger ranges of potential doses
    for S1P receptor modulators, e.g., 0.1 to 100 mg/day doses,
    those disclosures do not diminish the literal description of
    the 0.5 mg/day dose in the Prophetic Trial. All described
    dose ranges include the 0.5 mg/day dose. And smaller dos-
    age ranges, such as 0.5–30 mg/day, are disclosed for fin-
    golimod hydrochloride. Even if blaze marks were required
    in this case, the Prophetic Trial and 0.5–30 mg/day dosage
    range would provide a skilled artisan more than sufficient
    guidance to direct them to the claimed 0.5 mg/day dose.
    Much of HEC’s argument is directed to its assertion
    that no one, including the inventors, knew that a 0.5
    mg/day dose would be effective as of the 2006 priority date.
    That argument fails for two reasons. First, efficacy is not
    a requirement of the claims. The claims require only ad-
    ministration of a 0.5 mg/day dose for, inter alia, treatment
    purposes. The district court found that the purpose limita-
    tions are adequately described, and HEC has not appealed
    that finding. Thus, cases such as Nuvo Pharms., 
    923 F.3d 1368
    , in which this court found that claims directed to an
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    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.      13
    amount of uncoated PPI that is effective to raise the gastric
    pH to at least 3.5 were not adequately described by a spec-
    ification that “provides nothing more than the mere claim
    that uncoated PPI might work” where skilled artisans
    “would not have thought it would work,” are distinguisha-
    ble. See 
    id. at 1381
    . Second, as explained above, the EAE
    model provides evidence that the inventors knew that a
    60% lower dose would be effective.
    For these reasons, we find no clear error in the district
    court’s holding that the 0.5 mg/day dosage limitation is ad-
    equately described. The district court’s holding is sup-
    ported by the specification and ample expert testimony
    interpreting that specification.
    B. Written Description for the Negative Limitation
    HEC argues that there is no written description of the
    negative limitation because the ’405 specification contains
    no recitation of a loading dose “or its potential benefits or
    disadvantages at all.” Appellant’s Br. 40. It further argues
    that the district court’s finding of written description of the
    negative limitation within the ’405 specification contra-
    dicts the district court’s finding that Kappos 2006, which is
    similarly silent as to loading doses, does not anticipate the
    claims. We find both arguments unavailing.
    It is well established that there is no “new and height-
    ened standard for negative claim limitations.” Inphi Corp.
    v. Netlist, Inc., 
    805 F.3d 1350
    , 1356 (Fed. Cir. 2015). We
    are aware of no case that suggests otherwise. And, while
    HEC asserts that “[i]t is well-settled law that silence alone
    cannot serve as a basis for” a negative limitation, Appel-
    lant’s Br. 41, HEC identifies no case that actually supports
    that proposition. To the contrary, we repeatedly have re-
    sisted imposition of heightened written description stand-
    ards for negative limitations, such as that urged by HEC.
    For example, in Santarus, Inc. v. Par Pharmaceutical,
    Inc., we found that claims directed to a method of
    Case: 21-1070    Document: 41      Page: 14     Filed: 01/03/2022
    14   NOVARTIS PHARMACEUTICALS      v. ACCORD HEALTHCARE INC.
    treatment with a pharmaceutical composition containing
    no sucralfate were adequately described by a specification
    that explained that, although sucralfate is “possibly the
    ideal agent for stress ulcer prophylaxis,” it was known to
    have occasional adverse effects. 
    694 F.3d 1344
    , 1350–51
    (Fed. Cir. 2012). In Santarus, as in this case, there was
    expert testimony providing a person of ordinary skill’s un-
    derstanding of the patent specification. See 
    id. at 1351
    .
    The expert testimony in Santarus showed that “a person of
    ordinary skill in this field . . . would have understood from
    the specification that disadvantages of sucralfate may be
    avoided by the [claimed] formulation.” 
    Id.
     We explained
    that “[n]egative claim limitations are adequately supported
    when the specification describes a reason to exclude the rel-
    evant limitation.” 
    Id.
     We did not hold that a specification
    must describe a reason to exclude a negative limitation. A
    specification that describes a reason to exclude the relevant
    negative limitation is but one way in which the written de-
    scription requirement may be met.
    In In re Bimeda Research. & Development Ltd., we held
    that a claim that excluded a specific anti-infective, acrifla-
    vine, was not adequately described by a disclosure that was
    inconsistent with the exclusion of acriflavine but not other
    anti-infectives or antibiotics. 
    724 F.3d 1320
    , 1324 (Fed.
    Cir. 2013). The claim at issue in Bimeda was directed to a
    method of preventing mastitis in dairy cows by sealing the
    teat canal of a cow’s mammary gland with a seal formula-
    tion that excludes acriflavine. Other claims in the same
    patent excluded all anti-infective agents. We noted that
    the patent repeatedly distinguished the invention as able
    to prevent mastitis without the use of antibiotics. Based
    on the written description’s consistent description of the in-
    vention’s non-antibiotic approach to preventing mastitis,
    we concluded that the patent’s disclosure was “inconsistent
    with a claim which excludes acriflavine, but not the pres-
    ence of other antiinfectives or antibiotics.” 
    Id.
     (citation and
    quotation marks omitted). We did not require that the
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    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.      15
    specification describe a reason to exclude acriflavine spe-
    cifically, but, rather, found only that a negative limitation
    which is inconsistent with the disclosure is not adequately
    described.
    In Inphi, we confirmed that the written description re-
    quirement is satisfied where “‘the essence of the original
    disclosure’ conveys the necessary information—‘regardless
    of how it’ conveys such information, and regardless of
    whether the disclosure’s ‘words [a]re open to different in-
    terpretation[s].’” 805 F.3d at 1354 (quoting In re Wright,
    
    866 F.2d 422
    , 424–25 (Fed. Cir. 1989) (citation and internal
    quotation marks omitted)). We explained that “Santarus
    simply reflects the fact that the specification need only sat-
    isfy the requirements of § 112, paragraph 1 as described in
    this court’s existing jurisprudence[.]” Id. at 1356. And we
    noted that the “‘reason’ required by Santarus is provided,
    for instance, by properly describing alternative features of
    the patented invention.” Id. (citing In re Johnson, 
    558 F.2d 1008
    , 1019 (C.C.P.A. 1977)).
    In Inphi, we found that substantial evidence supported
    the Patent Trial and Appeal Board’s (“Board”) finding that
    a negative limitation which had been added during prose-
    cution (“DDR chip selects that are not CAS, RAS, or bank
    address signals”) was adequately described by an original
    specification which did not expressly articulate a reason to
    exclude RAS and CAS signals. We found the Board’s deci-
    sion was supported by evidence of (1) standards set by the
    Joint Electron Device Engineering Council, a global stand-
    ard setting body for the microelectronics industry, incorpo-
    rated by reference in the patent, which specify that DDR
    signals, including CS, RAS, CAS, and bank address sig-
    nals, are distinct from each other; (2) a table in the specifi-
    cation which excludes RAS and CAS signals; and (3)
    various passages from the specification, including a figure
    which distinguishes chip select signals, command signals
    (including RAS and CAS signals) and bank address signals.
    We concluded that the specification’s disclosure of
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    16   NOVARTIS PHARMACEUTICALS      v. ACCORD HEALTHCARE INC.
    alternative features was sufficient to satisfy the written de-
    scription standard for the negative limitation. 
    Id. at 1357
    .
    In Nike, Inc. v. Adidas AG, we reiterated that Santarus
    did not create a heightened standard for written descrip-
    tion of negative limitations. 
    812 F.3d 1326
    , 1348 (Fed. Cir.
    2016), overruled on other grounds by Aqua Prods., Inc. v.
    Matal, 
    872 F.3d 1290
     (Fed. Cir. 2017). We stated that neg-
    ative limitations, like all other limitations, are held to “the
    customary standard for the written description require-
    ment.” 
    Id.
     In Nike, we found a limitation of “flat knit
    edges,” which Adidas characterized as a negative limita-
    tion, was adequately described by three figures in the spec-
    ification depicting the claimed textile element which Nike’s
    expert opined could be made using flat knitting in contrast
    to another figure’s textile element which is formed using a
    circular knitting machine. 
    Id.
     at1348–49.
    Similarly, in Erfindergemeinschaft Uropep GBR v. Eli
    Lilly & Co., Judge Bryson, sitting by designation in the
    Eastern District of Texas, explained that the law does not
    require that the disclosure explain a negative limitation.
    
    276 F. Supp. 3d 629
    , 657–58 (E.D. Tex. 2017), aff’d, 739 F.
    App’x 643 (Fed. Cir. 2018). Judge Bryson explained, citing
    Bimeda, that “[w]hat is prohibited is a negative limitation
    that is contrary to the thrust of the invention.” 
    Id. at 658
    .
    He noted that “a patentee can choose to claim any particu-
    lar embodiments identified in the specification and exclude
    others, without explanation, as long as the claim does not
    indicate to persons of skill that it covers embodiments in-
    consistent with, and therefore unsupported by, the disclo-
    sure.” 
    Id.
    In asserting that “silence alone cannot serve as a basis
    for” a negative limitation, Appellant’s Br. 41, HEC at-
    tempts to create a new heightened written description
    standard for negative limitations. In doing so, it ignores a
    central tenet of our written description jurisprudence—
    that the disclosure must be read from the perspective of a
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    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.      17
    person of skill in the art—as well as precedent stating that
    the disclosure need not describe a limitation in haec verba.
    See, e.g., All Dental Prodx, LLC v. Advantage Dental Prod.,
    Inc., 
    309 F.3d 774
    , 779 (Fed. Cir. 2002) (“[T]he failure of
    the specification to specifically mention a limitation that
    later appears in the claims is not a fatal one when one
    skilled in the art would recognize upon reading the specifi-
    cation that the new language reflects what the specifica-
    tion shows has been invented.” (citing Eiselstein v. Frank,
    
    52 F.3d 1035
    , 1039 (Fed. Cir. 1995)); see also Ariad, 
    598 F.3d at 1351
    . In other words, context and the knowledge
    of those skilled in the art matter. And, as the Supreme
    Court has made clear, when assessing what the written de-
    scription reveals to a skilled artisan, common sense also
    matters. KSR Int’l Co. v. Teleflex Inc., 
    550 U.S. 398
    , 421
    (2007) (holding that, in an obviousness analysis, “[r]igid
    preventative rules that deny factfinders recourse to com-
    mon sense, however, are neither necessary under our case
    law nor consistent with it”).
    The dissent notes that the Manual of Patent Examin-
    ing Procedure (“MPEP”) 7 states: “The mere absence of a pos-
    itive recitation is not a basis for an exclusion.” MPEP
    § 2173.05(i). As the dissent puts it—“silence alone is insuffi-
    cient.” Dissent at 4. Both the MPEP and the dissent are
    correct in their statement of the law: the “mere absence of
    a positive recitation” is not enough and “silence alone is in-
    sufficient.” But the dissent, like HEC, ignores that it is
    how a skilled artisan reads a disclosure that matters. Writ-
    ten description may take any form, so long as a skilled ar-
    tisan would read the disclosure as describing the claimed
    invention.
    Our case law makes clear that “[c]ompliance with the
    written description requirement is essentially a fact-based
    7  The MPEP is not binding on this court but may be
    persuasive.
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    18   NOVARTIS PHARMACEUTICALS      v. ACCORD HEALTHCARE INC.
    inquiry that will ‘necessarily vary depending on the nature
    of the invention claimed.’” Enzo Biochem, Inc. v. Gen-Probe
    Inc., 
    323 F.3d 956
    , 963 (Fed. Cir. 2002) (quoting Vas-Cath
    Inc. v. Mahurkar, 
    935 F.2d 1555
    , 1562 (Fed. Cir. 1991)).
    The MPEP similarly provides for written description in
    various forms. In addition to stating that the “mere ab-
    sence of a positive recitation” is not enough, the MPEP also
    correctly states that no specific form of disclosure is re-
    quired and provides for implicit written description. MPEP
    § 2173.05(i) states that “a lack of literal basis in the speci-
    fication for a negative limitation may not be sufficient to
    establish a prima facie case for lack of descriptive support.”
    And MPEP § 2163 states that “newly added claims or claim
    limitations must be supported in the specification through
    express, implicit, or inherent disclosure.” MPEP § 2163
    (emphasis added). What is critical is how a person of skill
    in the art would read the disclosure—not the exact words
    used.
    HEC and the dissent urge us to elevate form over sub-
    stance by creating a new rule that a limitation which is not
    expressly recited in the disclosure is never adequately de-
    scribed, regardless of how a skilled artisan would read that
    disclosure. As we have several times before, we reject the
    invitation to create a heightened written description stand-
    ard for negative limitations. As with all other limitations,
    the negative limitation here must be accompanied by an
    original disclosure which conveys to a person of ordinary
    skill that the inventor was in possession of the claimed in-
    vention. See Ariad, 
    598 F.3d at 1351
    . And, as in all other
    written description challenges, HEC was required to show
    by clear and convincing evidence that the negative limita-
    tion was not adequately described. The district court did
    not clearly err in finding that HEC failed to do so.
    In determining that there is adequate written descrip-
    tion of the negative limitation, the district court correctly,
    and quite carefully, conducted “an objective inquiry into
    the four corners of the specification from the perspective of
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    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.      19
    a person of ordinary skill in the art” as required by our
    precedent. See Ariad, 
    598 F.3d at 1351
    . We review the
    evidence cited by the district court below and discern no
    clear error in the court’s analysis or conclusions.
    The Prophetic Trial describes giving RRMS patients
    fingolimod hydrochloride “at a daily dosage of 0.5, 1.25 or
    2.5 mg p.o.” ’405 patent col. 11 ll. 8–9. It further states
    that: “Initially patients receive treatment for 2 to 6
    months.” 
    Id.
     col. 11 ll. 13–14. Dr. Steinman, one of Novar-
    tis’s expert witnesses, testified from the perspective of a
    skilled artisan that, if the Prophetic Trial included a load-
    ing dose, the patent would explicitly state as much:
    “[T]here were two places where if there were going
    to be a loading dose, you would explicitly state it.
    ....
    So the first place one might explicitly say there
    was—there was a preceding loading dose is when
    you described the daily dosage, the reason being a
    loading dose would occur before the first daily dose.
    The second place is even more dramatic, because
    they say, “Initially patients received treatment for
    2 to 6 months.” So now they’re really zooming in
    on Day 1, what is that treatment, it’s a daily dose
    of 0.5.
    So there were two perfectly logical places that if
    there was going to be a loading dose, it would have
    been stated.
    ....
    That’s where you would put it if you were going to
    give a loading dose.
    J.A. 23343 (Tr. 765:2–25).
    Similarly, Dr. Fred Lublin, Ph.D., another expert testi-
    fying for Novartis, testified that a person of skill in the art
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    20   NOVARTIS PHARMACEUTICALS    v. ACCORD HEALTHCARE INC.
    “would have viewed the patent as a document, as a com-
    plete document, that should give you all the information
    you need to carry out the claims, and that information of
    having a loading dose is not there, and what’s instead there
    is examples of daily dose, daily dose, daily dose.” J.A.
    22791 (Tr. 213:6–15). Dr. Lublin testified that a “loading
    dose is a greater than normal dose that you give until you
    return to a maintenance dose” and a loading dose is “not a
    daily dose.” J.A. 22792 (Tr. 214:1–9). He further testified
    that “[o]ne would expect in a patent that if there was going
    to be a loading dose, it would be specified.” J.A. 22793 (Tr.
    215:5–8). And a third expert testifying for Novartis, Dr.
    Jusko, similarly testified that, from the perspective of a
    person of skill in pharmacology, the Prophetic Trial has a
    “specified initial regimen that does not include a loading
    dose.” J.A. 23442 (Tr. 864:14–16).
    The district court credited this expert testimony, as
    well as the testimony from HEC’s own expert, Dr. Paul
    Hoffman, M.D., who agreed that “a loading dose is a higher-
    than-therapeutic level dose, usually given . . . as the first
    dose.” J.A. 23125 (Tr. 547:14–18); J.A. 27. Based on that
    evidence, the court concluded that the “absence of an im-
    mediately preceding loading dose from the specification,
    and from the Prophetic Trial, would tell a person of skill
    that loading doses are excluded from the invention.” J.A.
    26. We discern no clear error in that finding. The district
    court further noted that the rat EAE experiment does not
    describe a loading dose. J.A. 26. It again credited the tes-
    timony of multiple expert witnesses who testified that the
    EAE model did not include a loading dose. J.A. 26. Dr.
    Jusko, in response to a question about whether there are
    any loading doses in the EAE model, stated: “Not that I’m
    aware of.” J.A. 22793 (Tr. 215:16–21). Dr. Steinman simi-
    larly testified that no loading dose was used in the EAE
    experiment. J.A. 23345 (Tr. 767:3–5). HEC’s own expert
    witness, Dr. Hoffman, testified that the EAE model does
    not talk about a loading dose. J.A. 23209 (Tr. 631:18–22).
    Case: 21-1070    Document: 41      Page: 21     Filed: 01/03/2022
    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.      21
    Based on both the specification’s disclosure of the rat EAE
    model and the ample expert testimony providing evidence
    of how a person of ordinary skill would read that disclosure,
    the district court concluded that the “EAE example dis-
    closes a dosing regimen which does not involve a loading
    dose.” J.A. 27. Finally, the district court noted that, while
    the patent “describes alternative dosing regimens, like ‘in-
    termittent dosing,’ [it] does not describe loading doses.”
    J.A. 27.
    The district court concluded that the “EAE model and
    the Prophetic Trial . . . both indicate to a person of ordinary
    skill that the claimed invention did not include the admin-
    istration of a loading dose.” J.A. 37–38. We are not left
    with the “definite and firm conviction” that the district
    court made a mistake in coming to this conclusion. See
    Nuvo Pharms., 923 F.3d at 1376 (quoting Scanner Techs.,
    
    528 F.3d at 1374
    ). To the contrary, the district court’s con-
    clusion appears wholly correct. To arrive at the opposite
    conclusion would require us to disregard the perspective of
    a person of skill in the art—something our precedent
    simply does not allow. See Ariad, 
    598 F.3d at 1351
    .
    We also find unpersuasive HEC’s argument that the
    district court’s written description decision contradicts its
    determination that the ’405 patent is not anticipated by
    Kappos 2006. HEC notes that neither Kappos 2006 nor the
    ’405 patent’s specification explicitly state that a loading
    dose should not be administered. But HEC’s argument ig-
    nores the differences between the two district court find-
    ings and ignores the differences between the disclosures of
    Kappos 2006 and the ’405 specification.
    As a granted patent, the ’405 patent is presumed valid.
    Thus, it is also presumed to have a complete written de-
    scription. See Nat’l Recovery Techs., Inc. v. Magnetic Sep-
    aration Sys, Inc., 
    166 F.3d 1190
    , 1195 (Fed. Cir. 1999)
    (“The presumption of validity includes a presumption that
    the patent complies with § 112.”). No such presumption
    Case: 21-1070    Document: 41      Page: 22     Filed: 01/03/2022
    22   NOVARTIS PHARMACEUTICALS      v. ACCORD HEALTHCARE INC.
    applies to disclosures of a prior art reference that is not it-
    self a granted patent, such as Kappos 2006. Further, the
    perspective of a person of skill in the art is important in
    both the written description and the anticipation inquiries.
    And, in this case, the district court credited the testimony
    of two expert witnesses, Dr. Lublin and Dr. Steinman, who
    testified that a person of skill in the art would not presume
    that the Kappos 2006 abstract was complete. J.A. 30 (cit-
    ing J.A. 22782 (Tr. 204:12–19) (Dr. Lublin testifying that
    abstracts “have to by design” leave out information describ-
    ing clinical trials); J.A. 23475 (Tr. 897:1–5) (Dr. Steinman
    testifying that “an abstract, like a press release, like any
    kind of announcement, is inherently incomplete,” while “a
    publication and a patent are presumed complete”)). Thus,
    although neither the ’405 specification nor Kappos 2006 in-
    clude the phrase “loading dose,” it was not clear error for
    the district court to find that a skilled artisan would read
    the specification as not including a loading dose and would
    read Kappos 2006 as silent on the presence or absence of a
    loading dose.
    Differences between the ’405 patent’s specification and
    Kappos 2006 justify the district court’s findings that the
    specification describes the absence of a loading dose while
    Kappos 2006 does not anticipate that negative limitation.
    The specification includes the Prophetic Trial, which the
    district court found “describes giving a ‘daily dosage of 0.5
    . . . mg’ fingolimod to treat RRMS, started ‘initially.’” J.A.
    26. The district court found that, “[o]n this record, starting
    with a daily dose plainly implies that there is no loading
    dose.” J.A. 27. Kappos 2006 consists of two paragraphs
    describing a planned clinical trial and, with respect to dos-
    ing, states only that “[a]pproximately 1.100 patients . . .
    are being randomised in a 1:1:1 ratio to once-daily fin-
    golimod 1.25 mg, fingolimod 0.5 mg, or placebo, for up to 24
    months.” J.A. 24723–24. Kappos 2006 nowhere says that
    the daily fingolimod dosage should be “initially” adminis-
    tered. Thus, differences between Kappos 2006 and the ’405
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    NOVARTIS PHARMACEUTICALS      v. ACCORD HEALTHCARE INC.       23
    patent justify the district court’s conclusions that Kappos
    2006 does not anticipate the claims and the ’405 specifica-
    tion adequately describes the claims.
    The dissent takes umbrage with the district court’s
    finding that the “Prophetic Trial describes giving a ‘daily
    dosage of 0.5 . . . mg’ fingolimod to treat RRMS, started ‘in-
    itially’” because the ’405 patent says “[i]nitially, patients re-
    ceive treatment for 2 to 6 months.” Dissent at 6–7; J.A. 26;
    ’405 patent col. 11 ll. 13–14. The dissent would find that the
    “word ‘initially’ is not modifying the daily dosage; it is modi-
    fying the initial length of treatment in this example.” Dissent
    at 6–7. The dissent, thus, would substitute its own factual
    findings for those of the district court. But, if the 2–6 month
    “initial” dose does not differ in any way from the previously
    described daily doses, the language, used in context, must ex-
    clude a loading dose. As we have already explained, the dis-
    trict court did not clearly err in finding that the “Prophetic
    Trial describes giving a ‘daily dosage of 0.5 . . . mg’ fin-
    golimod to treat RRMS, started ‘initially.’” J.A. 26. And we
    are not free to substitute our own factual findings for those of
    the district court absent clear error because “a district court
    judge who has presided over, and listened to, the entire pro-
    ceeding has a comparatively greater opportunity to gain the
    necessary ‘familiarity with specific scientific problems and
    principles,’ . . . than an appeals court judge who must read a
    written transcript or perhaps just those portions referenced
    by the parties.” Teva Pharms. USA, Inc. v. Sandoz, Inc., 
    574 U.S. 318
    , 319 (2015) (quoting Graver Tank & Mfg. Co. v.
    Linde Air Prods. Co., 
    339 U.S. 605
    , 610 (1950)).
    The dissent also asserts that, on this record, the term
    “daily dose” would not convey to a skilled artisan that no
    loading dose should be used. Dissent at 7–8. But the dis-
    trict court’s decision did not rely only on the term “daily
    dose.” Rather, as noted above, the district court found that
    “starting with a daily dose plainly implies that there is no
    loading dose,” as a loading dose is a larger-than-daily dose.
    J.A. 27 (emphasis added). We need not, and do not, go
    Case: 21-1070     Document: 41      Page: 24    Filed: 01/03/2022
    24   NOVARTIS PHARMACEUTICALS      v. ACCORD HEALTHCARE INC.
    further than the district court to make findings about the
    term “daily dose.” The dissent’s assertion to the contrary
    and allegation that we “tease[] an entirely new claim limi-
    tation out of an entirely common term, relegating the legal
    determination of a term’s meaning to the backseat of an
    expert’s post-hoc rationalization” is, frankly, baffling. See
    Dissent at 8.
    Written description in this case, as in all cases, is a fac-
    tual issue. In deciding that the district court did not clearly
    err in finding written description for the negative limita-
    tion in the ’405 patent, we do not establish a new legal
    standard that silence is disclosure, as the dissent asserts.
    Instead, we merely hold that, on this record, the district
    court did not clearly err in finding that a skilled artisan
    would read the ’405 patent’s disclosure to describe the “ab-
    sent an immediately preceding loading dose” negative lim-
    itation.
    III.   CONCLUSION
    For the foregoing reasons, we affirm the district court’s
    decision.
    AFFIRMED
    Case: 21-1070   Document: 41    Page: 25   Filed: 01/03/2022
    United States Court of Appeals
    for the Federal Circuit
    ______________________
    NOVARTIS PHARMACEUTICALS CORPORATION,
    Plaintiff-Appellee
    v.
    ACCORD HEALTHCARE, INC., AUROBINDO
    PHARMA LTD., AUROBINDO PHARMA USA, INC.,
    DR. REDDY’S LABORATORIES, INC., DR. REDDY’S
    LABORATORIES, LTD., EMCURE
    PHARMACEUTICALS LTD., HERITAGE
    PHARMACEUTICALS INC., GLENMARK
    PHARMACEUTICALS INC., USA, GLENMARK
    PHARMACEUTICALS LIMITED, HETERO USA,
    INC., HETERO LABS LIMITED UNIT-V, HETERO
    LABS LIMITED, MYLAN PHARMACEUTICALS,
    INC., PRINSTON PHARMACEUTICAL INC.,
    STRIDES GLOBAL PHARMA PRIVATE LIMITED,
    STRIDES PHARMA, INC., TORRENT PHARMA
    INC., TORRENT PHARMACEUTICALS LTD.,
    ZYDUS PHARMACEUTICALS (USA) INC., CADILA
    HEALTHCARE LTD., APOTEX INC., APOTEX
    CORP., SUN PHARMACEUTICAL INDUSTRIES,
    LTD., SUN PHARMACEUTICAL INDUSTRIES INC.,
    SUN PHARMA GLOBAL FZE,
    Defendants
    HEC PHARM CO., LTD., HEC PHARM USA INC.,
    Defendants-Appellants
    ______________________
    2021-1070
    ______________________
    Case: 21-1070    Document: 41      Page: 26    Filed: 01/03/2022
    2    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.
    Appeal from the United States District Court for the
    District of Delaware in No. 1:18-cv-01043-KAJ, Circuit
    Judge Kent A. Jordan.
    ______________________
    MOORE, Chief Judge, dissenting.
    The majority dramatically expands a patentee’s ability
    to add, years after filing a patent application, negative
    claim limitations that have zero support in the written de-
    scription. By doing so, it contradicts our well-established
    precedent and nullifies the Patent Office’s guidance in the
    Manual of Patent Examining Procedure (MPEP). I would
    reverse the district court’s finding that there exists written
    description support as it is inconsistent with our estab-
    lished precedent. Silence is not disclosure.
    I
    “The hallmark of written description is disclosure.” Ar-
    iad Pharms., Inc. v. Eli Lilly & Co., 
    598 F.3d 1336
    , 1351
    (en banc). The description in the specification must clearly
    allow a skilled artisan to recognize that the inventor in-
    vented what is claimed. 
    Id.
     The ’405 patent contains no
    written description support for the limitation “absent an
    immediately preceding loading dose regimen.” This nega-
    tive limitation was added in response to an obviousness re-
    jection during prosecution of the ’405 patent’s co-pending
    parent application. J.A. 23892–94. Claim 1:
    1. A method for reducing or preventing or alleviat-
    ing relapses in Relapsing-Remitting multiple scle-
    rosis in a subject in need thereof, comprising orally
    administering to said subject 2-amino-2-[2-(4-oc-
    tylphenyl)ethyl]propane-1,3-diol, in free form or in
    a pharmaceutically acceptable salt form, at a daily
    dosage of 0.5 mg, absent an immediately preceding
    loading dose regimen.
    Case: 21-1070     Document: 41      Page: 27    Filed: 01/03/2022
    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.        3
    There is no disclosure in the specification of preventing
    a loading dose. Loading doses—whether to be used or not—
    are never discussed. As the majority concedes, we have
    long held that silence cannot support a negative limitation;
    for if the specification is silent there is no evidence that the
    inventor actually possessed the invention. Maj. at 17
    (“Both the MPEP and the dissent are correct in their state-
    ment of the law: the ‘mere absence of a positive recitation’
    is not enough, and ‘silence alone is insufficient.’”). “Nega-
    tive claim limitations are adequately supported when the
    specification describes a reason to exclude the relevant lim-
    itation,” such as by listing the disadvantages of some em-
    bodiment. Santarus, Inc. v. Par Pharm., Inc., 
    694 F.3d 1344
    , 1351 (Fed. Cir. 2012). In Inphi Corp. v. Netlist, Inc.,
    
    805 F.3d 1350
    , 1356 (Fed. Cir. 2015), we explained that re-
    citing alternative features of the patented invention may
    also suffice. 1 In Nike, Inc. v. Adidas AG, we again reiter-
    ated that the specification should indicate a reason to ex-
    clude. 
    812 F.3d 1326
    , 1348 (Fed. Cir. 2016). This law, our
    law, does not create a heightened standard for negative
    claim limitations; it simply requires some disclosure to
    demonstrate that the inventor was not, as in this case, am-
    bivalent about loading doses. 2
    1    Erfindergemeinschaft Uropep GBR v. Eli Lilly &
    Co., 
    276 F. Supp. 3d 629
    , 657–59 (E.D. Tex. 2017), con-
    sistent with Inphi, holds that when a patent discloses
    many alternatives, the claims are permitted to claim only
    some and exclude others. The specification here does not
    disclose alternatives (some with and some without loading
    doses).
    2   In re Bimeda Research & Development Ltd., 
    724 F.3d 1320
    , 1323–24 (Fed. Cir. 2013), does not help the ma-
    jority at all. The court simply held that, when the patent
    repeatedly emphasizes that the invention was “without
    Case: 21-1070     Document: 41      Page: 28    Filed: 01/03/2022
    4    NOVARTIS PHARMACEUTICALS      v. ACCORD HEALTHCARE INC.
    Following our clear precedent, the Patent Office’s
    MPEP provides the following guidance: “The mere absence
    of a positive recitation is not a basis for an exclusion,” i.e.,
    silence alone is insufficient. MPEP § 2173.05(i). That re-
    mains true even if it would have been obvious to a skilled
    artisan to exclude the undisclosed feature. Rivera v. Int’l
    Trade Comm’n, 
    857 F.3d 1315
    , 1322 (Fed. Cir. 2017) (“The
    knowledge of ordinary artisans may be used to inform what
    is actually in the specification, but not to teach limitations
    that are not in the specification, even if those limitations
    would be rendered obvious by the disclosure.”).
    Nowhere in the patent does it say a loading dose should
    not be administered. Nowhere does it discuss alternatives
    (including or not including a loading dose). Nowhere does
    it give advantages or disadvantages of including a loading
    dose. Indeed, it provides no reason to exclude a loading
    dose. Even Novartis’ expert, Dr. Lublin, agreed:
    Q: Nothing in the text of the specification of the
    ’405 patent discloses a rationale for the negative
    limitation prohibiting an immediately preceding
    loading dose, correct?
    A: I don’t believe so.
    J.A. 22872–73. And all the experts agreed that loading
    doses are sometimes given to MS patients. See J.A. 22780
    (Dr. Lublin explaining that loading doses have been used
    in trials of MS drugs and with fingolimod in particular);
    J.A. 22794; J.A. 23347–48 (Dr. Steinman, Novartis’ second
    physician expert, acknowledging that loading doses are
    used in MS treatments); J.A. 23475 (Dr. Jusko, Novartis’
    pharmacology expert, testifying that fingolimod was given
    to transplant patients with a loading dose, and that he
    “could envision the possibility of starting with a loading
    using antibiotics,” a claim which allows some antibiotics
    lacks written description support. 
    Id.
    Case: 21-1070    Document: 41      Page: 29    Filed: 01/03/2022
    NOVARTIS PHARMACEUTICALS    v. ACCORD HEALTHCARE INC.       5
    dose”). The ’405 patent provides nothing to signal to the
    public that the inventors possessed a treatment excluding
    a loading dose when a loading dose was a known possibil-
    ity.
    The patent is silent, eerily silent. Consistent with San-
    tarus, Inphi, and Nike, there needed to be some discussion
    of loading doses in order to show that the inventors in fact
    invented this treatment method that is not just ambivalent
    to, but expressly excludes, a loading dose. This is not a
    heightened written description requirement; it is simply a
    written description requirement.
    The district court relied on the disclosure’s silence to
    support the negative loading dose limitation, reasoning
    that silence “would tell a person of skill that loading doses
    are excluded from the invention.” J.A. 26 ¶ 61. We have
    rejected the notion that a skilled artisan’s knowledge can
    speak for a mute specification. See Rivera, 857 F.3d at
    1322. Here, the expert that the majority relies upon to sup-
    plement a silent disclosure concludes that a loading dose is
    excluded because the patent is silent on loading doses: “the
    patent [i]s a document, as a complete document, that
    should give you all the information you need to carry out
    the claims, and that information of having a loading dose
    is not there.” Maj. at 19–20 (quoting J.A. 22791). If silence
    were sufficient then every later-added negative limitation
    would be supported as long as the patent makes no men-
    tion of it. This is a fundamental error of law.
    Novartis explained its support for the no-loading-dose
    limitation as follows:
    Judge Linn: There is nothing in the patent that
    says treatment begins with the daily dose?
    Novartis: Ummm the prophetic example says
    treatment begins initially and treatment is the 0.5
    mg daily dose so if that begins initially it excludes
    the possibility of a loading dose.
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    6     NOVARTIS PHARMACEUTICALS       v. ACCORD HEALTHCARE INC.
    ***
    Chief Judge Moore: The patent says “Initially, pa-
    tients receive treatment for 2 to 6 months,” and you
    believe I should construe that as initially there is
    no loading dose?
    Novartis: Yes, your honor a loading dose is ex-
    cluded from that treatment.
    Oral Argument at 35:30–37:13. The majority claims that
    the Prophetic Example in the specification describes
    “start[ing] ‘initially’” by “giving a ‘daily dose of 0.5 . . . mg.’”
    Maj. at 7; Maj. at 22 (same). This is a false and inaccurate
    quotation. The word “initially” does not precede or modify
    the daily dosage sentence; it follows it three full sentences
    later. To be clear, the patent does NOT say treatment be-
    gins initially with a daily dose. Here is the actual quote:
    20 patients with relapsing-remitting MS receive
    said compound at a daily dosage of 0.5, 1.25 or 2.5
    mg p.o. The general clinical state of the patient is
    investigated weekly by physical and laboratory ex-
    amination. Disease state and changes in disease
    progression are assessed every 2 months by radio-
    logical examination (MRI) and physical examina-
    tion. Initially, patients receive treatment for 2 to 6
    months. Thereafter, they remain on treatment for
    as long as their disease does not progress and the
    drug is satisfactorily tolerated.
    ’405 patent at 11:8–16. The word “initially” is not some
    complex, scientific term in need of expert explanation. It is
    basic English. The word “initially” is not modifying the
    daily dosage; it is modifying the initial length of treatment
    Case: 21-1070    Document: 41      Page: 31    Filed: 01/03/2022
    NOVARTIS PHARMACEUTICALS    v. ACCORD HEALTHCARE INC.       7
    in this example. 3 To the extent that the district court
    reached a fact finding to the contrary, it is inconsistent
    with the straight-forward, quite clear language of the pa-
    tent and therefore clearly erroneous. 4
    Novartis also claims that the use of the term “daily dos-
    age” itself would convey to a skilled artisan that no loading
    dose should be used. This is not only unsupported by the
    record; it is contradicted at every turn. First, the claim al-
    ready said “daily dosage” before the negative limitation
    was added. It was allowed only after the applicants added
    the no loading dose limitation. J.A. 23903 (Examiner’s re-
    jection in parent application); J.A. 23892–93 (Applicant
    Response in same); see also Novartis Br. 11–12. The appli-
    cants explained they added the no-loading-dose limitation
    “to specify that the [daily dosage] cannot immediately fol-
    low a loading dose regiment. Applicants have made these
    amendments to further distinguish their claims from the
    disclosure of [the prior art].” J.A. 23892. 5 If daily already
    meant no loading dose, then there would have been no rea-
    son for the claims to recite both a “daily dosage” and the
    negative loading dose limitation. The same logic applies to
    3    I note that even if the Prophetic Example were to
    be understood as not having included a loading dose that
    does not mean that loading doses must be prohibited (as
    the claims now require).
    4   Nothing about this analysis “substitute[s] . . . fac-
    tual findings for those of the district court.” Maj. at 23.
    Instead, it merely points out how it is clear error for the
    majority, district court, and Novartis to misquote the spec-
    ification.
    5   Novartis stated during argument that this limita-
    tion was “added to clarify that the claim does not overlap
    with [the prior art].” Oral Argument at 21:34–41. This lit-
    igation claim cannot be reconciled with their own prosecu-
    tion statements.
    Case: 21-1070    Document: 41      Page: 32    Filed: 01/03/2022
    8    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.
    the specification, which only mentioned “daily dosage.”
    This prosecution makes clear that neither the applicant
    nor the examiner believed that the use of the term “daily
    dosage” alone conveyed the absence of a loading dose.
    There is no evidence that daily had a special meaning
    in the field of pharmacology. Daily is not a complex or com-
    plicated term of art that requires expert testimony to ex-
    plain. The district court construed the claim term “daily
    dosage of 0.5 mg” to mean “the amount of drug that some-
    one takes in a given day.” J.A. 18670. Neither party ar-
    gued the term excludes a loading dose. Id. And for good
    reason—it has a plain meaning, and the prosecution his-
    tory shows it does not implicitly exclude a loading dose.
    Novartis backdoors a claim construction argument, argu-
    ing that “experts understood the patent’s description of a
    ‘daily dose’ as exclusive of a loading dose,” Novartis Br. 46,
    but it and the district court already defined daily dosage
    otherwise.
    Rather than defend Novartis’ reliance on the “daily
    dosage” language, the majority pivots to focus on the dis-
    trict court’s statement that “starting with a daily dose
    plainly implies that there is no loading dose.” Maj. at 23–
    24 (quoting J.A. 27). But that statement is just another
    example of the district court (and now the majority) rewrit-
    ing the specification with expert testimony. The patent
    never says “starting with a daily dose,” and the district
    court relied exclusively on expert testimony to support that
    finding. See J.A. 27 (citing J.A. 23344). But “[t]he
    knowledge of ordinary artisans may . . . not [be used] to
    teach limitations that are not in the specification[.]” Ri-
    vera, 857 F.3d at 1322. Novartis, and now the majority,
    teases an entirely new claim limitation out of an entirely
    common term, relegating the legal determination of a
    term’s meaning to the backseat of an expert’s post-hoc ra-
    tionalization.
    Case: 21-1070     Document: 41      Page: 33    Filed: 01/03/2022
    NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.        9
    In fact, the district court found that a nearly identical
    disclosure in the prior art (Kappos 2006, a Novartis-sup-
    ported study) did not anticipate because it failed to disclose
    the negative loading dose limitation. Kappos disclosed a
    study administering 0.5 mg fingolimod to RRMS patients
    “once-daily fingolimod for up to 24 months.” J.A. 29–30
    ¶ 72; J.A. 24724. The district court found Kappos 2006 did
    not meet the negative loading-dose limitation, reasoning
    that “[t]he failure to mention a loading dose does not . . .
    indicate that the dose was not present in the trial, but only
    that the presence or absence of a loading dose was not men-
    tioned.” J.A. 30 ¶ 74. A district court’s “internally incon-
    sistent factual findings,” like those here, “are, by definition,
    clearly erroneous.” In re Sentinel Mgmt. Grp., Inc., 
    728 F.3d 660
    , 670 (7th Cir. 2013); see also United States v.
    AT&T, Inc., 
    916 F.3d 1029
    , 1033 (D.C. Cir. 2019) (citing,
    e.g., Anderson v. City of Bessemer, N.C., 
    470 U.S. 564
    , 575
    (1985)) (“A finding may be clearly erroneous when it is il-
    logical or implausible, [or] rests on internally inconsistent
    reasoning.”).
    The majority’s attempts to distinguish Kappos 2006
    from the ’405 patent fall flat. Maj. at 21–23. To be sure,
    Kappos 2006 does not “say[] the daily fingolimod dosage
    should be ‘initially’ administered.” 
    Id. at 22
    –23. But nei-
    ther does the ’405 patent. The ’405 patent uses the word
    initially to describe the length of treatment, not the dosage.
    And it is simply not correct that an issued patent is “pre-
    sumed to have a complete written description.” Maj. at 21.
    “The presumption of validity includes a presumption the
    patent complies with” the written description requirement.
    Nat’l Recovery Techs., Inc. v. Magnetic Separation Sys.,
    Inc., 
    166 F.3d 1190
    , 1195 (Fed. Cir. 1999). But it does not
    require presuming an issued patent is “complete,” which
    would mean silence presumptively supports a negative lim-
    itation in every case. That presumption is contrary to our
    long-standing precedent, which the majority recognizes
    Case: 21-1070    Document: 41      Page: 34    Filed: 01/03/2022
    10   NOVARTIS PHARMACEUTICALS     v. ACCORD HEALTHCARE INC.
    (see Maj. at 17), and a gross expansion of the presumption
    of validity.
    This specification is ambivalent as to loading doses in
    a field where, by all expert accounts, loading doses of fin-
    golimod were sometimes used to treat MS. The inventors
    do not get to claim as their invention something they did
    not disclose in the patent. There are no fact findings here
    to defer to—the patent is silent as to loading doses. The
    district court relied upon that silence: “The absence of an
    immediately preceding loading dose from the specification,
    and from the Prophetic Trial, would tell a person of skill
    that loading doses are excluded from the invention.”
    J.A. 26 ¶ 61. This is not a finding of fact; it is a misunder-
    standing of the law. An inventor cannot satisfy the written
    description requirement through silence. And when the
    majority concludes otherwise, it creates a conflict with our
    long-standing, uniformly-applied precedent including San-
    tarus, Inphi, and Nike. While the negative limitation need
    not be recited in the specification in haec verba, there must
    be something in the specification that conveys to a skilled
    artisan that the inventor intended the exclusion: disad-
    vantages, alternatives, inconsistencies, just something.
    This specification is entirely silent and ambivalent about
    loading doses. These inventors did not disclose treatment
    that must exclude a loading dose, and the district court’s
    finding to the contrary is clearly erroneous. After this case,
    negative limitations are supported by a specification that
    simply never mentions them.