IP UPDATE
Exploring the Latest in Intellectual Property Law
IP UPDATE
Exploring the Latest in Intellectual Property Law
Written Description
Subscribe to Written Description's Posts

Even Jepson Preambles Require Written Description Support

by | Mar 27, 2025 |

The US Court of Appeals for the Federal Circuit found a Jepson claim unpatentable where the specification did not provide adequate written description for the portion of the claim purporting to recite what was already well known in the prior art. In re Xencor, Inc., Case No. 24-1870 (Fed. Cir. Mar. 13, 2025) (Hughes, Stark, Schroeder, JJ.)

Xencor filed a patent application claiming a modified anti-C5 antibody treatment with certain amino acid substitutions that provide for longer serum half-lives and reduce the need for more frequent treatment. The application included:

  • A Jepson claim reciting, “[i]n a method of treating a patient by administering an anti-C5 antibody with an Fc domain, the improvement comprising” certain amino acid substitutions, wherein the modified antibody has “increased in vivo half-life.”
  • A non-Jepson claim directed to “a method of treating a patient by administering an anti-C5 antibody comprising” certain amino acid substitutions, wherein the modified antibody “has increased in vivo half-life.”

The specification provided one example of an anti-C5 antibody, 5G1.1, and three high-level examples of potential uses for anti-C5 antibodies. The examiner rejected the claims for lack of written description. Xencor unsuccessfully appealed the rejection to the Patent Trial & Appeal Board. Xencor then unsuccessfully petitioned the Board for reconsideration. Xencor appealed to the Federal Circuit, which resulted in a remand to the Board’s Appeals Review Panel (ARP).

The ARP concluded that Jepson claim preambles require written description support and that the preamble language of “treating a patient” was limiting – even without the Jepson claim format – because it gave life and meaning to the claim recitations “increased in vivo half-life” and “administering.” Because the specification did not provide a representative number of species to support the broad genus of anti-C5 antibodies, a description of conditions that can successfully be treated with an anti-C5 antibody, or even a single working example describing treatment with an anti-C5 antibody with the claimed modifications, the ARP found that the claims lacked written description and that Xencor had not shown that anti-C5 antibodies were well known. Xencor again appealed, arguing that “treating a patient” was not limiting and that Jepson preambles do not require written description support.

With respect to the preamble of the method claim, the Federal Circuit noted that Xencor agreed that the “administering” portion was limiting but nonetheless argued that “treating a patient” was not. Although a preamble can be split into limiting and non-limiting parts, the Court reasoned that the preamble here could not be neatly packaged into separate portions because the phrase “treating a patient” was directly connected through the word “by” to the phrase “administering an anti-C5 antibody,” and each phrase gave meaning to the other. The Court further explained that the entire preamble provided the raison d’être of the claimed method: When a patient is treated with the modified anti-C5 antibody, the treatment lasts longer, reducing the frequency of treatments. Accordingly, the Court agreed with the ARP that the recitation “treating a patient” was limiting.

The Federal Circuit [...]

Continue Reading



read more

Eye-Catching: Biosimilars Injunction Prevails

by | Feb 6, 2025 |

Addressing a preliminary injunction in patent litigation related to the Biologics Price Competition and Innovation Act (BPCIA), the US Court of Appeals for the Federal Circuit upheld the district court’s grant of a preliminary injunction, finding that there was a proper exercise of personal jurisdiction and that no substantial question of invalidity had been raised for the patents at issue that would prevent the injunction from issuing. Regeneron Pharmaceuticals, Inc. v. Mylan Pharmaceuticals Inc., Case No. 24-1965 (Fed. Cir. Jan. 29, 2025) (Moore, C.J.; Reyna, Taranto, JJ.)

Regeneron holds a Biologics License Application for Eylea®, a therapeutic product containing aflibercept (a VEGF antagonist used in various treatments for eye diseases). Regeneron owns multiple patents related to its Eylea® product, including a patent directed to intravitreal injections using VEGF formulations. Mylan, Samsung Bioepis (SB), and other companies filed abbreviated Biologics License Applications (aBLAs) with the US Food and Drug Administration (FDA) seeking approval to market Eylea® biosimilars. Regeneron brought suit against these parties asserting infringement of its patent and filed a motion for a preliminary injunction.

The district court granted the preliminary injunction against SB, enjoining it from offering for sale or selling the subject of its aBLA without a license from Regeneron. SB appealed, arguing that:

  • The exercise of personal jurisdiction over it was improper.
  • There was a substantial question of invalidity of the patent under either obviousness-type double patenting or lack of adequate written description.
  • There was no causal nexus established.

The Federal Circuit upheld the exercise of personal jurisdiction on SB, finding that SB had minimum contacts with the state of West Virginia. SB is headquartered in South Korea and entered into a development and commercialization agreement with Biogen for a biosimilar to Eylea®, SB15, that gives SB continuing rights and responsibilities as the agreement is implemented. The Court found that SB did not have to distribute the product itself under the agreement for it to be subject to personal jurisdiction. Further, the Court found that SB’s aBLA and internal documentation indicated an intent to distribute SB15 US-wide, which was sufficient to establish intent to distribute the product in West Virginia.

The Federal Circuit also upheld the district court’s grant of the preliminary injunction. SB invoked another patent in the same family as the asserted patent that was directed to an intravitreal injection containing a VEGF trap as the reference patent for an obviousness-type double patenting theory. The Federal Circuit upheld the district court’s findings that the stability requirement, the “glycosylated” requirement, and the “vial” limitations in the claims of the asserted patent were all patentably distinct from the reference patent. The Court found that the stability requirement recited in the asserted patent was more specific than, and not inherent within, the reference patent. The Court further agreed that the reference patent embraced both non-glycosylated and glycosylated aflibercept, not only the glycosylated aflibercept contained in the asserted patent claims.

The Federal Circuit then addressed SB’s arguments that the specification lacked sufficient written description for the claimed [...]

Continue Reading



read more

Complex or Not Written Description Is Evaluated Against Claims

by | Jan 23, 2025 |

The US Court of Appeals for the Federal Circuit reversed a district court’s ruling of invalidity for lack of written description, finding that the district court erred in its analysis of written description because patents must be evaluated based on the claims themselves, not on their construction. In re Entresto, Case No. 23-2218 (Fed. Cir. Jan. 10, 2025) (Lourie, Prost, Reyna, JJ.)

Novartis owns an approved new drug application (NDA) for a combination therapy of valsartan and sacubitril that Novartis markets under the brand name Entresto®. The term “combination therapy” is used to describe pharmaceuticals where two or more active pharmaceutical ingredients are combined in a single method of treatment. Entresto® is protected by several patents, including the patent at issue. Several generic pharmaceutical manufacturers, including MSN, filed abbreviated new drug applications (ANDAs) seeking to market generic versions of Entresto® prior to the expiration of Novartis’ patent. Novartis sued for infringement.

A unique property of Entresto® is the specific form taken by the active pharmaceutical ingredients, valsartan and sacubitril. The valsartan and sacubitril in Entresto® are present in what is known as a “complex,” meaning the two drugs are bonded together by weak, noncovalent bonds. At issue before the district court was the construction of the claim term “wherein said [valsartan and sacubitril] are administered in combination.” The inquiry focused on whether “in combination” required the valsartan and sacubitril to be chemically separated molecules (not in the form of a complex). The district court adopted Novartis’ proposal to give the term its plain and ordinary meaning because the intrinsic record was silent as to whether the molecules must be separate and not complexed. The complexed form of valsartan and sacubitril was not developed until four years after the priority date of the patent.

After the district court declined to adopt MSN’s “complexed” claim construction, MSN stipulated to infringement. The case proceeded to a bench trial on the issue of validity. The district court found the patent not invalid for obviousness, lack of enablement, and indefiniteness. However, the district court ruled that because the patent did not disclose the complexed form of valsartan and sacubitril, it was invalid for lack of written description. Novartis appealed.

Novartis argued that a complex of valsartan and sacubitril was an after-arising invention that need not have been enabled or described. The Federal Circuit agreed, finding that because the patent did not claim the complexed form of valsartan and sacubitril, those complexes need not have been described. The Court cited its “long-recognized” rule that “the invention is, for purposes of the written description inquiry, whatever is now claimed.” All that was required to meet the written description requirement was a disclosure sufficient to show that the inventors possessed a pharmaceutical composition comprising valsartan and sacubitril administered in combination. The Federal Circuit found that by considering what the claims were “construed to cover,” the district court improperly conflated the distinct issues of patentability and infringement. The Federal Circuit reversed the district court’s finding of invalidity for lack [...]

Continue Reading



read more

Later-Filed, Earlier-Expiring Patent Not an ODP Reference

by | Aug 29, 2024 |

Addressing invalidity due to obvious-type double patenting (ODP) based on later-filed-related patents, the US Court of Appeals for the Federal Circuit reversed a district court’s application of In re Cellect (Fed. Cir. 2023) and held that the later-filed, earlier-expiring continuation patents were not available as ODP references against the earlier-filed, later-expiring patent. Allergan USA, Inc. v. MSN Labs Private Ltd., Case No. 24-1061 (Fed. Cir. Aug. 13, 2024) (Lourie, Dyk, Reyna JJ.)

In 2015, the US Food and Drug Administration approved a new drug application for a drug sold by Allergan to treat the symptoms of irritable bowel syndrome. In 2019, Sun Pharma filed an abbreviated new drug application (ANDA) seeking to market a generic version of the drug. Allergan then sued Sun Pharma and MSN Labs for infringement of four patents related to the drug. One of the patents, which claims a compound of the drug, had been granted almost three years of patent term adjustment (PTA) and was followed by two more patents from continuation applications in the same patent family. The other three patents all claimed tablet forms of the drug. The claims of one of the patents recited that a glidant was optional while the claims of the other two patents did not require a glidant at all.

The US District Court for the District of Delaware held a three-day bench trial and concluded that the asserted claim of the compound patent was invalid under the ODP doctrine and that the claims of the three tablet patents were invalid for lack of written description. On the issue of ODP, the district court found Allergan’s “first-filed, first-issued” distinction “immaterial.” The district court stated that “[w]hen analyzing ODP, a court compares patent expiration dates, rather than filing or issuance dates.” Allergan appealed.

The Federal Circuit reversed on both issues. The Court held that the claims of the later-filed, earlier-expiring continuation patents were not available as ODP references against the first patent because the purpose of the ODP doctrine is to prevent patentees from obtaining a second patent to effectively extend the life of the first patent. The Federal Circuit explained that the district court misread Cellect as binding it to solely consider expiration dates in the ODP analysis. The Court explained that Cellect only controls to the extent that it requires a court to consider the later-filed patent’s expiration date (i.e., the expiration date after the addition of PTA) in its ODP analysis, not the expiration date that it would have shared with the reference patents in the absence of a PTA award. The panel majority emphasized that it does not follow that the later-filed patent must be invalidated by the earlier-filed reference patents simply because it expires later. The majority noted that “Cellect does not address, let alone resolve, any variation of the question presented here – namely, under what circumstances can a claim properly serve as an ODP reference – and therefore has little to say on the precise issue before us.”

The Federal Circuit also [...]

Continue Reading



read more

For Statutory Equivalents, Even One Means May Be Enough

by | Jun 6, 2024 |

A US Patent & Trademark Office (PTO) appeals review panel decided that a means-plus-function (M+F) claim element supported by the disclosure of only a single species is not invalid for indefiniteness or lack of written description, even if the specification lacks other disclosed statutory corresponding equivalents. Ex parte Chamberlain, Appeal No. 22-001944 (App. Review Panel, May 21, 2024) (Vidal, Dir.; Udupa, Boalick, APJs) (per curiam).

The independent claims of the patent application at issue involved methods of treating patients with “anti-C5 antibod[ies]” that include amino acid substitutions devised to increase the in vivo half-life of the antibody. Each claim involved similar preambles: “A method of treating a patient by administering an anti-C5 antibody comprising . . . .” One of the independent claims was in Jepson form, whereas the other included a M+F limitation.

Following rejections by the examiner and the applicant’s appeal to the Patent Trial & Appeal Board, the Board entered new grounds of rejection finding both claims invalid under 35 U.S.C. § 112, ¶1 (written description) and affirmed the examiner’s rejection of the claims for obviousness-type double patenting. The Board also entered a new ground of rejection finding the claim including the M+F claim element indefinite under 35 U.S.C. § 112, ¶2. Following the applicant’s appeal to the Federal Circuit, the PTO took the unusual step of petitioning the Federal Circuit to “administratively remand [the case] to the Office in order to convene an Appeals Review Panel to clarify the Office’s position on the proper analysis of ‘Jepson-format and means-plus-function claims in the field of biotechnology, and particularly in the antibody art’ and ‘to issue a revised decision.’”

On remand, the panel affirmed the Board’s determinations that written description was lacking but overturned the Board’s finding of indefiniteness for the claim including the M+F element. In doing so, the panel offered useful commentary on the invalidity standard for M+F claim elements as well as the implications that a limiting preamble may have on invalidity.

The panel found the “treating a patient” preamble recitation limiting in both claims. For the Jepson claim, the preamble was per se limiting. However, the panel went on to find that, even independent of the Jepson claim format, the “treating a patient” phrase would be limiting. Outside the Jepson context, the panel characterized the inquiry of determining whether a preamble limits the body of the claim as a highly contextual one. According to the panel, the “treating a patient” term did not merely provide “circumstances in which the method may be useful” but instead constituted “the raison d’être of the claimed method itself.” The “treating a patient” language was necessary to “give life, meaning, and vitality” to limitations in the body of the claim involving increasing the in vivo half-life of the antibodies and administering the antibodies.

Having determined that the “treating a patient” recitation was limiting, the panel found that the limitation was overbroad compared to the scope of the patent’s disclosure, and thus the Jepson format claim lacked adequate written description. Read in light of [...]

Continue Reading



read more

Consider Invention When Assessing Support for Claimed Range

by | Feb 29, 2024 |

The US Court of Appeals for the Federal Circuit affirmed in part and vacated in part a Patent Trial & Appeal Board finding that the claims at issue were either invalid under 35 U.S.C. §112 as unsupported by written description or obvious under 35 U.S.C. §103. RAI Strategic Holdings, Inc. v. Philip Morris Products S.A., Case No. 22-1862 (Fed. Cir. Feb. 9, 2024) (Chen, Stoll, Cunningham, JJ.)

RAI owns a patent with claims directed to “electrically powered smoking devices that provide an inhalable vapor by heating tobacco or other substances without significant combustion.” Philip Morris challenged the patent in a post-grant review (PGR).

The Board issued a final written decision concluding that two dependent claims, which recited limitations requiring a heating member with “a length of about 75% to about 85% of a length of the disposable aerosol forming substance,” lacked § 112 written description support. The specification disclosed ranges of 75% – 125%, 80% – 120%, 85% – 115% and 90% – 110%. The Board explained that written description support was lacking because “the claimed range is different from and substantially narrower than the specific ranges disclosed in the specification.”

The Board found that the remaining claims were unpatentable as obvious based on a combination of prior art references where the heater found in one reference, Robinson, was replaced with the heater from another, Greim. Robinson explained that its heating element could be altered and acknowledged design choices, thus inviting skilled artisans to select an alternate appropriate heating element. Greim disclosed certain advantages to its heater. Thus, the Board found that a skilled artisan would have been motivated to replace Robinson’s heater with that of Greim, rendering the claims obvious. RAI appealed.

Citing its expert, RAI argued that the ranges disclosed in the specification all centered around 100%, so that a person of ordinary skill in the art (POSITA) would not “conclude that the inventors possessed a range that went no higher than 85%[.]” The Federal Circuit began by summarizing a line of numerical range cases, including:

  • In re Wertheim (CCPA 1976), which found that a described range of 25% – 60%, with examples of 36% and 50%, supported a claim directed to a range of 35% – 60%.
  • In re Blaser (CCPA 1977), which found that a described range of 60° – 200° C supported a claim reciting a range of 80° – 200° C.
  • Kolmes v. World Fibers Corp. (Fed. Cir. 1997), which found that a described range of 4 – 12 turns per inch, and preference for 8 turns per inch, supported claims directed to 8 – 12 turns per inch.
  • In re Baird (CCPA 1965), which found that a relatively unexplained disclosure of 32 – 176° F did not support claims directed to a range from 40° to “at least as low as” 60° F.
  • Indivior UK v. Dr. Reddy’s Laboratories (Fed. Cir. 2021), which found that:
    • Disclosure of ranges of at least 25%, at least 50% and “any” value [...]

      Continue Reading


read more

Holy Pulmonary Hypertension, Batman: Method of Treatment Not Constrained by Safety and Efficacy

by | Aug 3, 2023 |

The US Court of Appeals for the Federal Circuit affirmed a district court’s holding that the asserted method of treatment patent was valid and infringed because safety and efficacy are not patent concerns. The Federal Circuit also affirmed the district court’s holding that certain claims of the product-by-process patent were invalid because the claimed product was in the prior art, regardless of the process by which it was made. United Therapeutics Corporation v. Liquidia Technologies, Inc., Case Nos. 22-2217; 23-1021 (Fed. Cir. July 24, 2023) (Lourie, Dyk, Stoll, JJ.)

United Therapeutics is the maker of Tyvaso®, a treprostinil formulation approved for treating pulmonary hypertension. United Therapeutics asserted two patents covering Tyvaso® against Liquidia’s § 505(b)(2) new drug application (NDA) on Yutrepia™. One patent was a method of treatment patent claiming to treat pulmonary hypertension by administering a “therapeutically effective” dose of a treprostinil formulation, and the other was a product-by-process patent claiming a treprostinil composition with lowered levels of impurities made by a specific salt formation process.

The district court found that United Therapeutics showed that a single administration of treprostinil improves a patient’s hemodynamics, establishing that administration of Liquidia’s Yutrepia, comprising treprostinil, would directly infringe the method of treatment claims. The district court also concluded that even though Yutrepia’s label did not provide hemodynamic data, the label’s instructions would inevitably lead to the administration of a therapeutically effective single event dose. The court thus concluded that Liquidia would induce infringement of the method of treatment claims.

The district court further found that the asserted claims were not invalid for lack of enablement or written description. The court reasoned that a skilled artisan would not need to engage in undue experimentation to practice the full scope of the claimed treatment of pulmonary hypertension, despite potential safety concerns in treating certain patients, since the claims did not require safety and efficacy. The court found that the claims were not invalid for lack of written description, finding that a skilled artisan would, based on the specification, understand that treprostinil would effectively vasodilate the pulmonary vasculature, improve hemodynamics and treat a patient’s elevated pulmonary blood pressure.

Liquidia appealed on five issues: claim construction of the term “treating pulmonary hypertension,” enablement, written description, induced infringement and infringement of the product by process claims. United Therapeutics cross-appealed on anticipation of the product by process claims and non-infringement of those claims.

First, regarding the construction of “treating pulmonary hypertension,” the Federal Circuit affirmed that the term encompassed all recognized groups of pulmonary hypertension but noted that the claim language “treating pulmonary hypertension” did not import any additional efficacy limitations or safety limitations, even those in a group that would not benefit from the treatment. The Court declined to read any safety or efficacy requirements into the claims, explaining that absent incorporation into the claims, the safety and efficacy of a claimed treatment are the purview of the US Food & Drug Administration (FDA), not patent law.

Regarding enablement and written description, Liquidia argued that the method [...]

Continue Reading



read more

First Rule of the PTAB? Play by the Rules

by | Jun 22, 2023 |

The US Court of Appeals for the Federal Circuit affirmed two Patent Trial & Appeal Board decisions holding the challenged claims unpatentable as obvious, even though the Board declined to consider evidence of antedating and found that the claims lacked written description support. Parus Holdings, Inc. v. Google LLC, Case Nos. 22-1269; -1270 (Fed. Cir. June 12, 2023) (Lourie, Bryson, Reyna, JJ.)

Parus Holdings owns two patents related to an interactive voice system to request information from a voice web browser. Google (among others) petitioned for inter partes review (IPR) of the patents.

During the IPR proceedings, the Board found that a publication (Kovatch) was prior art to the challenged patents. In reaching that decision, the Board declined to consider Parus’s arguments and evidence of an earlier conception and reduction to practice because they were only presented via incorporation by reference in violation of 37 C.F.R. § 42.6(a)(3). The Board ruled that Parus failed to meet its burden of production on antedating.

The Board also found that the publication of the application to which Parus’s challenged patents claimed priority (Kurganov-262) was prior art because the common specification failed to provide written description support for the challenged claims. Parus appealed the Board’s decision, raising two main arguments.

First, Parus contended that the Board erred when it declined to consider Parus’s arguments and evidence on antedating. Parus argued that § 42.6(a)(3)’s prohibition on incorporation by reference did not warrant the Board’s decision because Parus, as patent owner, need not have submitted a response at all. Parus also argued that the Federal Circuit’s 2017 decision in Aqua Products mandates that the Board consider all record evidence, regardless of the manner of presentation. The Federal Circuit rejected Parus’s arguments in turn.

Regarding Parus’s violation of the incorporation by reference rule, the Federal Circuit explained that Parus had assumed an affirmative burden of production when it chose to submit a response to antedate Kovatch. Along with that burden came other responsibilities, such as complying with the US Patent & Trademark Office’s (PTO) rules and regulations, including § 42.6(a)(3). The Court further explained that this burden of production could not be met without some combination of citing evidence with specificity and explaining the significance of the cited material. Parus did neither.

The Federal Circuit also rejected Parus’s argument that the Board is required by law to review all evidence in the record. The Court clarified that, while its Aqua Products holding requires the Board to decide all issues properly before it, nothing in Aqua Products requires the Board to review evidence or issues not introduced or introduced in violation of the Board’s rules. As the Court noted, “[t]he burden of production cannot be met simply by throwing mountains of evidence at the Board without explanation or identification of the relevant portions of that evidence. One cannot reasonably expect the Board to sift through hundreds of documents, thousands of pages, to find the relevant facts.”

Parus also argued that the Board exceeded its statutory authority under 35 U.S.C. [...]

Continue Reading



read more

Hanging Patentability on Written Description Cannot Be Truss-ted

by | May 4, 2023 |

The US Court of Appeals for the Federal Circuit upheld a Patent Trial & Appeal Board finding that the claims of a patent for a truss hanger were invalid for lack of written description because they claimed an undisclosed range despite the predictable nature of the technology. Columbia Insurance Company v. Simpson Strong-Tie Company Inc., Case Nos. 21-2145; -2157 (Fed. Cir. Mar. 31, 2023) (Prost, Hughes, JJ.) (Moore, C.J., dissenting) (non-precedential).

Truss hangers secure support beams to wall frames in buildings. These hangers normally accommodate layers of fire-resistant sheathing by cutting out the sheathing that overlaps with the hanger, but this can reduce fire resistance. Columbia owns a patent claiming a truss hanger that extends through the sheathing and does not decrease fire resistance. The extension for the sheathing, illustrated below, must be “sized large enough to permit two layers of ⅝ inch thick sheathing to be received between the rear edge plane and the back flange plane, but too small to permit three layers of ⅝ inch thick sheathing to be received.”

Simpson petitioned for a post-grant review of the patent at the Board. That proceeding resulted in a mixed decision. The Board found in favor of Simpson that certain original claims and certain substitute claims of the patent were unpatentable for lack of written description and that certain claims were obvious over the prior art. However, it found in favor of Columbia with regard to one claim. Both parties appealed.

The Federal Circuit affirmed the Board’s findings regarding written description. The claimed extension portion covered a range of extension sizes between the upper limit (three layers of five-eighths-inch-thick sheathing) and lower limit (two layers of five-eighths-inch-thick sheathing). The Court affirmed the Board’s finding that nothing in the specification covered the claimed upper limit. Columbia argued that a skilled artisan would read the claims to cover exactly two layers of five-eighths-inch-thick sheathing, but the Court found that this claim construction argument was forfeited because it was raised for the first time on appeal and, even if it weren’t, it was incorrect because it was akin to rewriting the claims.

The Federal Circuit also affirmed the Board’s finding that certain claims were obvious, concluding that the Board’s determination was supported by substantial evidence. The Court rejected Columbia’s argument that the Board’s claim construction violated the Administrative Procedure Act because the construction adopted by the Board was similar enough to Simpson’s proposed construction and not raised sua sponte.

Finally, the Federal Circuit affirmed the Board’s finding that the claim on which Simpson appealed was not indefinite because the term “large enough to permit the drywall to be received” informs a skilled artisan with reasonable certainty that the scope of this claim includes any extension portion sized larger than the smallest commonly known sheathing size. The Court also found that the claim was not obvious because the Board correctly interpreted the claim language [...]

Continue Reading



read more

A Maze-Like Path and Laundry List Don’t Provide Written Description

by | Mar 16, 2023 |

The US Court of Appeals for the Federal Circuit affirmed a Patent Trial & Appeal Board (Board) decision that there was insufficient written description in the asserted priority applications to support a genus claim because of a lack of ipsis verbis disclosure and insufficient blaze marks. The Court concluded that the priority applications did not support an early priority date. Regents of the University of Minnesota v. Gilead Sciences, Inc., Case No. 21-2168 (Fed. Cir. March 6, 2023) (Lourie, Dyk, Stoll, JJ.)

Gilead filed a petition for inter partes review (IPR) challenging Minnesota’s patent directed to phosphoramidate prodrugs preventing virus reproduction or cancerous tumor growth. Gilead’s US Food & Drug Administration-approved drug, sofosbuvir, is marketed by Gilead to treat chronic hepatitis C infections and falls within claim 1 of the patent.

The 2014 application that issued as the challenged patent claimed priority to four applications. In the IPR, Gilead argued that the claims were anticipated by a Gilead-owned patent publication (Sofia). The publications used in the decision are as follows:

NP3 and NP2 have the same disclosure. NP2 and P1 contain similar disclosures, which the Board called NP2-P1. The broader claim in NP2-P1 has a relationship of genus to the narrower subgenus claims in the patent at issue. There was no dispute that Sofia disclosed every limitation of each challenged claim. The Board held that NP2-P1 failed to provide a sufficient written description to support the asserted priority date of the challenged claims, which were therefore found to be anticipated by Sofia. Minnesota appealed.

Minnesota argued the following to the Federal Circuit:

  • The Board erred in holding that the NP2-P1 applications have insufficient written description.
  • The Board ran afoul of Administrative Procedure Act (APA) requirements.
  • Minnesota is a sovereign state entity immune from IPR.

35 U.S.C. § 120 sets forth requirements for a patent application to benefit from a filing date of an earlier application. Minnesota asserted that the NP2-P1 priority applications literally described or provided blaze marks to the challenged subgenus claims. The Federal Circuit disagreed, explaining that written description for a genus claim of chemical compounds raises “particular issues,” requiring a description of the outer limits of the genus and either a representative number of members or structural features common to the members of the genus. The Court found that the asserted priority applications (NP2-P1) did not provide such description and the challenged claims were not entitled to the filing dates of those applications.

The Federal Circuit found that the asserted priority applications did not provide ipsis verbis disclosure of the challenged subgenus claim. The Court quoted an oft-noted saying associated with Yogi Berra, a catcher for the New York Yankees some 50 years ago, about a notable failure to provide direction: “when one comes to a fork in the road, take it.” The Court also cited its 1996 decision in Fujikawa [...]

Continue Reading



read more

BLOG EDITORS

Paul Devinsky

Amol Parikh

Jodi Benassi

STAY CONNECTED

Subscribe

TOPICS

ARCHIVES

Legal Notices  |  Privacy & Cookies Policy

Attorney Advertising © 2025 McDermott Will & Emery

Contact Us: info@mwe.com

Attorney Advertising ©2020 McDermott Will & Emery