All posts by Holman

After Granting Certiorari In Enablement Case, Supreme Court Declines Opportunity To Address Written Description

by Chris Holman

As reported in posts by Dennis and Jason, the Supreme Court recently granted certiorari in Amgen v. Sanofi, marking the first time that the Court has taken up patent law’s enablement requirement since enactment of the Patent Act of 1952. The claims at issue are directed to a genus of functionally-defined molecules having therapeutic utility, i.e., monoclonal antibodies defined in terms of binding specificity. For the sake of brevity, I will refer to claims of this type as “chemical genus claims.”

A few days later, on November 7, the Supreme Court denied certiorari in Juno v. Kite, a case challenging the Federal Circuit’s interpretation of the written description requirement. The claims struck down for lack of adequate written description in Juno are strikingly similar to the claims that were invalidated under the enablement requirement in Amgen, being directed towards nucleic acids encoding chimeric T cell receptors (for use in Car T-cell therapy), comprising, inter alia, a functionally defined “binding element,” as exemplified by a single-chain antibody variable fragment (‘‘scFv’’).

The scope afforded to chemical genus claims under 35 USC § 112(a)’s enablement and written description requirements has been hot topic recently (at least in certain quarters). Professors Lemley, Seymore, and Karshtedt (it is so sad that he is no longer with us) published an article in 2020 entitled The Death of the Genus Claim, which asserts that “the law has changed dramatically in the last thirty years, to the point where it is nearly impossible to maintain a valid genus claim.” Amgen’s successful petition for certiorari relies heavily on Death, and its authors filed an amici curiae brief in support of Amgen’s petition.

While Death clearly raises some valid concerns regarding the challenges inventors face in trying to secure effective patent scope for inventions of this type, in my view it is an overstatement to say that chemical genus claims are “dead.” I responded to Death in a two-part article arguing, for example, that the case law identified in Death provides scant support for its assertion that the standard for compliance with the enablement and written description requirements has become significantly more stringent in recent years. Christopher M. Holman, Is the Chemical Genus Claim Really “Dead” at the Federal Circuit?: Part II, 41 Biotechnology Law Report 58 (2022); Christopher M. Holman, Is the Chemical Genus Claim Really “Dead” at the Federal Circuit?: Part I, 41 Biotechnology Law Report 4 (2022).

I also point out that relatively broad chemical genus claims continue to survive § 112(a) challenges in the district courts and at the Federal Circuit.  See, for example, Ajinomoto Co. v. Int’l Trade Comm’n, 932 F.3d 1342 (Fed. Cir. 2019); Bayer Healthcare LLC v. Baxalta Inc., 989 F.3d 964 (Fed. Cir. 2021); Plexxikon Inc. v. Novartis Pharmaceuticals Corp., Case No. 17-cv-04405-HSG, Document 565, July 22,2021 (N.D. Cal.).

Section 112(a)’s enablement and written description requirements, sometimes referred to as the “adequate disclosure requirements,” constitute U. S. patent law’s primary non-prior art-based limitations on claim scope. Although Supreme Court has in the past indicated that it views the patent eligibility doctrine as playing an important role in preventing patent claims from broadly “preempting” abstract ideas and natural phenomena, more recently the Court’s patent eligibility decisions have focused on the sufficiency of “inventive concept,” as opposed to claim breadth per se.  Absent such limitations, under a regime in which claim scope would only be limited by the prior art, an inventor could potentially secure patent claims encompassing huge swaths of yet-to-be invented technologies.

Hypothetically, for example, the inventor of the first practical method for communicating at a distance using electricity, e.g., the telegraph, might have ended up with a patent claim encompassing all means of communicating at a distance using electricity, e.g., the internet. The inventor of a rudimentary, barely functional electric light bulb could, assuming it was the first lightbulb, potentially have obtained a patent claim encompassing all lightbulbs, including far superior lightbulbs produced by subsequent inventors. While I have simplified the facts quite a bit, the gist of these examples have been the subject of actual Supreme Court decisions. O’Reilly v. Morse and Consol. Elec. Light Co. v. McKeesport Light Co..  Not surprisingly, in both cases the Supreme Court struck down the patent claims as overly broad, invoking what we would today refer to as the enablement requirement.

More pertinent to the facts of Amgen v. Sanofi, the inventor of the first antibody capable of recognizing a particular antigen could potentially obtain a patent encompassing all antibodies capable of recognizing that antigen. For example, an inventor who has succeeded in producing a mouse monoclonal antibody that binds to a particular human protein (useless as a human therapeutic) could in principle obtain a patent claim encompassing all monoclonal antibodies that bind to that particular human protein, even a fully humanized antibody that functions as a safe and effective biologic drug, e.g., AbbVie’s blockbuster Humira, or the accused product in Amgen, Praluent.  Again, the gist of this example comes from an actual Federal Circuit decision, Noelle v. Lederman, wherein the claims at issue were struck down under the written description requirement.

The Federal Circuit has invoked both the written description and enablement requirements as doctrinal tools for policing claim scope. Although as a formal matter the written description requirement focuses on whether the inventor has demonstrated “possession” of the full scope of the claim, while the enablement requirement asks whether the scope of the claim is “commensurate” with the scope of disclosure, as a practical matter the two requirements have been applied in a manner that is largely redundant, albeit with a few distinctions of arguable significance discussed later in this post. In my article responding to Death, for example, I point out that the Ariad factors that the Federal Circuit has identified as relevant to assessing compliance with the written description requirement are, in substance, virtually identical to the Wands factors used in the enablement inquiry. If anything, the written description requirement has been seen as the more stringent of the two, particularly in the context of biotechnology – the written description requirement has often been referred to as a  “super-enablement” requirement.

And in fact, prior to Amgen, the Federal Circuit has tended to invoke the written description requirement, rather than the enablement requirement, in striking down monoclonal antibody genus claims. See, for example, Noelle v. Lederman, 355 F.3d 1343, 1349 (Fed. Cir. 2004)(disclosure of mouse monoclonal antibody specific for mouse antigen (CD40CR) did not provide adequate written description for claim encompassing any monoclonal antibody capable of binding the human analog of the CD40CR antigen); Centocor Ortho Biotech v. Abbott Laboratories, 636 F.3d 1341(Fed. Cir. 2011)(disclosure of previously characterized antigen (human TNF-alpha) and mouse antibodies to the antigen did not provide adequate written description for claim encompassing fully human monoclonal antibodies capable of binding to a specific neutralizing epitope of the antigen); AbbVie Deutschland GmbH & Co., KG v. Janssen Biotech, Inc., 759 F.3d 1285 (Fed. Cir. 2014)(disclosure of about 300 antibodies falling within the scope of the claim did not provide adequate written description for a claim reciting neutralizing human antibodies capable of specifically binding human interleukin-12 (IL-12)).

Of course, given the redundancy of the doctrines, a claim struck down as overly broad for lack of enablement is highly likely to be invalid for lack of adequate written description, and vice versa. In Amgen, for example, the jury found Amgen’s claims not invalid under the enablement and written description requirements, but on a motion for JMOL the district court overruled the jury and found that, as a matter of law, the claims are invalid under both the enablement and written description requirements. In Amgen, the Federal Circuit decided the issue based on a failure to comply with the written description requirement, rendering the enablement issue moot, but in the past the Federal Circuit has been more inclined to find claims of this type invalid for failure to comply with the written description requirement.  See the examples provided above, as well as the Juno decision.

Thus, one of the big elephants in the room with respect to the grant of certiorari in Amgen is that the question for review appears to focus solely on the enablement requirement. Even if the Supreme Court lowers the bar for compliance with the enablement requirement, the ruling would presumably have no direct impact on the written description requirement, which has conventionally been thought of as imposing an even higher bar for the sort of claim at issue in the case, e.g., functionally defined chemical genus claims.

Sanofi raised this point in its Opposition brief, arguing that any ruling by the Supreme Court would not be dispositive of the case because, if the Supreme Court overturns the enablement verdict, the Federal Circuit would likely still find the claims invalid for lack of adequate written description. Sanofi points out that Amgen’s own amici, i.e., Professors Lemley, Seymore and Karstedt, concluded in Death that the Federal Circuit had “strongly suggested” that the claims were not only invalid under the enablement requirement, but also the written description requirement.

Indeed, the Federal Circuit has on occasion explicitly noted that a claim’s compliance with the written description and enablement requirements generally rise and fall together. For example, in Idenix v. Gilead, a recent case involving claims analogous to those at issue in Amgen, the jury also found the claims to be not invalid under the enablement and written description requirements. The district court overturned the jury verdict with respect to enablement, but denied a motion for JMOL with respect to written description. On appeal, the Federal Circuit affirmed the district court’s holding that the claims were invalid for lack of enablement, but reversed its denial of JMOL for failure to meet the written description requirement, finding the claims invalid under both doctrines.

Under the Federal Circuit’s current interpretation of the written description and enablement requirements, I think it would be highly unusual for the court to find claims of the type at issue in Amgen invalid for lack of enablement but not for lack of adequate written description. In fact, when the district court decision in Idenix v. Gilead initially came out, finding the claims invalid under the enablement requirement but not under the written description requirement, I thought it was so striking that I wrote an article about it.   Christopher M. Holman, Enablement Invoked as a ‘‘Super-Written Description Requirement’’ to Overturn $2.5 Billion Jury Verdict, 37 Biotechnology Law Report 63 (2018). So I was not at all surprised when the Federal Circuit reversed and explicitly found the claims invalid under both the enablement and written description requirements, even though the Federal Circuit could have chosen not to address the written description issue as moot in light of the enablement ruling, as it did in Amgen.

In retrospect, I wonder if it might have been better for the Supreme Court to take up the issue of adequate disclosure in a case like Idenix, where the Federal Circuit explicitly addressed both the enablement and written description requirements in the context of the same chemical genus claims. As Jason intimated in his blog post, while it is relatively easy to point out the shortcomings in the Federal Circuit’s current § 112(a) jurisprudence, it is much harder to come up with an effective alternative. I have to think that it will be particularly difficult for the Supreme Court to make a positive contribution to the law of adequate disclosure without also taking into account the written description requirement.

Although the written description requirement has long been used to police the claiming of new matter, it only took on the role of policing claim scope as what is in essence an alternate enablement requirement in 1997 when the Federal Circuit decided UC Regents v. Eli Lily, creating what I refer to as the “Lilly written description requirement” (so as to distinguish it from the “traditional written description requirement” used prevent the claiming of new matter). Early on, the Lilly written description requirement seemed to impose a much higher threshold than enablement, particular for biotechnology inventions, hence its characterization as a “super-enablement requirement.” But it seems to me that at this point in time the standards for compliance with the written description and enablement requirements have become for the most part indistinguishable, as illustrated by the redundancy of the Ariad and Wands factors, and the paucity (or, to my knowledge, the absence) of any judicial decisions (upheld on appeal) explicitly finding a claim invalid under the Lilly written description requirement but not invalid for lack of enablement, or vice versa.

Nonetheless, Federal Circuit precedent has carved out some clear differences between the written description requirement and enablement, although as a practical matter it is not clear to me how significant those differences are.  For example, the Federal Circuit treats the written description requirement as a question of fact, and the enablement requirement as a question of law based on underlying factual findings.  In its petition for certiorari, Amgen also asked the Court to rule that enablement, like written description, is a question of fact, but the Court declined to take up that question. In principle, a decision by a jury (or judge in a bench trial) should be afforded more deference with respect to a question of fact, which might explain why in Amgen and Idenix the district courts overturned the juries’ enablement decisions, but not their written description decisions. However, it seems to me that when case reaches the Federal Circuit the formal distinction between question of fact and “question of law based on underlying factual findings” has little practical effect.  See, for example, Centocor Ortho Biotech v. Abbott Laboratories, 636 F.3d 1341(Fed. Cir. 2011)(overturning jury decision finding claim encompassing fully human monoclonal antibodies not invalid for failure to comply with the written description requirement).

Another difference between the two doctrines has to do with the admissibility of evidence.  In the Federal Circuit’s first decision in Amgen v. Sanofi (the grant of certiorari is with respect to the Federal Circuit second decision in the case), the court held that the district court had committed legal error by improperly excluding post-priority date evidence of antibodies falling within the scope of the claim, including the accused product (Praluent). The district court based its decision to exclude the evidence on a 1977 decision of the Court of Customs and Patent Appeals, In re Hogan, which the Federal Circuit has interpreted as prohibiting, in the context of the enablement inquiry, admission of “post-priority-date evidence proffered to illuminate the post-priority-date state of the art.”  Without questioning the continuing vitality of Hogan, the Federal Circuit held that, in the context of the written description inquiry, post-priority-date evidence is admissible to show that a patent fails to disclose a representative number of species, explaining that Hogan is silent with respect to evidence of this type. Thus, it seems that under some circumstances post-priority-date evidence illustrating the structural and functional breadth of a chemical genus claim could be admissible for purposes of a written description challenge but not a challenge for lack of enablement.

When Does Disclosure of a Chemical Genus Anticipate a Species?

by Chris Holman

Mylan Pharms. Inc. v. Merck Sharp & Dohme Corp., 2022 WL 4541687 (Fed. Cir. Sept. 29, 2022)

As a general rule of thumb, the prior art disclosure of a chemical species anticipates (and thus renders unpatentable) a chemical genus encompassing that species. The prior art disclosure of a chemical genus, on the other hand, generally does not anticipate a species falling within the scope of the genus – except when it does.  In re Petering, 301 F.2d 681 (C.C.P.A. 1962), decided by the Court of Customs and Patent Appeals (the predecessor of the Federal Circuit) in 1962, provides an example in which the court holds that prior art disclosing a genus of 20 chemical compounds anticipated a species falling within that genus. The Petering court explained that the prior art may be deemed to disclose each member of a genus when, reading the reference, a person of ordinary skill can “at once envisage each member of this limited class.”

Mylan v. Merck provides an example going the other way, with the Federal Circuit affirming a Patent Trial and Appeal Board decision finding that the prior art disclosure of a genus comprising 957 predicted salts did not anticipate the following claim, which recites one of those salts.

  1. A dihydrogenphosphate salt of a 4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro [1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine of Formula I:

or a hydrate thereof.

The claimed salt is sitagliptin dihydrogenphosphate (“sitagliptin DHP”), a dipeptidyl peptidase-IV (“DP-IV”) inhibitor and the active ingredient in JANUVIA, which is marketed by Merck for the treatment of non-insulin-dependent (i.e., Type 2) diabetes.  Mylan petitioned for inter partes review (IPR) of a number of patent claims of U.S. Patent 7,326,708 (the “’708 patent”), including the independent claim presented above, as part of its bid to bring a generic version of JANUVIA to market prior to expiration of the patent. Mylan argued that the challenged claims were anticipated and/or rendered obvious by the disclosure of the genus of 957 salts in an earlier Merck-owned U.S. patent and its equivalent International Patent Publication (referred to collectively as “Edmondson”).

In particular, Mylan argued that under In re Petering Edmondson’s disclosure of the genus anticipated the challenged claims because a skilled artisan reading Edmondson would “at once envisage” the sitagliptin DHP salt. But the Board rejected this argument, finding that none of the challenged claims were anticipated by Edmondson. The Federal Circuit affirmed, finding that while In re Petering does stand for the proposition that a skilled artisan may “at once envisage each member of [a] limited class,” the “key term” in this statement is the word “limited.”  The court found that the genus of 957 salts disclosed in Edmondson is a far cry from the 20 compounds “envisaged” by the narrow genus in Petering.

The Federal Circuit went on to explain:

We cannot provide a specific number defining a “limited class.” It depends on the “class.” But we agree with Merck and hold that the Board did not err in finding that a class of 957 predicted salts[, as disclosed in Edmondson,] is insufficient to meet the “at once envisage” standard set forth in Petering.

The manner in which Edmondson discloses the genus probably had some bearing on the outcome. Edmondson does not explicitly define a genus of 957 salts. Instead, Edmondson discloses a list of 33 compounds, one of which was sitagliptin.  It also discloses eight “preferred salts,” one of which was phosphate, the salt used in sitagliptin DHP.  The product of multiplying 33 x 8 is 264, so there are at least 264 possible combinations of the 33 chemical compounds with the eight salts. But there are also possible differences in stoichiometry, i.e., the ratio of the salt’s ions. For example, the stoichiometry of the claimed sitagliptin DHP is 1:1, i.e., a 1-to-1 ratio of sitagliptin to phosphate.  However, other stoichiometry’s are possible.  For example, Merck was also able to prepare sitagliptin phosphates having stoichiometries of 3:2 and 2:1. Taking into account the various possible stoichiometries, the court accepted Merck’s representation that the 33 compounds could potentially be formulated into a total of 957 different salt forms using the eight preferred salts.

Of course, the fact that Edmondson does not anticipate the claims does not necessarily mean that it would not render them obvious, particularly in combination with other prior art references. In this case, however, Edmondson could not be used as a prior art reference for purposes of obviousness with respect to a number of the claims at issue in the IPR, including Claim 1. In a nutshell, the reason for this was that under pre-AIA 35 U.S.C. 103(c)(1) Edmondson could not be used as 102(e)/103 prior art because Edmondson and the challenged patent were both owned by Merck, and Merck was able to antedate Edmondson as a 102(a)/103 reference with respect to Claim 1 and some of the other claims at issue.

Merck was not able to antedate Edmondson with respect to some of the other challenged claims, including Claim 4, which depends from Claim 1 and recites a crystalline monohydrate form of the (R)-enantiomer of sitagliptin DHP.  I think it is safe to assume that Claim 4 corresponds to the proposed generic product, given that in Canadian proceedings (discussed below) Mylan stipulated that its product would infringe the Canadian equivalent of Claim 4. The Board addressed the merits of Mylan’s assertion that Edmondson (in combination with other prior art) rendered Claim 4 obvious, and concluded that it did not. The Federal Circuit affirmed this conclusion.

This past April, a Canadian court issued a decision finding the Canadian equivalent of Claim 4 not invalid for obviousness and/or insufficiency (i.e., lack of enablement).  Significantly, the Canadian Court found that “[t]he evidence indicates that the [skilled artisan] would not have any specific motivation arising from [Edmondson] to focus on the particular crystalline form of a salt of sitagliptin over the other compounds disclosed within [Edmondson].”

Last month, Merck announced that the U.S. District Court for the Northern District of West Virginia had found the ‘708 patent not invalid and infringed in a Hatch-Waxman infringement suit brought against Mylan (which is now a part of Viatris).  I tried to take a look at that decision, but found that it had been filed under seal.  The case is being appealed to the Federal Circuit, and it will be interesting to see what happens if that appeal results in a decision.  Bear in mind that in patent infringement litigation the accused infringer (e.g., Mylan) is able to rely on prior art (e.g., public use or on-sale events) and grounds for invalidation (e.g., obviousness-type double patenting or lack of enablement) that are not available in IPR proceedings.

CareDx v. Natera: Some Further Thoughts on the Patent Eligibility of Molecular Diagnostics

By Chris Holman

A couple days ago Dennis posted a nice review of the Federal Circuit’s recent decision in CareDx v. Natera, in which he emphasized the fact that the court characterized a number of boilerplate statements in the patent document as “admissions” that the various DNA analysis technologies recited in the claims, e.g., next-generation sequencing (“NGS”) and digital PCR, were “conventional” for purposes of step two of the Alice/Mayo framework. I decided to write this follow-up post to explain why, in my view, these “admissions” in the patent document did not affect the outcome in the case, and that these claims were doomed irrespective of the patent’s characterization of the technologies.

The reason these claims were deemed patent ineligible, in my view, is that they are directed towards a molecular diagnostic method, and, as Judge Moore bemoaned in her dissent from the Federal Circuit’s denial of en banc rehearing of Athena Diagnostics v. Mayo, 927 F.3d 1333 (Fed. Cir. 2019), the Federal Circuit’s current interpretation of the Supreme Court’s decision in Mayo v. Prometheus has “resulted in a per se rule that excludes all diagnostics from eligibility.”  She notes that ‘[s]ince Mayo, we have held every single diagnostic claim in every case before us ineligible.” As such, the outcome in CareDx was, in my opinion, preordained. In fact, it would have been quite unexpected if the Federal Circuit had upheld the eligibility of the claims, given that in Athena Diagnostics all 12 of the judges that heard the case appeared to agree with Judge Moore’s assessment of the current state of affairs at the Federal Circuit regarding the eligibility of diagnostic claims of this type.

Athena Diagnostics is a very interesting decision for those of us concerned about the patent eligibility of molecular diagnostics. It resulted in eight separate opinions, in which all 12 of the judges who decided the case joined, in various combinations. Interestingly, as Judge Moore pointed out, ‘”[n]one of [her] colleagues defend[ed] the conclusion that claims to diagnostic kits and diagnostic techniques, like those at issue, should be ineligible.” In fact, my reading of the decisions is that all of the judges agreed that molecular diagnostics should generally be eligible for patent protection, and that the fact that they currently are not is a significant cause for concern.

There is a split of the court, however, with respect to whether the Federal Circuit has the ability to address the problem without an intervention by the Supreme Court or Congress. A seven judge majority (Lourie, Reyna, Chen, Hughes, Prost, Taranto, and Dyk) believes that the court’s hands are tied, and that Mayo dictates that diagnostic methods are patent ineligible. Judge Lourie, for example, wrote that the court could “accomplish little in [rehearing this case], as we are bound by the Supreme Court’s decision in Mayo.”  Judge Hughes “agree[d] that the language in Mayo, as later reinforced in Alice, forecloses this court from adopting an approach or reaching a result different from the panel majority’s.”

In light of this interpretation of Supreme Court precedent, these judges thought it would be futile to take up the case en banc. For example, Judge Hughes wrote that, while he “agree[d] that the bottom line for diagnostics patents is problematic[,] this is not a problem that we can solve. As an inferior appellate court, we are bound by the Supreme Court.”

The five dissenting judges (Moore, O’Malley, Wallach, Stoll, and Newman), on the other hand, expressed the view that, in fact, Mayo had not rendered all molecular diagnostics patent ineligible per se, and that the Federal Circuit had erred in interpreting Mayo in this restrictive manner. Judge Newman, for example, found the “majority’s position [to be] a flawed interpretation of the Court’s decision in [Mayo].  The Court did not hold that methods of diagnosis are subject to unique patent-eligibility rules. We have mistakenly enlarged the Court’s holding, in substance and in application.”  These five judges would have reheard the case en banc, allowing the Federal Circuit an opportunity to correct this perceived error, and opening up the door for the patenting of at least some molecular diagnostics.

Notably, two of the judges that decided CareDx, Lourie and Hughes, were part of the Athena Diagnostics majority that interpreted Mayo as requiring a finding of patent ineligibility for diagnostic claims of this type. The third judge on the CareDx panel, Judge Bryson, was a senior judge at the time Athena Diagnostics was decided, and did not participate in that decision.

In CareDx, the patent owner tried unsuccessfully to convince the court that the DNA analysis techniques specifically recited in the claims were “unconventional” enough to avoid the strictures of Mayo. While implicitly acknowledging that techniques such as PCR and DNA sequencing are conventional, CareDx basically argued that digital PCR and next-generation sequencing were sufficiently cutting edge at the time of the purported invention as to be not “conventional” for purposes of the Mayo two-part framework. But these techniques were apparently known to those of skill in the art at the time, and under the Federal Circuit’s current interpretation of Mayo I think the court would have found the use of any known method of DNA analysis to be lacking in the “inventiveness” required to meet the standard. While the “admissions” in the patent document provided a convenient route for the court to conclude that the methods were conventional, I think it would have arrived at the same conclusion regardless of any statements made in the patent, given that these techniques were presumably not novel at the time of invention.

Federal Circuit Flips “Negative Claim Limitation” Decision after Change in Panel Composition

By Chris Holman

Novartis Pharms. Corp. v. Accord Healthcare, Inc., 2022 WL 2204163, — 4th —  (Fed. Cir. June 21, 2022)

Here we have a case in which a petition for rehearing by the Federal Circuit leads to a flipped decision that appears to be the consequence of a change in panel composition.

In the original decision, authored by Judge O’Malley and decided January 3, a divided panel upheld a district court’s determination that the patent claims at issue were not invalid for failure to satisfy the written description requirement. The Federal Circuit agreed to rehear the case, but the composition of the panel rehearing the case was altered by the replacement of Judge O’Malley (who retired in March) with Judge Hughes. The reconfigured panel flipped the result of the earlier decision, this time reversing the district court.  The second decision was authored by Judge Moore, the dissent in the original decision. Judge Linn, who sided with Judge O’Malley in the original decision, found himself writing in dissent the second time round.

The relevant issue before the court was whether a negative claim limitation was adequately supported by the priority patent application. The claims are directed towards methods of treating relapsing-remitting multiple sclerosis (RRMS) through the administration of fingolimod (an immune suppressant) “at a daily dosage of 0.5 mg, absent an immediately preceding loading dose regimen.”  The “no loading dose” limitation was added by amendment during prosecution in order to overcome an obviousness rejection.  A loading dose is a “higher-than-daily dose,” usually given as the first dosage in a dosing regimen.   It was undisputed that loading doses were well-known in the medical field generally, and that loading doses have been used with some medicaments used in the treatment of MS.

The priority application does not explicitly mention loading doses, let alone the absence of a loading dose, but the district court nonetheless found implicit support for the negative claim limitation in two examples provided in the specification (one a prophetic human clinical trial, the other an experiment conducted in rats) which disclosed dosage regimens that did not involve the use of an initial loading dose. There was expert testimony to the effect that a person of skill in the art (POSA) reading the examples would have understood them as being “complete,” and as such the fact that the examples do not mention a loading dose implicitly discloses a dosage regimen that is not preceded by a loading dose.

In the original decision upholding the district court’s decision as not erroneous, Judge O’Malley emphasized that the majority was not instituting a “new and heightened standard for negative claim limitations,” and acknowledged that the disclosure need not describe a limitation in haec verba.  Writing in dissent, Judge Moore argued that the “no loading dose” limitation could not possibly find adequate support in a patent specification that fails to even mention loading doses.

Writing for the majority in the second opinion, Judge Moore reiterates her position that the district court clearly erred in finding written description support for the “no loading dose” limitation. While she acknowledges that a negative claim limitation does not necessarily require explicit written description support when the specification describes a reason to exclude the relevant element, e.g., when the specification identifies disadvantages of using that element, or “distinguishes among” the element and alternatives to it, she maintains that the element must at least be disclosed in some form, given that “the hallmark of written description is disclosure.” Judge Moore does not dispute that the written description requirement can be satisfied if a skilled artisan would have understood that the specification inherently discloses the negative limitation, but she found no evidence on the record in this case that a skilled artisan would understand silence regarding a loading dose to “necessarily exclude” a loading dose.

In his dissent, Judge Linn does not so much disagree with Judge Moore’s characterization of the law of written description, as with the way the majority applied that law to the facts of this case. In particular, he complains that majority improperly required the priority application to disclose that the negative limitation in question was “necessarily excluded”.  He argues that it can be sufficient for the specification to merely provide a “reason to exclude” the negative claim limitation.


Induced Infringement and the Section 286 Statute of Limitations

By Chris Holman

Roche Diagnostics Corp. v. Meso Scale Diagnostics, LLC, 2022 WL 1052320, — 4th —  (Fed. Cir. Apr. 8, 2022)

Through its acquisition of BioVeris Corporation, Roche Diagnostics became the owner of various patents relating to immunoassays employing electrochemiluminescence (“ECL”). In spite of its ownership of the patents, however, a jury found that a predecessor of BioVeris (IGEN) had exclusively licensed the patents to Meso Scale Diagnostics, and that Roche was liable to Meso for directly infringing one of the patents, and for inducing infringement of two others. On appeal, a divided Federal Circuit affirmed the jury’s decision with respect to direct infringement, but reversed the judgment of induced infringement, remanding for a new trial on damages. Writing in dissent, Judge Newman would have found that Meso did not have an exclusive license in the patents, and therefore Roche was not liable for either direct or induced infringement. The decision raises interesting issues relating to induced patent infringement and the interpretation of a licensing provision.

Inducement:  In 2003, prior to acquiring BioVeris (and its ECL patents), Roche obtained a nonexclusive license to the patented ECL technology from IGEN in the field of “human patient diagnostics.”  This license required Roche to note this field restriction on its product packaging. Later, in 2007, a Roche affiliate acquired BioVeris (including over 100 patents) for approximately $600 million. Roche announced this acquisition in a press release stating it would now “own the complete patent estate of the [ECL] technology,” giving it “the opportunity to fully exploit the entire immunochemistry market” and ensuring its ability to “provide unrestricted access to all customers.” Roche also prepared a customer letter indicating that the field-restriction labels were “now obsolete” and would be “removed as soon as possible,” but that in the interim customers should “please ignore the restrictions.” Roche subsequently began selling the products without field restrictions.  Meso argued that these actions induced customers to use the patented technology outside of the licensed field of use, i.e., “human patient diagnostics.”

Writing for the majority, Judge Prost explained that the decision to reverse the district court’s judgment with respect to induced infringement rested on two independent grounds: (A) absence of intent, and (B) absence of an inducing act that could support liability during the six-year statute of limitations on collecting back-damages, as set forth in 35 U.S.C. § 286.  (In a 2019 post, Dennis explains why it is correct to refer to the Section 286 limitation on damages as a “statute of limitations.”  For the record, Judge Newman uses the term in her  Roche Diagnostics dissent.)

Regarding absence of intent, the court found that the district court had, in denying JMOL, “incorrectly applied a negligence standard rather than requiring specific intent for inducement.” Judge Prost explained that:

While it’s true that we previously applied a “knew or should have known” formulation, we’ve since made clear that, “to the extent our prior case law allowed the finding of induced infringement based on recklessness or negligence, such case law is inconsistent with Global-Tech and no longer good law.”  …  Under the proper standard, the jury’s inducement conclusion is unsupportable.

The majority went on to explain that a finding of induced infringement was fundamentally inconsistent with the district courts conclusion (made in the context of a JMOL of no willful infringement) that “at no time did Roche have a subjective intent to infringe (or induce infringement of) Meso’s patent rights.”  In particular, the district court found that Roche had reasonably (albeit ultimately incorrectly) concluded that Meso did not have an exclusive license in the patents, and thus that Roche had no liability to Meso for patent infringement. Judge Prost explained that:

In some respects, the intent standard for inducement is akin to the one for willfulness, as both rest on the subjective intent of the accused infringer. … Here, the jury’s verdict of inducement couldn’t have survived JMOL under the proper intent standard because it contradicts the court’s express findings regarding Roche’s subjective belief that it wasn’t infringing or inducing infringement.

The majority further found that Meso had not proven that Roche had committed inducing acts within the Section 286 patent-damages limitations period, which began in April 2011. In particular, Roche’s allegedly inducing acts, i.e., its press release, customer letter, and decision to stop affixing field-restriction labels, occurred solely in 2007.

In sustaining the jury’s verdict of induced infringement, the district court had posited that acts occurring before the damages period could support a finding of inducement if they “continued to have an impact and caused third parties to use the products-at-issue outside of the licensed patient-diagnostics field after April 2011.”  The majority rejected the district court’s “continuing-impact” standard, citing Standard Oil Co. v. Nippon Shokubai Kagaku Kogyo Co., 754 F.2d 345 (Fed. Cir. 1985), and finding that “Roche’s press release, customer letter, and removal of field restrictions cannot support the jury’s induced-infringement verdict because the evidence indicates—and Meso doesn’t dispute—that none of these acts occurred within the damages period.”

Meso argued that Roche had committed inducing acts during the damages period because Roche “sold the products without restrictive labels throughout the damages period.” But the majority found that “sales without restrictive labels are not acts of inducement where, as here, the products have both in-field (non-infringing) and out-of-field (infringing) applications.”

The court further found that:

Even if Standard Oil doesn’t foreclose the district court’s “continuing-impact” standard, we reach the same conclusion because Meso didn’t provide evidence of causation between the allegedly inducing acts (before the damages period) and the direct infringement (within the damages period). Specifically, Meso put forward no evidence that any customers purchasing Roche’s products during the damages period received the 2007 communication and, in reliance on it, used the products out-of-field. …  For similar reasons, Meso’s argument that Roche induced infringement because it “never withdrew” its 2007 guidance also fails, at least because Meso didn’t show that this omission caused customers to infringe.

Readers might find it interesting to compare Judge Prost’s opinion in this case with her dissent in the Federal Circuit’s recent “skinny label” decision, Glaxosmithkline v. Teva, 7 F.4th 1320 (Fed. Cir. 2021) wherein she discusses induced infringement, and particularly her interpretation of the causation element of inducement.

License Scope:  Meso’s exclusive license in the ECL patents arose out of a joint venture agreement between IGEN and Meso Scale Technologies, a company owned by Jacob Wohlstadter (son of IGEN CEO Samuel Wohlstadter).  The agreement specified a “Research Program” for Meso to perform and included the following license provision:

2.1. IGEN Technology. IGEN hereby grants to [Meso] an exclusive, worldwide, royalty-free license to practice the IGEN Technology to make, use and sell products or processes (A) developed in the course of the Research Program, or (B) utilizing or related to the Research Technologies; provided that IGEN shall not be required to grant [Meso] a license to any technology that is subject to exclusive licenses to third parties granted prior to the date hereof. In the event any such exclusive license terminates, or IGEN is otherwise no longer restricted by such license from licensing such technology to [Meso], such technology shall be, and hereby is, licensed to [Meso] pursuant thereto.

With respect to the directly infringed patent, the majority affirmed the district court’s determination that the patent was “developed in the course of the Research Program,” and therefore, under “prong A” of the provision, Meso had exclusive rights in the asserted claim.  The court noted that “the work that was done in this patent was part of the research program,” and that Roche had not provided any persuasive reason why the asserted claim wasn’t “developed in the course of the Research Program.”  According to the majority:

The most Roche offers on this score is a footnote arguing generally that “the evidence at trial was insufficient for the jury to find that Meso held exclusive rights to the entirety of the ‘939 patent claim” and citing further course-of-conduct evidence. But this argument, “made in passing only in a footnote, is not sufficient under our precedents to preserve an argument for review.”

The majority found it unnecessary to decide whether Meso had an exclusive license in the patent claims that were only infringed indirectly, given that the district court’s finding of induced infringement had been reversed.

Writing in dissent, Judge Newman argued that Roche was not liable for infringement of any of the patents, since, under her interpretation of the license provision, Meso did not have an exclusive license to any of them.  She found the jury’s verdict to be “contradicted by the activity of all parties at the time of the 1995 license and the ensuing twenty-two years (citing Old Colony Tr. Co. v. City of Omaha, 230 U.S. 100, 118 (1913) (The practical interpretation of a contract by the parties to it for any considerable period of time before it comes to be the subject of controversy is deemed of great, if not controlling, influence)).”

Judge Newman also took issue with what she she saw as the majority’s decision to “disregard[] the undisputed evidence of [Meso]’s acceptance of Roche’s rights, because Roche mentioned that evidence in a footnote.” In her view:

Although presented in footnotes, these arguments were fully developed. The majority’s holding that Roche forfeited this issue defeats “the orderly administration of justice,” instead presenting a trap for the unwary. The judicial obligation is to seek truth and justice, even from footnotes.

Clearly, an attorney addressing the court should think twice before using a footnote to make a substantive point.

The Definiteness Implications of Using “Examples” to Define Claim Terms

by Chris Holman

ImmunoGen, Inc. v. Hirshfeld, 2022 WL 885774, (Fed. Cir. Mar. 25, 2022) (nonprecedential)

The patent application at issue in this case claims a method of treating a cancer patient by administering mirvetuximab (an immunoconjugate drug) “at a dose of 6 milligrams (mg) per kilogram (kg) of adjusted ideal body weight (AIBW) of the patient.” The purported invention arose out of the discovery that administration of mirvetuximab at the recited dosage significantly reduces the severe ocular side effects that were observed during Phase 1 clinical trials when the drug was administered at a dose of 7 mg per kg of the patient’s total body weight (“TBW”).  After the Patent Trial and Appeal Board (“Board”) affirmed the examiner’s rejection of the pending claims for obviousness and obviousness-type double patenting, the applicant (ImmunoGen) filed a § 145 suit in the Eastern District of Virginia challenging the rejections.  The district court determined on summary judgment that the claims are “fatally indefinite and fatally obvious” as a matter of law.  On appeal, the Federal Circuit vacated the grant of summary judgment and remanded for further proceedings.

The district court’s indefiniteness ruling was based on the claims’ recitation of “AIBW,” a term which the court found was not defined in the application in manner that would inform a skilled artisan, with reasonable certainty, as to the scope of the invention (the Nautilus standard).  The application defines AIBW as “a size descriptor that accounts for sex, total body weight, and height.” It further defines ideal body weight (“IBW”), which is used to calculate AIBW, as “an estimate of weight corrected for sex and height, and optionally frame size.”  The AIBW and IBW definitions each includes a specific formula, introduced by the phrase “for example,” for calculating the respective values.

The formulas are reproduced below in the form of equations:

AIBW = IBW + 0.4(Actual weight in kg – IBW)

IBW (male) = 0.9(Height in centimeters) – 88

IBW (female) = 0.9(Height in centimeters) – 92

These “example” formulas were also reproduced in Example 4 of the application, which relates to the dosing of mirvetuximab.

In support of its decision finding the claims indefinite, the district court relied primarily on the fact that the definitions section of the application preceded the AIBW formula with the language “for example,” which the court found “ma[de] clear that there are multiple ways to calculate AIBW,” thereby “leav[ing] a skilled artisan to wonder or to guess whether the formula provided is the only one covered by the ’809 Application.” This uncertainty was, in the view of the district court, compounded by: (1) similar “for example” language accompanying the IBW formula; (2) the disclosure that IBW corrects “for sex and height, and optionally frame size”; and the incorporation by reference in its entirety of “Green,” an article that discloses several methods for calculating IBW and lists correction factors, each specific to a different drug, that can be used to adjust IBW to AIBW.

On appeal, the Federal Circuit found that the material factual findings underlying the district court’s definiteness ruling were far from undisputed. In particular, ImmunoGen had identified other intrinsic evidence a skilled artisan would consider in determining the scope of the claims, including that: (1) the claims and specification are drawn to a specific dosing regimen for a specific immunoconjugate, which is significant in light of expert testimony that the correction factor used to calculate AIBW is drug-specific; (2) Example 4 describes dosing mirvetuximab in accordance with the claimed method and uses the same AIBW and IBW formulas disclosed in the definitions section; and (3) during the prosecution of the ’809 Application, the USPTO never disputed the definiteness, or gave any indication it failed to understand the meaning, of the now-allegedly indefinite term. ImmunoGen also presented extrinsic evidence regarding the knowledge of a skilled artisan. For instance, both parties’ experts testified that AIBW dosing involves drug-specific formulas and correction factors.

The Federal Circuit also found that the district court had erred in concluding that there was no disputed question of material fact with respect to obviousness.  It was undisputed that AIBW dosing had not previously been used for mirvetuximab, or for that matter any other immunoconjugate drug.

If on remand the court ultimately finds the claims indefinite for defining a critical claim limitation in terms of an “example,” it would not be the first time that the Federal Circuit has flagged this as an issue.  In Interval Licensing LLC v. AOL, Inc., 766 F.3d 1364 (Fed. Cir. 2014), the Federal Circuit held claims invalid for indefiniteness because the specification failed to adequately define the claim limitation “unobtrusive manner that does not distract a user.”  While “recognizing that a patent which defines a claim phrase through examples may satisfy the definiteness requirement,” the court “decline[d] to cull out a single “e.g.” phrase from a lengthy written description to serve as the exclusive definition of a facially subjective claim term.”  The court observed that “[h]ad the phrase been cast as a definition instead of as an example—if the phrase had been preceded by “i.e.” instead of “e.g.”—then it would help provide the clarity that the specification lacks.”

Still, I think that Interval Licensing can be readily distinguished over ImmunoGen, in that Interval Licensing’s “unobtrusive manner that does not distract the user” claim limitation seems much more “facially subjective” than ImmunoGen’s “adjusted ideal body weight.”