Guest post by Professor Kevin Emerson Collins, Washington University School of Law.
Praxair Distribution, Inc. v. Mallinckrodt Hospital Products IP LTD., 2018 U.S. App. LEXIS 12707 (Fed. Cir. 2018)
In a divided opinion, the Federal Circuit held that all of the claims challenged in an IPR were obvious, upholding the PTAB’s obviousness determination with respect to most of the claims but reversing its nonobviousness determination with respect to a few. Praxair Distribution raises of a number of distinct, yet interrelated, issues concerning the cryptic, yet essential, printed matter doctrine: the opinion addresses the doctrine’s extension to mental steps, its implications for the relationship between sections 101 and 102/103, and the breadth of its functional-relation exception.
U.S. Patent 8,846,112 covers methods of distributing nitric oxide gas cylinders for pharmaceutical applications. Inhaling nitric oxide dilates blood vessels in the lungs and improves blood oxygenation, and it is approved for treating neonates with hypoxic respiratory failure. The prior art taught that inhaled nitric oxide may lead to pulmonary edema, a serious adverse event, in neonates with left ventricular dysfunction. The claims of the ‘112 patent address methods that build on this prior art. Roughly, the claims can be sorted into three groups: the informing claims, the informing-and-evaluating claims, and the informing-and-discontinuing-treatment claims. This commentary addresses each of these three groups of claims in turn.
The Informing Claims: Easy Cases?
In gross, the informing claims recite supplying nitric oxide to a medical provider and providing the medical provider with information relevant to the clinical use of the nitric oxide on neonatal patients. Claim 1, for instance, includes the steps of:
- “supplying the cylinder containing compressed nitric oxide gas to a medical provider responsible for treating neonates” and
- “providing to the medical provider (i) information” about the recommended dose for neonates with hypoxic respiratory failure “and (ii) information” about the risk of that dose for neonates with left ventricular dysfunction, wherein “the information of (ii) [is] sufficient to cause a medical provider … to elect to avoid treating one or more” neonates with left ventricular dysfunction in order “to avoid putting [them] at risk of pulmonary edema.”
The PTAB held, and the Federal Circuit affirmed in a majority opinion authored by Judge Lourie and joined by Chief Judge Prost, that the informing claims were unpatentable as obvious under the printed matter doctrine. Under recent Federal Circuit precedent, the informing claims present an easy case of unpatentability. The printed matter doctrine states that “[c]laim limitations directed to printed matter are not entitled to patentable weight unless the printed matter is functionally related to the substrate on which the printed matter is applied.” Opinion at *9. If a limitation is not given patentable weight, it cannot be relied upon to distinguish the claimed invention from the prior art in the novelty or nonobviousness analyses. In claim 1, the limitations apart from the providing-information limitation are obvious in light of the prior art as an ordered combination, and the providing-information limitation cannot be given patentable weight. Federal Circuit precedent clearly establishes that printing information about how to use a product onto that product as a substrate does not create a functional relationship between the printed matter and the substrate. See, e.g., In re Ngai, 367 F.3d 1336 (Fed. Cir. 2004). But see In re Miller, 418 F.2d 1392 (CCPA 1969) (finding a functional relationship between volumetric indicia and the measuring spoons on which they were printed). Importantly, the printed matter doctrine still applies even though the providing-information limitation does not require the information to be in the form of printed matter per se. In King Pharmaceuticals v. Eon Labs and In re Kao, the Federal Circuit had already extended the printed matter doctrine to encompass the conveyance of information in non-printed forms, such as verbal speech or sign language. See, Kevin Emerson Collins, An Initial Comment on King Pharmaceuticals: The Printed Matter Doctrine as a Structural Doctrine and Its Implications for Prometheus Laboratories, 2010 Patently-O Patent L.J. 111.
Not only is the lack of patentable weight for “informing”-type limitations settled law, but it is good policy, as well. As I have repeatedly argued elsewhere, the core of the printed matter doctrine, as well as its expansion to information conveyed through speech and other non-print media, is necessary to ensure that the knowledge disclosed in patent specifications remains free for all to use qua knowledge during the term of the patent. Kevin Emerson Collins, The Structural Implications of Inventors’ Disclosure Obligations, 69 Vand. L. Rev. 1785 (2016); Kevin Emerson Collins, The Knowledge/Embodiment Dichotomy, 47 U.C. Davis L. Rev. 1279 (2014). Claim limitations that read on communicative acts can restrain the diffusion of the teachings contained in patent disclosures, so a broad interpretation of the printed matter doctrine is necessary to ensure that patentee’s exclusive rights to claimed inventions cannot interfere with the free dissemination of the informational content of patent specifications.
The Informing-and-Evaluating Claims: Mental Steps and Patent Eligibility
The informing-and-evaluating claims depend from the informing claims, adding a number of steps to be performed, presumptively, by medical providers who use nitric oxide. (Bracket the divided infringement issue afoot here.) For example, claim 3 adds inter alia the following limitations to claim 1:
- identifying a neonate with hypoxic respiratory failure,
- determining whether the neonate has left ventricular dysfunction, and
- “evaluating the potential benefit of treating” that neonate with nitric oxide “vs. the potential risk” of doing so.
The PTAB and the Federal Circuit both identify the evaluating limitation as a mental step performed in a medical provider’s mind. They then both extend the printed matter doctrine to preclude giving patentable weight to mental steps and, as a result, hold the informing-and-evaluating claims obvious. The Federal Circuit breaks new ground by extending the printed matter doctrine to mental activity in this manner, and Judge Newman’s concurrence argues that the extension is not proper. Simply put, “[m]ental steps are mental, not printed.” Concurrence at *1. (The concurrence may also be read more broadly to suggest that even the extension of the printed matter doctrine to spoken information in King Pharmaceuticals, discussed in the previous section addressing the informing claims, is legal error.)
Given the policy concerns discussed above for extending the printed matter doctrine to speech, however, I believe that its extension to at least some mental steps is a logical and justifiable move. As Judge Louie correctly notes, the evaluating limitation:
requires a medical provider to think about the information claimed in the providing information limitation of claim 1. But adding an ineligible mental process to ineligible information still leaves the claim limitation directed to printed matter. To hold otherwise would make the printed matter doctrine a dead letter, requiring no more than a “think about it” step to give patentable weight to a claim limitation directed to information content. There is no meaningful distinction between claim limitations directed to written information … verbal information … and mentally-processed information.
Opinion at *13. In brief, the extension of the printed matter doctrine to encompass “mentally-processed information” prevents form from trumping substance.
Although Praxair Distribution does not expressly make this point, it seems to revive some variant of the historical mental steps doctrine. In the mid-twentieth century, the mental steps doctrine did for mental steps what the printed matter does today for printed matter: it invalidated claims that relied on the content of mental processes to establish a distinction from the prior art. See, e.g., In re Abrams, 188 F.2d 165, 165 (C.C.P.A. 1951). The PTAB cited to some of these mid-century mental steps cases to support its extension of the printed matter doctrine to mental steps. 2016 WL 3648375 at *10 (2016). The Federal Circuit, however, did not, most likely because the CCPA abandoned the mental steps doctrine decades ago in the course of grappling with the patent eligibility of software, In re Musgrave, 431 F.2d 882, 889 (C.C.P.A. 1970), and the Federal Circuit has refused to reinstate it, Prometheus Labs. v. Mayo Collaborative Servs., 628 F.3d 1347, 1358–59 (Fed. Cir. 2010). Nonetheless, in practice, if not in name, Praxair Distribution plainly reinvigorates some variant of the mental steps doctrine. Technically, the opinion could be read narrowly so that the printed matter doctrine only extends to mental steps when claims recite both a printed matter limitation with certain informational content and a think-about-it limitation to the same informational content. However, the argument that the informational content of an evaluating, think-about-it limitation should be given patentable weight if the informing limitation is removed from the claim is difficult to fathom.
Another interesting aspect of Praxair Distribution is that it opens a new front in the ongoing debate concerning the intermixing of sections 102 and 103, on the one hand, and section 101, on the other hand. The Supreme Court’s opinions on patent eligibility in Mayo and Alice are highly controversial, in part, because their “inventive concept” analysis—i.e., what is now known as Mayo/Alice “step 2″—requires consideration of the advance over the prior art, a factual issue that is usually addressed in the novelty and nonobviousness analyses. Mixing the patentability requirements in the other direction—that is, using 101 concerns to inform 102/103 doctrine—has to date not received much attention. However, the printed matter doctrine has long mixed in this other direction, and Praxair Distribution brings this other-direction mixing into the spotlight:
Claim limitations directed to the content of information and lacking a requisite functional relationship are not entitled to patentable weight because such information is not patent eligible subject matter under 35 U.S.C. § 101. Cf. Mayo Collaborative Servs. v. Prometheus Labs., Inc., 566 U.S. 66, 90 (2012). While the doctrine’s underlying rationale is in subject matter eligibility, its application has been in analyzing other patentability requirements, including novelty … and nonobviousness.
Opinion at *10. (Interestingly, the European Union, too, mixes patent-eligibility concerns into the inventive step analysis with its requirement that that the inventive step reside in a technical effect. European Patent Office, Guidelines for Examination, Part G, Chapter VII.5.2.) The printed matter doctrine reveals that, at least under limited circumstances, what are often conceived of as the rigid statutory silos of patent law must break down. As Judge Newman notes in her concurrence, the printed matter doctrine started out as a prohibition on patenting business forms that was administered as part of the doctrine of patent eligibility. Concurrence at 2–3. However, over time, as patent applicants attempted to claim printed matter in combination with otherwise patent-eligible subject matter, the doctrine developed the two statutory branches that it has today: it is administered via section 101 in cases that involve claims to printed matter per se and via sections 102 and 103 in cases that involve claims to printed matter in combination with statutory processes, machines, manufactures, or compositions of matter. The extension of the printed matter doctrine to mental steps merely further highlights the mixing that is already occurring because mental processes are today, understood, well-understood to be the basis of patent-eligibility rejections. The mental steps doctrine, that the printed matter doctrine now resembles, was administered entirely as a section 101 doctrine, employing the equivalent of a patentable-weight analysis as part of patent eligibility. It never partially migrated from section 101 into sections 102 and 103 like the printed matter doctrine did.
Finally, the dispute underlying the Praxair Distribution opinion also reveals an overlap between sections 102 and 103 and section 101 in yet another way. The parallel district court proceeding invalidated all claims of the ‘112 patent that were at issue for lack of patent eligibility under Mayo, although the representative claim was a more conventional diagnostic claim from a different patent. 2017 WL 387649, *14–*20. The PTAB, of course, could consider this section 101 ground because it is limited in IPRs to 102 and 103 grounds.
The Informing-and-Discontinuing-Treatment Claims: An Expansive Functional-Relation Exception
Like the informing-and-evaluating claims, the final group of claims also depends from an informing claim. Technically, however, these claims depend from a claim that requires slightly different information to be provided to the medical provider with the nitric oxide cylinders, namely information in the form of a “recommendation that, if pulmonary edema occurs in a [neonate] who has pre-existing left ventricular dysfunction … the treatment with … nitric oxide should be discontinued.” Again like the informing-and-evaluating claims, they add further steps presumptively performed by medical providers to the steps performed by nitric oxide distributors. The representative claim here is claim 9. After reciting the limitations of identifying a neonate with hypoxic respiratory failure and determining whether the neonate has left ventricular dysfunction, it adds treatment and treatment-cessation steps:
- “treating the neonatal patient with left ventricular dysfunction with … nitric oxide, whereupon the [neonate] experiences pulmonary edema; and
- in accordance with [the information provided], discontinuing the … nitric oxide due to the neonatal patient’s pulmonary edema.”
The PTAB held claim 9 not unpatentable as obvious. It construed the “in accordance with” language to mean that the discontinuation of the treatment was performed “based on, or as a result of” the information/recommendation provided with the nitric oxide cylinders. It then concluded that the fact that the information was the reason or motivation for the medical provider to discontinue treatment created a functional relationship between the information and the discontinuing-treatment step. Opinion at *6. In turn, the PTAB held that the functional-relation exception to the printed matter doctrine applied, that the information provided could be given patentable weight, and that claim 9 was not obvious.
The Federal Circuit approved of the PTAB’s interpretation of the functional-relation exception to the printed matter doctrine as well as its application to claim 9. Opinion at *17. However, the Federal Circuit reversed the PTAB’s ultimate nonobviousness determination, concluding that, even when the content of the information is given patentable weight, the claim is obvious in light of the prior art. The prior art taught that nitric oxide may be given to patients with left ventricular dysfunction as long as those patients are monitored during treatment. The information provided—namely that nitric oxide should be discontinued for patients with left ventricular dysfunction upon pulmonary edema—was too small of an advance over the prior art to render the claim patentable.
The point of agreement between the PTAB and the Federal Circuit on the expansive interpretation of the functional-relation exception raises an interesting—and possibly troubling—precedent for future cases. The logical reason for a real-world, extra-mental action can now distinguish a claim reciting the action from the prior art. That is, the “invention” of a nonobvious mental motivation for a human actor to perform an already-known, real-world (i.e., non-mental) action, like discontinuing treatment, can give rise to a patentable method claim.
Consider a simple hypothetical. Assume that doctors routinely decrease the dosage of a drug when a metabolite of the drug in a patient’s bloodstream exceeds a certain threshold because of a known potential for a serious adverse event, namely liver problems. Now assume that a researcher discovers that, unexpectedly, the same metabolite in a patient’s bloodstream exceeding the same threshold also raises the risk of a different, serious adverse event, namely heart problems. The researcher claims a method of a medical provider: (a) administering a dose of a drug to a patient from a package with a printed indication that a metabolite level exceeding a threshold creates a medically unacceptable risk of heart problems, (b) determining the level of the drug’s metabolite in the patient’s bloodstream, and (c) reducing the dosage of the drug “in accordance with” the printed indication (i.e., due to the risk of heart problems) if the threshold is exceeded. Even though the medical provider infringing the claim performs conduct that, to an external observer, cannot be differentiated from the prior art (except for the printed indication on the drug package), the claim is patentable. The functional-relation exception to the printed matter doctrine allows the content of the printed matter be given patentable weight because the information conveyed motivates the medical provider’s conduct, and the unexpected nature of the connection between high metabolite levels and heart problems strongly supports nonobviousness.
To be clear, even if one finds the patentability of this hypothetical claim to be problematic—and reasonable minds may differ on whether it is problematic—there is no reason to question the Federal Circuit’s actual holding concerning claim 9 in Praxair Distribution. The Federal Circuit held the claim unpatentable for obviousness even when it gave the content of the printed (or spoken or thought) matter patentable weight. By necessity, it therefore would have reached the same holding if it had refused to give that content patentable weight. The expansiveness of the functional-relation exception in Praxair Distribution will only become outcome-determinative in future cases when a claim recites information that provides an unexpected reason or motivation for a real-world, extra-mental action that, standing alone, is known or is merely an obvious departure from the prior art.
Inversely, a narrow interpretation of the functional-relation exception—one that does not label the content of information as functionally related to an action recited as a limitation when the action is performed because of the information—would not widely undermine patentability. In particular, it would not invalidate most claims to actions that are motivated by newly discovered information. For example, consider a researcher who discovers that, unexpectedly, a particular genetic mutation means that a patient should be taking a lower dosage of a drug. The researcher may claim a method of a medical provider: (a) testing a patient for the mutation and (b) administering the lower drug dosage to the patient if the mutation is present. The printed matter doctrine is irrelevant to the nonobviousness of this claim because the claim does not recite the content of printed information (or a mental state of a doctor who thinks about the information) as a limitation. Such an information limitation is not required for validity, and would thus be unnecessary drafting surplusage, because the real-world (non-mental) conduct of testing and administering under the specified conditions is sufficient to distinguish the claim from the prior art. Although it is not recited as a claim limitation, the newly discovered information still provides an explanation for why the claimed invention is useful and why it produces unexpected results. (Further highlighting the interconnection of the printed matter doctrine and patent eligibility, compare the outcome in this hypothetical to the Federal Circuit’s recent holding in Vanda Pharmaceuticals Inc. v. West-Ward Pharms Int’l Ltd., 887 F.3d 1117 (Fed. Cir. 2018), which upheld the patent eligibility of a hybrid diagnostic/treatment claim under Mayo.)
The Federal Circuit’s expansive interpretation of the functional-relation exception to the printed matter doctrine in Praxair Distribution can be traced to a recent shift how the Federal Circuit articulates that exception. Traditionally, the functional-relation exception was applied only when there was a functional relationship between the content of the printed matter “the substrate on which the printed matter is applied.” Opinion at *9 (emphasis added). For example, in one of the few non-software cases in which the Federal Circuit actually held that the functional-relation exception allowed the content of printed matter to receive patentable weight, the content of a series of numbers printed on a loop of paper was held to be functionally related to the substrate/paper because the numbers themselves were a looping series. In re Gulack, 703 F.2d 1381 (Fed. Cir. 1983). In contrast, the PTAB and the Federal Circuit in Praxair Distribution looked for, and found, a functional relationship between the content of the printed matter and a different limitation in the claim other than the printed-matter limitation, namely the discontinuing-treatment limitation. From my quick research, Praxair Distribution appears to be the first case in which the functional-relation exception has been found to apply based on a functional relationship between printed matter and a claim limitation directed to something other than the printed matter’s substrate. Both King Pharms. and Kao use language that suggest the possibility of such a non-substrate relationship satisfying the functional-relation exception, but neither finds that it exists on the facts presented. If the functional-relation exception were limited to claims in which there is a functional relationship between the printed matter and the substrate in particular, then claims to new motivations for already-performed conduct would not be patentable under the printed matter doctrine.