In an inter partes review proceeding, a challenger cannot raise patent-eligibility as a ground of invalidity.  Rather, the invalidity grounds are limited to lack of novelty and obviousness.  Notwithstanding, in construing claim terms, the PTAB can decide not to give patentable weight to certain claim limitations that are not patent-eligible. In Praxair Distribution., Inc. v. Mallinckrodt Hospital Products IP Ltd., No. 2016-2616, 2016-2656 (Fed. Cir. May 16, 2018) the PTAB had employed the so-called “printed matter doctrine” not to give patentable weight to certain limitations as merely “providing information”  and the CAFC affirmed the PTAB’s claim construction.

Mallinckrodt is the owner of U.S. Patent No. 8,846,112, which is directed to methods of distributing nitric oxide gas cylinders for pharmaceutical applications.

Claim 1 recites a method of providing pharmaceutically acceptable nitric oxide gas, which includes obtaining a cylinder containing compressed nitric oxide gas, supplying the cylinder to a medical provider who is responsible for treating neonates who have hypoxic respiratory failure, including some who do not have left ventricular dysfunction. Claim 1 further includes the step of providing to the medical provider “(i) information that a recommended dose of inhaled nitric oxide gas for treatment of neonates with hypoxic respiratory failure is 20 ppm nitric oxide and (ii) information that, in patients with preexisting left ventricular dysfunction, inhaled nitric oxide may increase pulmonary capillary wedge pressure (PCWP), leading to pulmonary edema, the information of (ii) being sufficient to cause a medical provider considering inhaled nitric oxide treatment for a plurality of neonatal patients who (a) are suffering from a condition for which inhaled nitric oxide is indicated, and (b) have pre-existing left ventricular dysfunction, to elect to avoid treating one or more of the plurality of patients with inhaled nitric oxide in order to avoid putting the one or more patients at risk of pulmonary edema.”

Independent claim 7 includes a “recommendation that, if pulmonary edema occurs in a patient who has pre-existing [LVD] and is treated with inhaled nitric oxide, the treatment with inhaled nitric oxide should be discontinued” (the “recommendation” limitation). Claim 9 depends on claim 7 and further comprises the following steps: performing at least one diagnostic process to identify a neonatal patient who has hypoxic respiratory failure and is a candidate for inhaled nitric oxide treatment; determining prior to treatment with inhaled nitric oxide that the neonatal patient has pre-existing left ventricular dysfunction; treating the neonatal patient with 20 ppm inhaled nitric oxide, whereupon the neonatal patient experiences pulmonary edema; and in accordance with the recommendation of [claim 7], discontinuing the treatment with inhaled nitric oxide due to the neonatal patient’s pulmonary edema. Id.

The Board applied the printed matter doctrine to interpret the providing information, evaluating, and recommendation claim limitations “to be either printed matter or purely mental steps not entitled to patentable weight, as those limitations lacked a functional relationship to the other claim limitations except in claim 9.” In particular, the PTAB was not persuaded by Mallinckrodt’s argument that the recitation of “a pharmaceutically acceptable nitric oxide gas” in the preamble of the claims would require considering information provided in the label of the supplied product.  Rather, the PTAB construed this limitation as simply “nitric oxide gas that is suitable for pharmaceutical use.”

With regard to claim 9, however, the PTAB interpreted “in accordance with” to mean “based on, as a result of” the recommendation to discontinue nitric oxide treatment from claim 7, thereby establishing a functional relationship to the recommendation limitation.

The PTAB found that the prior art cited by Praxair collectively taught each limitation of claims 1-8 and 10-19 that “have patentable weight,” and that one of ordinary skill would have been motivated to combine these references. The PTAB, however, deemed claim 9 as patentable over the cited art.  (See, final written decision in IPR2015-00529.)

On appeal, Mallinckrodt argued that the PTAB had erred “in applying the printed matter doctrine during claim construction rather than when it assessed patentability.” Mallinckrodt also argued that the PTAB had substantively misapplied the printed matter doctrine by extending it to encompass mental steps.  In addition, Mallinckrodt argued that the Board had erred in construing the term “pharmaceutically acceptable,” and that the broadest reasonable interpretation of the term would establish a functional relationship between any claimed printed matter and the other limitations of the claims.  Mallinckrodt also argued that notwithstanding claim construction, the PTAB had failed to properly consider the evidence of secondary considerations in assessing obviousness of the claimed subject matter.

The CAFC did not agree with Mallinckrodt. The CAFC noted that while early cases developing the doctrine of printed matter applied it to claims literally encompassing “printed materials,” the latter cases have not limited the doctrine to that particular factual context.  Rather, a claim limitation is directed to printed matter “if it claims the content of information.”  The PTAB emphasized that “[c]laim 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.”

The CAFC emphasized that “[w]hile the doctrine’s underlying rationale is in subject matter eligibility, its application has been in analyzing other patentability requirements, including novelty under 35 U.S.C. § 102 …” The CAFC noted that “[i]f a claim limitation is directed to printed matter, then the next step is to ascertain whether the printed matter is functionally related to its ‘substrate.’  Printed matter that is functionally related to its substrate is given patentable weight.”  The CAFC noted that it had held that “merely adding an instruction sheet or other informational content to a drug product is not sufficient to create a functional relationship, even if required by the FDA for approval.”

The CAFC held that the PTAB had correctly addressed the printed matter doctrine during claim construction. Further, the CAFC did not agree with Mallinckrodt that whether claims are directed to mental steps may only be considered in determining patent eligibility, not obviousness. The CAFC noted that like information claimed by printed matter, mental steps or processes are not patent eligible subject matter.  “And while subject matter eligibility underlies the printed matter doctrine … many of our printed matter cases have arisen in the context of anticipation or obviousness …” The CAFC noted that the printed matter doctrine “thus raises an issue where the § 101 patent-eligibility inquiry and the § 102 and § 103 novelty and nonobviousness inquiries overlap.”

The CAFC also agreed with the PTAB that the ordinary meaning of “pharmaceutically acceptable” recited in the claims preambles is the physical condition of the gas, and not prescribing information that may accompany it. Hence, the CAFC held that the PTAB did not err in concluding that this term did not create a functional relationship with the metal steps of the claims.

With regard to claim 9, however, CAFC agreed with the PTAB that the printed matter in claim 9 has a functional relationship with the rest of the claim and hence should be given patentable weight. Nonetheless, the CAFC reversed the PTAB finding on claim 9 and held that claim 9 was also obvious in view of the cited art.

With respect to the evidence of secondary considerations, the CAFC agreed with Mallinckrodt that such evidence must be considered in an obviousness analysis, but noted that the only secondary consideration evidence presented by Mallinckrodt relates to the providing information limitation, which lacks functional relationship to the rest of the claims, and hence has no patentable weight.