In Praxair Distribution, Inc. v. Mallinckrodt Hospital Products IP Ltd., [2016-2616, 2016-2656](May 16, 2018), the Federal Circuit affirmed the PTAB decision that claims 1–8 and 10–11 of U.S. Patent 8,846,112 directed to methods of distributing nitric oxide gas cylinders for pharmaceutical applications were unpatentable as obvious, and reversed the decision that claim 9 was not unpatentable.

In construing the claims, the Board applied the printed matter doctrine. The Board interpreted 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.

With respect to claim 9, however, the Board interpreted “in accordance with” to mean “based on, or as a result of” the recommendation to discontinue nitric oxide treatment from claim 7, thereby establishing a functional relationship to the recommendation limitation. The Board found that the cited prior art collectively taught each limitation of claims 1–8 and 10–19 that did have patentable weight, and held they were obvious.

The Federal Circuit began with the printed matter doctrine, applied by the PTAB. The Federal Circuit explained that claim 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. The printed matter doctrine, however, is not limited to printed materials, and applies if the claims are directed to the content of information.

If 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, while where the printed matter is not functionally related to the substrate, the printed matter will not distinguish the invention from the prior art in terms of patentability. In Ngai, there was no functional relationship between claimed instructions and a diagnostic kit, as the instructions “in no way depended on the kit, and the kit did not depend on the” instructions. However, Ngai distinguished Gulack, where there was a functional relationship between printed digits on a circular band because “the printed matter and the circularity of the band were interrelated, so as to produce a new product useful for educational and recreational mathematical purposes.”

The Federal Circuit agreed that the Board properly addressed the printed matter doctrine during claim construction. The Federal Circuit rejected Mallinckrodt’s argument that the printed matter/mental steps doctrines only apply to patent eligibility, noted that the printed matter doctrine raises an issue where the § 101 patent-eligibility inquiry and the § 102 and § 103 novelty and nonobviousness inquiries overlap.

The Federal Circuit explained because claim limitations directed to mental steps may attempt to capture informational content, they may be considered printed matter lacking patentable weight in an obviousness analysis. Accordingly, a limitation that merely claims information by incorporating that information into a mental step will receive patentable weight only if the limitation is functionally related to the substrate.

The Federal Circuit noted that claim 3’s requirement that the medical provider weigh “the potential benefit of treating the [neonatal patient] with 20 ppm inhaled nitric oxide vs. the potential risk that inhaled nitric oxide could cause an increase in PCWP” merely requires a medical provider to think about the information claimed in the providing information limitation of claim 1. The Federal Circuit said that 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.

The Federal Circuit found that the reference to “pharmaceutically acceptable” referred to the nature of the nitric acid gas, not the prescribing information that may accompany it, and thus there was no functional relationship between the information and methods of providing and potentially administering the drug. Since no other functional relationship was asserted, the Federal Circuit held that the printed matter in claims 1–8 and 10 lacks a functional relationship to its substrate, and thus cannot be the basis of patentability.

The Federal Circuit then turned to claim 9, which survived the IPR, summarizing it as: (1) determining that a neonatal patient has preexisting LVD; (2) treating that neonate with nitric oxide, whereupon the neonate experiences pulmonary edema; (3) providing information and a recommendation to the medical provider to discontinue nitric oxide treatment for a patient with preexisting LVD who experiences a pulmonary edema; and (4) “based on” the recommendation, discontinuing nitric oxide treatment due to the pulmonary edema.

The Federal Circuit noted that claim 9 requires a medical provider to take a specific action, discontinuing treatment, as a result of the recommendation limitation, and agreed that this creates the required functional relationship with the rest of the claim. However, the Federal Circuit disagreed with the Board that claim 9 as a whole would not have been obvious.

The Federal Circuit found the Board improperly construed claim 9 as requiring the exclusion of persons from the treatment, rather than discontinuing persons from treatment if edema occurs, and thus the prior art teaching of treatment with monitoring  made the claimed invention obvious.