United States: PTAB Institutes Post Grant Review Against Chemical Process Patent

The USPTO Patent Trial and Appeal Board has instituted Post Grant Review (PGR) proceedings against a patent directed to a process for treating contaminated media. The petition for PGR challenged that patent on written description, enablement, prior art and eligibility grounds, but the PTAB instituted proceedings only as to written description. This case provides an interesting glimpse into the types of issues likely to be raised in PGR petitions, and how the PTAB may analyze them.

The Patent At Issue

The patent at issue is U.S. Patent No. 9,126,245, assigned to Innovative Environmental Technologies, Inc. The PTAB identified claim 1 as representative:

1. A method for chemical oxidation followed by a biological attenuation process of an environmental medium containing one or more contaminants, the method comprising,
introducing persulfate and one or more trivalent metals into the environmental medium, wherein the one or more trivalent metals activate the persulfate in order to chemically oxidize the one or more contaminants, wherein amount of the persulfate is selected to chemically oxidize the one or more contaminants and amount of the one or more trivalent metals is between approximately 17-30% of molecular weight of the persulfate so that at conclusion of the chemical oxidation sufficient residual sulfate and sufficient residual trivalent metals remain such that:
naturally occurring facultative cultures utilize the residual sulfate and the residual trivalent metal as terminal electron acceptors to promote the biological attenuation process of the one or more contaminants; and
the residual sulfate and the residual trivalent metal prevent formation and accumulation of hydrogen sulfide which is a toxin to the facultative cultures.

The Grounds For Post Grant Review

The '245 patent is subject to PGR because it was filed May 10, 2013 with no earlier claim for priority. PeroxyChem LLC filed the petition for PGR about 2 months after the patent granted, well-within the 9-month window set forth in 35 U.S.C. § 321(c). The Patent Owner did not file a Preliminary Response. Neither party identified any related proceedings.

The written description challenge was based on the 17-30% ratio of trivalent metals to persulfate not being described in the specification. According to the Petitioner, when that feature was added to the claims the Patent Owner "set forth 13 steps to explain how the ratio was derived," but those steps "include several significant assumptions and requirements that are not found in the claims or the specification." The PTAB agreed "that it is more likely than not that the challenged claims are unpatentable under 35 U.S.C. § 112(a) because the Specification of the '245 patent does not provide adequate written-description support, at least for the 17–30% ratio recited in the claims."

The enablement challenge was based on the assertion that the 'patent "fails to describe the necessary environmental conditions, and necessary parameters, that must be present in order for the claimed chemical reactions to take place, or how a POSA would select or identify the appropriate environmental conditions." The PTAB noted that the Petitioner had not analyzed the claims under the Wands factors, and found that "all challenged claims are method claims, each of which requires the single step .... The Specification of the '245 patent discloses how the remedial materials are introduced, ... [and] explains the chemical oxidation and biological attenuation processes." Thus, the PTAB did not find it more likely than not that Petitioner would succeed on its enablement challenge.

The prior art challenges were based on a single primary reference. The PTAB did not agree with Petitioner's arguments as to how the 17-30% ratio was met by that reference. Thus, the PTAB did not find it more likely than not that Petitioner would succeed on its prior art challenges.

The subject matter eligibility challenge was based on the claims being directed to conventional activity and natural phenomena. In particular, as summarized in the PTAB institution decision:

According to Petitioner, the challenged claims "are method claims and recite only a single step—'introducing persulfate and one or more trivalent metals into an environmental medium'—which was conventional activity . . . and the remaining elements merely recite the theoretical natural phenomena."

The PTAB did not find it more likely than not that Petitioner would succeed on this ground:

Even assuming the chemical oxidation and biological attention recited in the claims are, as Petitioner characterizes, "natural phenomena," a process is not unpatentable simply because it recites natural phenomena. See Diamond v. Diehr, 450 U.S. 175, 187 (1981); see also Mayo Collaborative Servs. v. Prometheus Labs., 132 S. Ct. 1289, 1297 (2012) (stating that the steps of administering a drug to a patient and determining the resultant level of a metabolite in the patient "are not themselves natural laws"). Instead, applications of such phenomena to a new and useful end remain eligible for patent protection. Diehr, 450 U.S. at 187.

Here, each challenged claim recites chemical and biological reactions that, according to Petitioner, "may occur naturally." Pet. 75. Each claim as a whole, however, is directed a method of practically combining the reactions to remove soil and groundwater contaminants. The method employs the reactions; but it does not preempt the use of the reactions. See Diehr, 450 U.S. at 187. Indeed, the claim not only recites the step of introducing persulfate and trivalent metals into the contaminated medium, but also requires a specific ratio (17–30%) between the trivalent metals and persulfate .... As such, no challenged claim as a whole is directed to any natural phenomena.

Thus, the PTAB instituted PGR on written description grounds only.

Will We See A Flood Of Post Grant Review Petitions?

In theory, pharmaceutical and biotechnology patents may be more vulnerable to Post Grant Review proceedings than Inter Partes Review proceedings, because of the ability to raise written description, enablement and subject matter eligibility issues. In reality, competitors will need to be ready to challenge patents shortly after grant–and willing to show their hands if they are not already involved in parallel litigation proceedings. Will these requirements prevent a flood of PGR petitions?

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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