DuPont petitioned for inter partes review of Synvina’s patent, which was directed to a method of oxidizing a chemical using a specific temperature range, pressure range, catalyst, and solvent. The prior art disclosed the claimed solvent and catalyst, and it also disclosed ranges of temperature and pressure that overlapped with the ranges claimed in the patent. The Board held that the claims were not unpatentable as obvious. The Board concluded that DuPont had failed to show that reaction temperature and pressure were result-effective variables or that a skilled artisan would have been able to adjust those parameters to arrive at the claimed invention as a matter of routine experimentation.
DuPont appealed. Synvina argued that DuPont lacked standing to appeal the Board’s decision because DuPont had not been sued for infringement of the patent and so could “posit only speculative future harm.” The Court rejected this argument, concluding that DuPont had shown “a controversy of sufficient immediacy and reality” because (i) DuPont operated a plant capable of infringing the patent; (ii) Synvina had alleged that DuPont had copied the claimed invention; and (iii) Synvina had refused to grant DuPont a covenant not to sue.
When the ranges of a claimed composition overlap the ranges disclosed in the prior art, the Court explained, “such overlap creates a presumption of obviousness.”
On the merits, the Federal Circuit held that the Board had failed to apply the proper standards for obviousness. When the ranges of a claimed composition overlap the ranges disclosed in the prior art, the Court explained, “such overlap creates a presumption of obviousness.” The patentee then has the burden of production to show that (i) the claimed range is “critical,” meaning that it produces an unexpected result relative to the prior-art range; (ii) the prior art taught away from the claimed range; (iii) the parameters in question are not “result-effective variables”; or (iv) the prior-art range is so broad that it would not invite routine optimization. If the patentee can present such evidence, “[t]he factfinder then assesses that evidence, along with all other evidence of record, to determine whether a patent challenger has carried its burden of persuasion to prove that the claimed range was obvious.” The Court explained that the Board had erroneously failed to apply this burden-shifting framework.
The Federal Circuit also found that the Board had misapprehended the standard for whether a given parameter is a “result-effective variable.” “Under the applicable standard,” the Court explained, “if the prior art does recognize that the variable affects the relevant property or result, then the variable is result-effective.” Thus, “DuPont needed to show that it was recognized in the prior art, either explicitly or implicitly, that the claimed oxidation reaction was affected by reaction temperature and [pressure].” The prior art need not recognize that temperature and pressure “predictably affected” the reaction, or that the temperature and pressure were “necessarily required” to be in the claimed range to reach the desired result.
Applying the correct obviousness standards to the patent, the Federal Circuit held that the challenged claims would have been obvious and thus reversed the Board’s decision. According to the Court, DuPont had shown that the reaction conditions claimed in the patent were the result of routine optimization of result-effective variables, and Synvina had failed to present sufficient objective indicia of non-obviousness to overcome DuPont’s prima facie obviousness case.
DuPont confirms the legal standard applicable to overlapping-range obviousness cases and clarifies the proper test for determining whether a prior-art variable is “result-effective.”
