A recent Federal Circuit decision provides a new reminder about the importance in how ranges are addressed in patent applications. In a decision issued March 27, 2018 (In re Brandt), the Federal Circuit held that abutting ranges can establish a prima facie case of obviousness even where the two ranges do not literally overlap.
The application in question, U.S. Application No. 13/652,858 in the name of Brandt (“Brandt”) claimed a covered roof including a roof deck, insulation board and a coverboard in which the coverboard was required to have a density of greater than 2.5 pounds per cubic foot and less than 6 pounds per cubic foot.
The Examiner applied prior art disclosing a polymeric coverboard with a density between 6 pounds and 25 pounds per cubic foot. While acknowledging that the prior art did not specifically disclose a density less than 6 pounds per cubic foot as claimed, the Examiner determined that explicit overlap was not required. Rather, the Examiner determined that in light of expected variations in density as well as other prior art, it would have been an obvious design choice to use a density of less than 6 pounds per cubic foot. Brandt argued the Examiner had not made out a prima facie case of obviousness, and thus it remained the Examiner’s burden the claim was not patentable, because the ranges abutted, but did not actually overlap.
The Patent Trial and Appeal Board (“PTAB”) affirmed the Examiner’s rejection, finding that while not overlapping, the difference between the ranges was “virtually negligible” and “could not be smaller.” As a result, the prior art was still sufficient to establish a prima facie case of obviousness.
The Federal Circuit agreed. The Federal Circuit noted that it might be improper to establish a per se rule that adjacent, but not explicitly overlapping or touching, ranges supports a prima facie case of obviousness. However, the Federal Circuit held that, as in the present case, a factual determination identifying virtually negligible differences in light of expected tolerance levels is appropriate and sufficient to establish a prima facie case. Further, the Federal Circuit criticized Brandt, who had failed to submit any evidence of unexpected results or criticality and relied solely on legal argument. The Federal Circuit was similarly unimpressed by arguments of “teaching away” that relied on purported logical inferences, but which did not meet the standard of criticizing, discrediting, or otherwise discouraging the claimed solution.
This case perhaps does not expand the scope of ranges taught in the prior art for obviousness purposes so much as it forms an expanded scope which had previously been hinted at, however it nonetheless raises several important points for patent application drafting.
First, thoroughly prepared nested ranges are highly recommended. The present result might have been avoided by including as nested range such as “greater than 2.5 pounds per cubic foot and less than 6 pounds per cubic foot, alternatively 2.6 pounds per cubic foot to 5.9 pounds per cubic foot, alternatively 2.75 pounds per cubic foot to 5.75 pounds per cubic foot” or the like. Second, it is important to dig in with inventors to establish a clear understanding of the inventor’s basis (including tolerances and commercial embodiments) for choosing the outer bounds of ranges. Third, where a range is expected to be important, ensuring that the inventors properly establish the endpoints of a range with experimentation, or at least a clear line of technical reasoning, which can be included in the specification or substantiated in a future declaration, is very desirable.
