In re Peterson

In re Peterson[1]

In re Peterson involved an appeal from the USPTO Board of Appeals with respect to the patentability of the claims of a pending US patent application. The primary issue in this case was on the determination of obviousness. The claim in suit related to a nickel base superalloy consisting essentially of 1 – 3% Rh about 14% Cr and specified amounts of other elements. The examiner asserted a case of prima facie obviousness based on over lapping ranges in prior art references. The applicant argued that no one would have chosen his particular rhenium content and argued that this produced unexpected properties.

The court dealt first with the question of prima facie obviousness in this type of situation, stating:

“Selecting a narrow range from within a somewhat broader range disclosed in a prior art reference is no less obvious than identifying a range that simply overlaps a disclosed range. In fact, when, as here, the claimed ranges are completely encompassed by the prior art, the conclusion is even more compelling than in cases of mere overlap. The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages. See In re Boesch, 617 F.2d 272, 276, 205 USPQ 215, 219 (CCPA 1980) (“[D]iscovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art.” (citations omitted)). We therefore conclude that a prior art reference that discloses a range encompassing a somewhat narrower claimed range is sufficient to establish a prima facie case of obviousness. That is not to say that the claimed composition having a narrower range is unpatentable. Rather, the existence of overlapping or encompassing ranges shifts the burden to the applicant to show that his invention would not have been obvious…”

In cases where a narrow numerical range is selected from a broader prior art range, at least when dealing with multi-component compositions of matter, even a slight overlap will result in a prima facie case. Indeed this may occur even without overlap because there is a normal tendency of those skilled in the art to improve on what is generically known establishes a prima facie case of obviousness. This can be overcome by showing the narrower range claimed later to be critical, for example by showing unexpected results throughout the narrow range when compared with the generality of the broader range. An alternative way to overcome the prima facie case would be to show that the prior art teaches away from the invention in some material respect. In the present case, however, the examples were held not to support any criticality and the prior art, despite some teaching that too high a chromium level could be catastrophic, did not point away.
[1] 65 USPQ2d 1379 (Fed. Cir. 2003).