BPAI: when prior art teaches away, expectation of success cannot support obviousness rejectionAugust 16, 2008

In a recent precedential decision by the Board of Patent Appeals and Interferences, the board reversed an Examiner's rejections based on double patenting, anticipation, and obviousness. The Board held the Examiner inappropriately rejected the claims for double patenting because there was insufficient evidence to show the compositions claimed in the prior art possessed the viscosity level claimed in the current application or that they would be obvious variants. The Board similarly reversed the anticipation and obviousness rejections. The Board noted the Examiner did not provide "an adequate basis – based on evidence or scientific reasoning – to support" the argument that the prior art compounds inherently met the viscosity limitation. Further, the examiner's logic that the compounds were obvious based on the motivation in the art to optimize the viscosity of the prior art formulations was also rejected. The Board noted that though "the discovery of an optimum value of a variable in a known process is normally obvious," here the cited references all indicated that low viscosity, not the claimed high viscosity, was desirable. In fact, the Board, citing KSR, highlighted that there still must be a reason to make the asserted modifications to the prior art. This is particularly the case when the prior art teaches away:

[W]hen the prior art teaches away from the claimed solution as presented here, obviousness cannot be proven merely by showing that a known composition could have been modified by routine experimentation or solely on the expectation of success; it must be shown that those of ordinary skill in the art would have had some apparent reason to modify the known composition in a way that would result in the claimed composition.

More on Ex parte Whalen after the jump.The Application at issue related to a compound used to embolize an aneurysm at or near the injection site, by using a "biocompatible polymer, a biocompatible solvent and a contrast agent." Of most relevance to the appeal, one of the claim limitations in all pending claims required the compound to have a viscosity of "at least 150 cSt at 40°C."The Examiner rejected the claims under the doctrine of obviousness-type double patenting over four prior art patents (note that one, 5,851,508 is incorrectly listed as 5,581,508 in the decision). Two of these patents were used for § 103 rejections. The Examiner also issued a § 102(b)/§ 103 rejection in view of a journal article authored by Taki.The Board began its discussion by examining the rejection based on obviousness-type double patenting. The Examiner argued "it would have been obvious to one of ordinary skill in the art at the time of the invention to practice the pending claims when in possession of the patented claims." The Board disagreed, concluding the Examiner had not produced any reasons or "fact-based explanations" to warrant a double-patenting and therefore reversed that rejection. Specifically, there was no evidence that any of the claimed compounds in the prior art would meet the viscosity limitation in the current application. There was likewise no reason to conclude the claims on appeal were obvious in light of the patented claims.The Board then moved to the § 102(b) rejection. The Examiner argued the prior art taught the same viscosity because they "comprise similar components used in overlapping ranges of concentrations as those claimed." After thoroughly examining the prior art, the Board held there was no anticipation. The Board quoted the familiar passage from In re Oelrich that "[i]nherency…may not be established by probabilities or possibilities. The mere fact that a certain thing may result from a given set of circumstances is not sufficient." Here, there was no "evidence or scientific reasoning to show that any specific composition disclosed by [the prior art] is within the scope of the instant claims," and as a result, there could not be anticipation by inherency.Regarding the § 103 rejections, the Examiner argued even if the claims were not anticipated, it would have been obvious to optimize the viscosity outlined by the prior art. The Board once again did not agree. While normally the finding of an optimum value of a variable in a known process is obvious, here, the prior art all taught the usage of a low viscosity material as the desired component, but the Application claimed the exact opposite: high viscosity. The Board then applied the test for obviousness outlined in KSR Int'l Co. v. Teleflex Inc. In obviousness rejections, KSR requires that one of ordinary skill in the art must be motivated to combine the elements of the prior art; it is not sufficient that just the elements were present. As described by the Board:

In the same way, when the prior art teaches away from the claimed solution as presented here, obviousness cannot be proven merely by showing that a known composition could have been modified by routine experimentation or solely on the expectation of success; it must be shown that those of ordinary skill in the art would have had some apparent reason to modify the known composition in a way that would result in the claimed composition.

There was no such apparent reason here. Thus, all rejections were reversed.To read the full decision in Ex parte Whalen, click here.Hat tip to Peter Zura for noticing the decision.

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