Many analyses of obviousness begin with the statutory presumption of validity. A host of CAFC cases provide some treatment about whether or not the art was before, or considered by, the Examiner, and how that affects the presumption. The general view was that the presumption is strengthened when only art considered by the Examiner is asserted, and is not diminished when art not considered is asserted as the grounds for invalidity. Now, reviews of the KSR ruling suggest that it ‘weakens’ existing patents, but that later-issued patents presumptively will be more difficult to invalidate.
That provoked the question, if the file history shows an obviousness rejection based on reference A & B, which was overcome with an argument about no express motivation or suggestion to combine A & B, then what presumption of validity attaches to that patent. Seemingly, an obviousness challenge could be mounted based, a second time, on references A & B. If the examiner ‘rigidly’ accepted the fact that no TSM could be shown in the cited references, then the challenger should face no strengthened presumption as to validity over those same references.
The old rule, now in question for patents issued pre-KSR , as stated in Ultra-Tex v. Hill Bros., 204 F.3d 1360 (Fed. Cir. 2000) was explained that when a party alleges that a claim is invalid based on the very same references that were before the examiner when the claim was allowed, that party assumes the following additional burden:
When no prior art other than that which was considered by the PTO examiner is relied on by the attacker, he has the added burden of overcoming the deference that is due to a qualified government agency presumed to have properly done its job, which includes one or more examiners who are assumed to have some expertise in interpreting the references and to be familiar from their work with the level of skill in the art and whose duty it is to issue only valid patents.
There may be no “added burden” on a challenger for patents issued after an obviousness rejection related to teaching, motivation or suggestion.
The related question concerns whether KSR diminished the presumption when un-cited art is presented as grounds for obviousness. The KSR opinion suggests that the Asano patent, found to be the invalidating reference, was not cited to the Examiner. It’s that next line in the opinion that bears mention: We need not reach the question whether the failure to disclose Asano during the prosecution of Engelgau voids the presumption of validity given to issued patents, for claim 4 is obvious despite the presumption. We nevertheless think it appropriate to note that the rationale underlying the presumption–that the PTO, in its expertise, has approved the claim–seems much diminished here.
So, if you are keeping score, the tally is no “added burden” to overcome, and a “much diminished” presumption that a duly-issued patent is valid.
All this talk of a “presumption,” whether added or diminished, has to intersect with evidential considerations, and issues of fact and law. Presumptions allocate the burdens of going forward, or of proof, or of persuasion – all in all, issues of fact. Indeed, earlier CAFC precedent holds that: Determining whether there is a suggestion or motivation to modify a prior art reference is one aspect of determining the scope and content of the prior art, a fact question subsidiary to the ultimate conclusion of obviousness. Sibia Neuro., Inc. v. Cadus Pharm., Corp., 225 F.3d 1349 (Fed. Cir. 2000). What then is the standard of review for the new, non-rigid standard expressed in KSR, review of a factual determination for clear error, or a legal question reviewed de novo? No fair read of KSR suggests that a clearly erroneous standard of review was applied.