Given Professor Mandel's findings on hindsight and obviousness (see yesterday's post), his studies went beyond empirical analysis and looked at how the Federal Circuit was applying the suggestion test under hindsight conditions. His analysis focused on the suggestion test as a rule of evidence in patent law, which was previously analyzed by Christopher Cotropia here. Is the court's approach "lowering the obviousness bar?" The answer appears to be "no."
Critics of the suggestion test contend that, simply because combining references is not suggested by a prior suggestion, teaching, or motivation, this does not necessarily mean that it was not obvious to combine the references. PHOSITAs, for instance, may not bother to record obvious aspects of ordinary skill in their field, or technological advance may move so rapidly that there is not time to record or publish obvious combinations.
Mandel submits that this contention misses the point:
This line of argument critiquing the suggestion test glosses over or misses critical doctrine concerning the suggestion requirement. Under Federal Circuit case law, a decision-maker may rely on an implicit suggestion or motivation to combine prior art references—the suggestion or motivation does not need to be recorded or documented. Federal Circuit precedent provides two implicit bases, the "nature of the problem to be solved" and the "knowledge of persons of ordinary skill in the art," as acceptable bases for combining prior art in the non-obvious analysis. A decision-maker can depend on these criteria, therefore, to identify motivations for combination that no PHOSITA has bothered to record or document, either because the combination seems basic, because technological advance is occurring rapidly, or for some other reason. The Federal Circuit recently confirmed that a suggestion may be implicit: "A suggestion, teaching, or motivation to combine the relevant prior art teachings does not have to be found explicitly in the prior art." (In re Kahn, Ruiz v. Chance)Another line of criticism is that the suggestion test is appropriate, but is applied improperly by the Federal Circuit, particularly when suggestions from the nature of the problem to be solved, or the knowledge of a PHOSITA, are purportedly ignored. However, a review of Federal Circuit non-obvious decisions suggests that the court rarely engages in such conduct.
In almost all non-obvious opinions, the Federal Circuit explicitly identifies the nature of the problem and knowledge of a PHOSITA as potential sources for finding a suggestion to combine references. Cotropia's study (see above) of all reported Federal Circuit non-obvious decisions over a recent three-year period found many cases in which the Circuit actually relied on one of implicit forms of suggestion or motivation.
In the few cases in which the Circuit appeared to ignore the potential implicit potential evidence in applying suggestion test, Cotropia concluded that the Circuit was actually simply applying a rule of evidence to exclude unreliable suggestion evidence, such as mere conclusory statements that a given combination was obvious. Over the last three years, only four non-obvious cases decided by the Federal Circuit appeared to ignore implicit evidence of a suggestion to combine references. One of those four was KSR v. Teleflex.
Thus, while bifurcating obviousness appears to have the greatest effect on mitigating hindsight, Mandel argues that the suggestion test should be retained as a "second-best" option:
The hindsight bias thus remains unresolved in current patent jurisprudence. It is appropriate, therefore, to repeat a call to bifurcate the non-obvious issue whenever possible—this remains the only means identified to eliminate the hindsight bias in patent decisions . . . Bifurcation is the only means identified to achieve non-obvious decisions that comport with the non-obvious requirement enacted in the Patent Act and developed in Supreme Court precedent.
For circumstances in which the non-obvious issue cannot be bifurcated (most significantly, cases tried to judges), the suggestion, teaching, or motivation test remains a legitimate second-best option. The results reported here indicate that the suggestion test does not distort non-obvious decisions in the manner claimed by critics. In addition, as discussed below, the test may help mitigate the hindsight bias for certain types of invention that would not have been identified in these studies (e.g., complex technology inventions). As the hindsight bias is known to substantially prejudice non-obvious decisions, the suggestion test should be retained because the problem it confronts (erroneous decisions that an invention is obvious in hindsight) is known and significant, while the problem the test is alleged to create (over-compensation for the hindsight bias) is unconfirmed and conjectural.