Patently Non-Obvious II: Experimental Study on the Hindsight Issue Before the Supreme Court in KSR v. Teleflex

43 Pages Posted: 6 Sep 2006 Last revised: 26 May 2016

See all articles by Gregory N. Mandel

Gregory N. Mandel

Temple University - James E. Beasley School of Law

Date Written: 2007


For the first time in thirty years, the Supreme Court will consider the core patent requirement that an invention be non-obvious. At the heart of the case lies the challenge of how to insulate non-obvious decisions from the distortion of the hindsight bias. This Article reports the latest empirical studies in a line of hindsight research, which present experimental data bearing directly on the issue before the Court: how individuals make non-obvious decisions under existing Supreme Court and Federal Circuit precedent.

The study results indicate that the Federal Circuit's suggestion, teaching, or motivation requirement, the precedent challenged before the Supreme Court in KSR v. Teleflex, does not produce erroneous non-obvious outcomes. This result contradicts the claims of the petitioners in KSR and other critics of the suggestion requirement. On the other hand, the results do not demonstrate that the suggestion test ameliorates the hindsight bias in the manner usually claimed by its supporters. An additional study indicates that the Supreme Court's Graham framework does not resolve the hindsight problem either. Given the substantial and confirmed prejudicial effect of the hindsight bias, the Article concludes that the suggestion test should be retained for several reasons: it does not appear to cause the harms hypothesized by its critics, it potentially reduces the hindsight bias for complex technology inventions, and the problem the test 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.

The Article concludes with a recommendation for bifurcating the non-obvious decision at the Patent and Trademark Office. Combined with an earlier proposal for jury trials, these recommendations present the only known means for eliminating the hindsight effect and producing patent decisions that comport with the Patent Act and Supreme Court precedent.

Keywords: nonobvious, non-obvious, patent, obvious, hindsight, bias, suggestion, Graham, bifurcate

JEL Classification: K30, K40, K41

Suggested Citation

Mandel, Gregory, Patently Non-Obvious II: Experimental Study on the Hindsight Issue Before the Supreme Court in KSR v. Teleflex (2007). Yale Journal of Law & Technology, Vol. 9, No. 1, 2007, Available at SSRN: or

Gregory Mandel (Contact Author)

Temple University - James E. Beasley School of Law ( email )

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