On April 30, 2007, the Supreme Court decided KSR International Co. v. Teleflex, Inc., an important decision regarding the statutory standard for determining whether a patent is obvious within the meaning of 35 U.S.C. § 103.1 The patent at issue consisted of several components that were known in the prior art, but which had been combined and patented as a new invention. The Federal Circuit had held there was no sufficiently specific evidence of a teaching, suggestion, or motivation (TSM) to combine the elements. The Supreme Court unanimously overruled that decision, concluding that the Federal Circuit’s application of the TSM test was too rigid. Considering the patent in light of the Court’s precedent and the text of the Patent Act, the Court determined that the combination of prior art reflected in the patent would have been obvious to a person having ordinary skill in the art (PHOSITA). Thus, the Court held that the patent was obvious and unpatentable.

The Court’s decision in KSR did not abandon the TSM test—an approach pressed by some of the patent system’s critics. Nevertheless, it is still likely that KSR will impact the initial determination of whether an invention is patentable, not to mention the ability of those accused of infringement to challenge a patent’s validity during litigation.


Along with utility and novelty, the non-obviousness requirement found in Section 103 of the Patent Act is one of three statutory conditions for patentability.2 Under Section 103, an invention is not patentable if, from the perspective of “a person having ordinary skill in the art,” the “differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made.” Generally speaking, if it is easy to show that an invention is obvious, it will be much harder to obtain and defend a patent.

The reverse is also true: the harder it is to show that an invention is obvious, the easier it will be to obtain and defend a patent.

In light of the importance of the non-obviousness requirement to determining patentability, the Supreme Court has adopted a flexible framework for determining when an invention is obvious within the meaning of Section 103. Thus, in Graham v. John Deere Co., the Court explained that obviousness is a question of law that lends itself to several factual inquiries, including the scope and content of the prior art; the differences between prior art and the claims at issue; and the level of ordinary skill in the pertinent art.3 Graham also identified several secondary considerations that “may have relevancy,” including commercial success, long felt but unsolved needs, and failure of others.4 The Court has adhered to this “practical” interpretation of Section 103 in subsequent cases.5

The Teaching, Suggestion, or Motivation Test and KSR

The Federal Circuit has implemented the obviousness requirement and the Supreme Court’s decision in Graham by way of the TSM test. According to the Federal Circuit, when an invention is comprised of multiple prior art references, whether the invention is obvious depends on specific evidence that the prior art provided a teaching, suggestion, or motivation to combine the prior art.6 The motivation to combine can be explicit, implicit, or even inferred from the “nature of the problem to be solved,” the Federal Circuit has explained, but it must be present in some form in order to maintain a finding of obviousness.7

The facts in KSR presented a classic obviousness question. The patent at issue, United States Patent No. 6,237,565 (the ‘565 patent), revealed a gas pedal assembly that combined two pieces of technology within the prior art: electronic sensors on gas pedals used to regulate a vehicle’s throttle and gas pedals that adjust to accommodate drivers who are taller or shorter than average. Applying Graham, the district court concluded that the assembly was unpatentable because all of the elements of the patent claim were included in the prior art and a person having ordinary skill in the art—someone with training in mechanical engineering and experience in the field of pedal assemblies—could easily combine an adjustable gas pedal with an electronic sensor. The district court also reasoned that summary judgment was appropriate because a person with skill in the art actually would have been motivated to make the combination.

The Federal Circuit reversed on the ground that the district court incorrectly applied the TSM test. According to the Federal Circuit, the district court had not made required factual findings showing the “specific understanding or principle within the knowledge of the skilled artisan that would have motivated one with no knowledge of [the] invention to make the combination” in “the particular July 2007 | 3 manner claimed by” the patent.8 In other words, the district court could not find the patent invalid as obvious without “specific findings as to a suggestion or motivation to attach an electronic control to the support bracket of the [gas pedal] assembly.”9

The Supreme Court granted KSR’s petition for certiorari on June 26, 2006. The Court heard oral argument on November 28, 2006, and handed down its decision on April 30, 2007. The Supreme Court Rejects the “Rigid” Application of the TSM Test in KSR Reversing the Federal Circuit’s decision, the Supreme Court “reject[ed] the rigid approach of the Court of Appeals” but stopped well short of abandoning the TSM test.10 To the contrary, the Court underscored that its precedent “set forth an expansive and flexible approach inconsistent with the way the Court of Appeals applied its TSM test here.”11 The Court underscored that because the process of invention is fluid, the obviousness inquiry must not be artificially constrained. “When a work is available in one field of endeavor,” Justice Kennedy wrote, “design incentives and other market forces can prompt variations of it, either in the same field or a different one. If a person of ordinary skill can implement a predictable variation, § 103 likely bars its patentability. For the same reason, if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious unless its actual application is beyond his or her skill.”12 Thus, in assessing whether it would have been obvious for a person to combine prior art elements, Justice Kennedy reasoned that courts should take a number of factors into account, including “interrelated teachings of multiple patents; the effects of demands known to the design community or present in the marketplace; and the background knowledge possessed by a person having ordinary skill in the art.”13

Turning to the Federal Circuit’s TSM test, the Court held that it captured a “[h]elpful insight” regarding obviousness, but that it was “incompatible with [the Court’s] precedents” when applied in a “rigid” fashion or as a “mandatory formula[ ].”14 To be sure, the Court emphasized, “[t]here is no necessary inconsistency between the idea underlying the TSM test and the Graham analysis. But when a court transforms the general principle into a rigid rule that limits the obviousness inquiry, as the Court of Appeals did here, it errs.”15

The Court next addressed several specific flaws in the Federal Circuit’s analysis and application of the TSM test. First, Justice Kennedy wrote that in determining whether the ‘565 patent was obvious, the Federal Circuit did not properly consider whether “there existed at the time of the invention a known problem for which there was an obvious solution encompassed by the patent’s claims.”16 Rather, the Federal Circuit “foreclosed this reasoning by holding that courts and patent examiners should look only to the problem the patentee was trying to solve.”17

Second, the Court explained that the Federal Circuit erroneously assumed that in attempting to solve a problem a person having ordinary skill in the art (again, a PHOSITA) “will be led only to those elements of prior art designed to solve the same problem.”18 In fact, courts and examiners should adopt a more nuanced, and commonsense approach to understanding how PHOSITA will fit together multiple patents to solve a new problem.19 “A person of ordinary skill is also a person of ordinary creativity,” the Court emphasized, “not an automaton.”20

Third, the Court noted that the Federal Circuit was properly concerned with the prospect of hindsight bias but that it drew the “wrong conclusion” from those concerns.21 In particular, factfinders “should be aware . . . of the distortion caused by hindsight bias and must be cautious of arguments reliant upon ex post reasoning,” but that “[r]igid preventative rules that deny factfinders recourse to common sense . . . are neither necessary under our case law nor consistent with it.”22 Focusing on these shortcomings in the Federal Circuit’s decision, the Court did not cast aside the TSM test in its entirety. Indeed, it noted that the Federal Circuit “has since elaborated a broader conception of the TSM test than was applied in the instant matter,” but observed that “[t]hose decisions . . . are not now before us and do not correct the errors of law made by the Court of Appeals in this case.”23 The Court therefore left it to the Federal Circuit to consider whether those cases “may describe an analysis more consistent with our earlier precedents and our decision here.”24

Then, specifically addressing the ‘565 patent, the Court agreed with petitioners’ contention that it was obvious within the meaning of Section 103 and therefore invalid.25 The Court agreed that the prior art taught the various components included in the patented adjustable pedal assembly. The Court also identified several pressures in the marketplace that created strong incentives for an inventor to combine the prior art (notably the increase in demand for pick-up trucks and sport utility vehicles which tended to incorporate adjustable pedal assemblies). Finally, the Court found multiple likely routes for PHOSITA to combine the prior art and create the underlying invention.

Implications of KSR v. Teleflex

The Court’s decision reversing the Federal Circuit suggests several important points about the development of patent law. First, it may come as somewhat of a disappointment to certain of the patent system’s critics who advocated for abolition of the TSM test; the Court essentially invited the Federal Circuit to continue to apply the test (albeit with the Court’s guidance going forward). The decision also can be viewed as part of the Court’s recent trend of exercising greater oversight with respect to patent law. Specifically, KSR in implementation will likely result in the rejection and invalidation of at least some patents that would otherwise have been approved and upheld. Patent examiners will likely heed the Court’s reminder that a PHOSITA approaches technical problems in a commonsense manner and may consider prior art from multiple fields. This will make it more difficult to obtain combination patents. And in turn, as a result of KSR, district courts and the Federal Circuit may prove more likely to invalidate (and uphold invalidations of) patents as obvious—and patent litigants more likely to vigorously pursue such challenges.