In KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 421 (2007), the Supreme Court stated that “common sense” can be considered in reaching a conclusion that a claimed invention is obvious. Since then, both litigants and patent examiners have often attempted to cite to common sense as a justification in combining two or prior art references. The Federal Circuit, however, has repeatedly explained that obviousness findings grounded in “common sense” must contain “explicit and clear reasoning providing some rational underpinning why common sense compels a finding of obviousness.” In re Van Os, 844 F.3d 1359, 1361 (Fed. Cir. 2017) (internal citations omitted). Common sense “cannot be used as a wholesale substitute for reasoned analysis and evidentiary support.” Arendi S.A.R.L. v. Apple Inc., 832 F.3d 1355, 1362 (Fed. Cir. 2016).

The recent final written decision in Kranos Corporation v. Riddell, Inc., Case IPR2016-01649, Paper 25 (Feb. 7, 2018) sheds light on how the PTAB may treat common sense as used in obviousness arguments. The claimed invention was a sports helmet (e.g., a football helmet) with a quick release connector for the faceguard. An important claim element was the “releasable coupler mechanism.” During prosecution, the applicant had distinguished the claimed invention from conventional football helmets, which utilized a threaded fastener for the faceguard to be rotatably attached or detached with a screwdriver. Based upon the intrinsic evidence, the PTAB construed a “releasable coupler mechanism” as a coupler mechanism that does not employ a threaded connector, such as a screw, that is rotated to attach or detach a component.

The Petitioner argued certain claims were unpatentable over the combination of the Ide and Szendel references. Ide discloses a football helmet with a nut and bolt connector for connecting the faceguard. However, because the nut and bolt connector is “rotatably threaded and rotated,” the PTAB found it to be a conventional faceguard connector and not the “releasable coupler mechanism” claimed in the patented invention. Szendel, on the other hand, discloses a quick-release type axle system for in-line roller skates. The system of Szendel utilizes two axle shafts with release pin with a bearing spacer to lock the wheels of the in-line skates from their frame. When the release pin is pulled outwardly, the axle shaft is withdrawn from the bearing spacer and the wheel assembly can be removed from the frame.

During the proceeding, Petitioner argued it was “common sense” to integrate the unthreaded coupling mechanism of Szendel with the coupling mechanism of Ide. Petitioner’s expert testified that the Szendel unthreaded mechanism was a “known alternative” to a threaded nut and bolt mechanism. Ultimately, however, the PTAB rejected Petitioner’s argument to combine references. Common sense, it noted, is a conclusory label, and it should be the conclusion reached after being presented with a reasoned analysis. As such, the PTAB found that Petitioner’s failure to explain the common sense on which it relied was problematic. Even though Szendel stated that its disclosed system “is intended as an improvement to nut and bolt fasteners that use screwdrivers and wrenches,” the PTAB found that Petitioner had failed to address details such as why the football helmet of Ide would need the bearing spacer of Szendel, or why it would need only one axle from Szendel, instead of two axles. Petitioner, according to the PTAB, failed to identify why a person would have selectively gleaned some elements or structure from the references relied upon to come up with the limitations in the challenged claims. As such, the PTAB found that Petitioner had failed to provide persuasive evidence as to why a person of ordinary skill in the art would have substituted the system in Szendel for the threaded connector in Ide.

Finally, the PTAB cautioned against the danger of hindsight bias. As the PTAB explained, “taken out of a specific context, providing an unthreaded connector or washer in the Ide system may seem like a simple, common sense modification.” However, the PTAB continued, “in the highly developed field of sports helmets and quick-release connectors, small differences may produce a nonobvious advance.”

The Kranos decision teaches Petitioners to avoid relying only upon “common sense” as a reason for combining references. Rather, an effective Petition should lead the PTAB to conclude that “common sense” supports obviousness, after presenting the PTAB with a persuasive showing of why the elements or structure of one reference should be combined with those of another.