In the opinion, the Court articulated several guidelines for helping determine obviousness. First, "[t]he combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results." Second, "[w]hen a work is available in one field of endeavor, 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, [obviousness] likely bars its patentability." Third, "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." Fourth, the Court concluded that "a court must ask whether the improvement is more than the predictable use of prior art elements according to their established functions." In short, the court's "analysis need not seek out precise teachings directed to the specific subject matter of the challenged claim, for a court can take account of the inferences and creative steps that a person of ordinary skill in the art would employ."

Which, if any of these, applies to 336? Worth reflecting on. Opty