Inventions must be non-obvious to qualify for patent protection. While there are many ways to argue obviousness, savvy attorneys like to find a way to use "teaching away" by the prior art. Common sense illustrates why - how can the invention be obvious if the prior art says to do the opposite? Further, while the Supreme Court may have raised the bar of non-obviousness in KSR, they explicitly noted that “when the prior art teaches away from combining certain known elements, discovery of a successful means of combining them is more likely to be nonobvious.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398 (2007).

There are limits to teaching away. As an initial matter, the prior art must actually teach away, as opposed to simply not teaching any direction or teaching another direction. For example, teaching that the approach is expensive or wasteful is not enough. However, there is another aspect of teaching away that is often overlooked by Applicants in their zeal to utilize teaching away. That aspect is that the teaching away must actually relate to the parts of a reference that are being used to reach the claimed invention.

Consider the recent decision by the Patent Trial and Appeal Board (PTAB) in SN 11/722,157. The invention related to a wire saw having a circular cross section and crimps in at least two planes. The primary reference showed the circular wire saw, but lacked the crimps in at least two planes. A secondary reference showed a wire for a tire with the two crimps. However, the reference also contained a statement that use of the two crimps would make achieving a rotary torque function (relevant for the tire wire) impossible when using the crimps in different planes if the cross section was circular. The Applicant focused heavily on the teaching away, thinking that the statement of impossibility was about the best one could ever hope for in terms of teaching away. 

The problem here, according to the PTAB, was that the torque function had nothing to do with the features being used by the combination. In other words, the Examiner was only using the crimps in two different planes from the tire wire, not the rotary torque aspects. Therefore, even if achieving the rotary torque function was impossible with a circular cross-section, that did not destroy the combination because there was no teaching not to use crimps in different planes for a wire saw. 

While perhaps there were more persuasive ways to argue against the Examiner's combination, the point here is that the PTAB will use this type of approach wherever possible to discount teaching away arguments. Before using teaching away, make sure that the actual teaching away is relevant to the elements of a reference that are used in the combination. Teaching away from using a features with regard to elements not needed in the proposed combination will typically be an ineffective argument (even if the teaching away from those elements is strong), as illustrated in this case.