The issue of obviousness is at the heart of defining what is, and what is not, an invention. While examples at the extremes are relatively easy to find, many cases tend to lie somewhere in the fuzzy range between obvious non-patentable concepts and non-obvious inventions. Finding and presenting convincing arguments, one way or the other, is part of the challenge that makes patent law so engaging.

A particularly flexible area of obviousness relates to the issue of making a particular combination of references in order to reach a claimed invention.  Often, a first reference shows most of the claimed elements, and a second reference is added to show a missing feature. One common approach to arguing against obviousness is to focus in on the teachings of each reference and explain why the combination does not make sense, or can only be explained based on hindsight. While this can often be a successful approach, a significant weakness is that any alternatives listed in the reference can be used to pick apart an otherwise strong and convincing argument. Another area of obviousness that is generally more clear is that once the combination is made, all of the limitations must actually be present.

An example of the first issue is illustrated in US 12/430,389, a GM patent application directed toward gesture-based navigation systems. Claim 1 sets forth:

The issue in this case was that the primary reference (a cell phone based gesturing system where one points with the cell phone at a point of interest to obtain information about that point of interest) failed to utilize any camera based gesture capture. A secondary reference was relied upon for this missing element, the secondary reference teaching a cell phone using its camera to capture images for controlling another device, such as a TV. The Applicant's argument against obviousness was that the combination made no sense because the whole point of the primary reference was to rely on the pointing of the mobile device itself to generate motion to identify a pointing direction. While at first blush this seems like a convincing argument, on appeal the PTAB discounted the argument. The reason was that the specification of the primary reference included a little broadening language that there could be other ways to identify the pointing direction, such as using input keys on the mobile phone. Because the Applicant had not addressed these alternatives in their brief, it was easy for the Board to discount the thrust of Applicant's argument and affirm the rejection.

Another example of the perils of obviousness arguments is US 12/582,142, a Bosch patent application related to display of a navigation map. Claim 1 recites:

Here, an issue in the case was whether the cited reference taught the limitation of modifying the viewing angle ... based on feedback from the user. The Examiner relied on prior art where movement of the vehicle changed the vehicle angle, and the viewing angle changed based on the vehicle's position. The Applicant pointed out that changing the moving direction of the vehicle is not feedback from the user, but rather changing the actual camera direction. Thus, here the Applicant was not relying on an argument against the combination itself, but rather pointing out that even if the combination was made, a claim element was still missing. As noted above, this aspect of obviousness is generally more clearly defined, in that the reference must actually teach the missing element. However, folding in the Broadest Reasonable Interpretation, the PTAB often bends over backwards to find a way to support a rejection and did so here.

In particular, while one might reasonable understand that the modification of the viewing angle based on feedback from the user means that there must actually be some user interaction related to the display on the navigation map (see the preamble of claim 1), the PTAB determined that the user driving the vehicle was sufficient "feedback from the user" because the user drives the vehicle.  From the PTAB's decision:

While this reasoning is somewhat dubious, it illustrates that the pitfalls in obviousness arguments at every turn.