Defending against an obviousness attack at the PTAB or rejection by a USPTO examiner can be tricky.  The Supreme Court in KSR v. Teleflex (2007) identified a number of rationales (seven) to support a conclusion of obviousness. Most rationales invoke the notion of predictability for the results yielded by the combination of prior art references.  The challenger gets to pick and choose the rationale that fits best the claimed invention and the prior art.

The trick for the patent applicant or owner is to find the right tool within the non-obviousness toolkit to defend against the challenge.  It turns out that one such tool is an older decision, still being applied today.  The case is In re Ratti (CCPA 1959).  It stands for the proposition that, if the proposed modification or combination of the prior art would change the principle of operation of the prior art invention being modified, then the teachings of the references are not sufficient to render the claims prima facie obvious. In its decision, the Court reversed the obviousness rejection, holding that the "suggested combination of references would require a substantial reconstruction and redesign of the elements shown in" the primary reference.

It may be surprising that this case is still relied upon by the USPTO (e.g., MPEP 2143.01-VI).  This pre-KSR case does not discuss the question of predictability.  Further, the KSR decision did not apply the In re Ratti rationale.  The claimed invention in KSR was an adjustable pedal with an electronic pedal-position sensor attached to a fixed pivot point.  A primary prior art reference (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control.  The secondary prior art reference disclosed an electronic pedal sensor was placed on a pivot point.  The Court agreed with the accused infringer that it would have been obvious to modify the Asano system from a mechanically controlled throttle to an electronically controlled throttle.  On one hand, one could argue that such a modification would change the principle of operation of the Asano pedal, and require a substantial reconstruction and redesign of the Asano pedal.  On the other hand, one could try to reconcile KSR with In re Ratti by redefining the principle of operation of the Asano reference to better align it with the modification.

In any event, the USPTO is relying on In re Ratti to uphold the non-obviousness of inventions, especially at the PTAB.  For example, the PTAB recently cited to it in Microsoft v. Philips (PTAB, May 22, 2018) when denying a petition for Inter Partes Review challenging claims directed to a handheld communication device with an auto-zoom feature.  The claims recited a system "operative to enable the user to select through a touch location on the touch screen a portion of the image, when displayed at a first scale, for rendering the selected portion on the display at a second scale larger than the first scale thereby facilitating a selection of a feature, and the selected portion when rendered at the second scale is a zoomed-in version of part of the image at the first scale substantially centered around the touch location."  The primary reference (Murase) disclosed an auto-zoom feature that automatically enlarges an image based on a user's finger or stylus approach of the screen, i.e., not based on touch.  If the user then touches the screen, the Murase system identifies an input based on the user's selection with respect the enlarged display screen.  The secondary reference (Heikkinen) disclosed a mobile station with touch sensitive input to magnify an area, followed by another touch for selection.  The PTAB rejected the obviousness argument stating:

We are also persuaded that the proffered combination of Murase and Heikkinen would change the "basic principles under which the [prior art] was designed to operate." In re Ratti, 270 F.2d 810, 813 (C.C.P.A. 1959). Replacing a system that that allows for identification and selection upon touch, i.e., Murase, with a system of protracted touch with magnification and selection, i.e., Heikkinen, would change the manner that the system in Murase was designed to operate. For this additional reason, we are not persuaded by Petitioner that one of ordinary skill in the art would have been motivated to combine the teachings of Murase and Heikkinen as suggested by Petitioner.

In this case, the PTAB did not consider whether the proposed modification of the Murase system would have yielded predictable results, nor did it even cite KSR.  In our own practice, we've seen the PTAB reverse obviousness rejections and rely on In re Ratti.  This older decision is thus still a useful tool for applicants and patent owners in certain situations.

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