Obviousness rejections are (at least for now) the bread and butter of examiner rejections. While a few years old now, the research of Frakes and Wasserman put the numbers as follows: 10 percent for lack of patentable subject matter or utility, 56 percent for lack of novelty, 72 percent for obviousness; and 36 percent for failure to meet the disclosure requirements. Patently-O has some 2017 data that puts the numbers at about 79% for obviousness, and 35% for novelty for that year.

But while examiners make many obviousness rejections, there is also a wide range in how examiners formulate those rejections. This is due, in part, to the many different aspects of the law of obviousness - design choice, obvious to try, motivation to combine, expectation of success, hindsight reasoning, and more.

One style of an obviousness rejection starts with a primary reference and then combines features from a secondary reference because doing so provides some sort of advantageous operation. For example, an examiner might assert that the primary reference suffers from some sort of problem which is allegedly solved by features of the secondary reference. However, even though this may seem like the most traditional way to form an obviousness rejection, often examiners cite a problem the primary reference already has solved. In this case, an applicant can attack the foundation of the rejection by noting that when the prior art already solves the problem the examiner alleges is the basis for adding a secondary feature, there is insufficient support for the rejection.

A recent PTAB case illustrates the issue US Application 14/376,426 to Siemens. The application relates to a method for avoiding pump surges in a compressor where vibration of the housing is utilized to predicatively react to or avoid compressor surge. The examiner rejected claim 14 as obvious. Here, the examiner confirmed that the prior art showed the claimed features, except did not utilize the vibration of the housing. For this, the examiner turned to a secondary reference and alleged it would be obvious to do as claimed (using the housing vibration as compared with other component vibration of the pump) since doing so would “avoid damage to the system.”

The problem for the examiner was that the primary reference already avoided damage to the system by monitoring a component other than the housing. The PTAB thus agreed with the applicant that the primary reference already performed the goal of avoiding damage to the system adequately. From the opinion (internal citations omitted):

More specifically, [the primary reference] discloses a method for detecting compressor stall and surge including, inter alia, monitoring a compressor parameter, such as force and vibrations acting on a compressor casing, analyzing the monitored parameter, comparing the analyzed compressor parameter with a predetermined baseline, and taking corrective action to prevent compressor damage. The Examiner has not provided any findings or an adequate reasoning establishing a problem with [the primary reference’s] method for detecting compressor stall and surge to prevent compressor damage. Without a persuasive articulated reasoning based on rational underpinnings for modifying the method of [the primary reference], according to [the secondary reference], the Examiner’s rejection appears to be the result of hindsight analysis.

So, even though examiners make more Section 103 rejections than anything else does not mean that such rejections are always well founded. Where the examiner alleges a motivation to combine/modify that only addresses an issue already solved by the reference itself, the examiner has not established a proper combination.