Patent examiners often cite a motivation to combine references when rejecting claims under 35 USC Section 103. When an examiner expressly cites motivation that is gleaned only from the applicant’s disclosure, then the examiner uses improper hindsight. But when an examiner creates another reason, albeit most likely using hindsight reasoning, the issue may be better characterized as improper motivation since there is no express reliance on information only from the applicant’s disclosure. A recent PTAB case illustrates the situation.
The case is Appeal 2023-002022, Application 16/302,254. The invention involves a heat and moisture exchanger (HME) that includes a wall comprising a foamed plastic material. Claim 14 on appeal is reproduced below, along with FIG. 2 from the application:
14. A heat and moisture exchange (HME) device comprising a housing providing an inlet coupling, an outlet coupling and a transversely enlarged central region between the inlet and outlet couplings, the device including an HME element retained in the enlarged central region having opposite end faces spaced from respective inner opposing walls of the housing in the enlarged central region of the housing so that air can flow through the element across the entire surface of both faces, characterized in that a wall of the housing at least in the enlarged central region includes foamed plastic material having a thickness adapted to provide thermal insulation of the housing
around the HME element.
The examiner constructed a hypothetical technical problem that did not actually exist in the prior art and used this fabricated problem to justify combining multiple references. The examiner relied on a first reference disclosing an HME (but that was missing the foamed plastic material with the required thickness). To solve this deficiency, the examiner relied on a secondary reference with a breathing tube having the required wall of foamed plastic material. The stated reason to make the combination was that doing so would reduce condensation of humidified gas.
At first glance, the examiner's rationale might seem to fall into the realm of hindsight, which is inherently improper. But as noted above, hindsight requires expressly using the applicant's own disclosures to reconstruct the invention from the cited art. This specific and narrow interpretation of hindsight, limiting it to scenarios where the examiner, for example, expressly cites a problem that only the applicant has recognized, would not apply here. In this case, since the problem was fabricated rather than derived from the applicant's disclosure, it technically does not meet the USPTO’s definition of hindsight.
In this case, the applicant attacked the rejection as being based on improper motivation (even though in all likelihood the examiner was using improper hindsight to form the rejection). Specifically, the applicant pointed out that HME’s allow for condensation of moisture from a user’s breath onto an HME element, and that this condensation is not a problem to be solved but rather merely part of the operation of the HME itself.
The PTAB agreed with the applicant:
Given that the purpose of an HME is, to some extent, to store moisture, it is not immediately apparent that condensation on the wall of an HME presents a disadvantage as the Examiner’s finds. Nor does the Examiner identify any portion of the prior art that supports the finding that prevention of such condensation would assist the function of the HME element. Thus, on the record before us, the Examiner’s finding that “the inclusion of the teachings of Graham into Harwood ensures that moisture from exhalation can be condensed and absorb in the HME element/material as is intended” (Ans. 5) is not supported by a preponderance of the evidence. Accordingly, the Examiner’s reasoning for the proposed modification lacks rational underpinnings.
The examiner's creation of a non-existent problem to rationalize the combination of prior art references thus lacked a legitimate basis. It’s a tactic that diverts from the proper analysis of whether a person of ordinary skill in the art would have been motivated to combine these references based on the existing knowledge and disclosure in the cited references. Practitioners need to be vigilant in identifying such improper motivations and clearly articulating them as such, rather than defaulting to the argument of hindsight (unless the facts specifically support it in the narrow view held by the USPTO/PTAB).