Enablement rejections are less common in the mechanical and electrical arts, but some examiners prefer to make such rejections at higher than normal rates. A recent PTAB decision illustrates how a proper enablement rejection should be formulated, including various requirements on the examiner when addressing the Wands factors. The examiner must evaluate whether there is undue experimentation, which is determined by considering the Wands factors. While the examiner must evaluate undue experimentation via these factors, there is no requirement that the examiner consider every single factor in the determination.

Turning to 14/675,798 (assigned to Whirlpool), it relates to a refrigerator control system, and in particular to a method for actuating a humidifier to provide humidification to an interior of a refrigeration compartment. The method utilized a desired humidity, along with a measured temperature and some other factors to calculate an estimated humidity. The claim recited a particular way to calculate the estimated humidity as follows:

calculating an estimated humidity level for the interior of said refrigeration compartment based, at least in part, on said temperature in the interior of said refrigeration compartment and at least one of said length of time since the last defrost operation, the length of time since the door to said refrigeration compartment was last opened and said compressor time.

The examiner took issue with the disclosure as being non-enabling, mostly attacking the engineering quality level by pointing out that such an estimate would not work and would not be accurate. From the rejection, the examiner explains that “the specification does not describe how exactly this calculation is accomplished, it only describes that the amount of required humidity is a function of said variables, without providing the necessary algorithm or mathematical formula so as to obtain a numerical value for an absolute humidity or a relative humidity.”

While the PTAB clearly liked the Examiner’s engineering focus, they ultimately found that the examiner’s analysis was off the mark and requiring too much:

At the outset, we commend the Examiner for the thorough, detailed, thoughtful, and insightful analysis that went into the Final Rejection and the Examiner’s Answer. The Examiner has demonstrated a clear grasp of the technical issues that are involved in estimating the humidity level inside of a refrigerator without the use of a humidity sensor. Notwithstanding the foregoing, however, the Examiner has applied an incorrect standard of nonenablement to the facts of this case in the following two respects: (1) the performance criteria that is applied to an invention; and (2) the amount of experimentation that is considered to be “undue.”

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In analyzing enablement of Appellant’s invention, the Examiner errs in comparing the accuracy and performance of Appellant’s humidity estimation technique with that of an actual humidity sensor. … Thus, the question is not whether it works perfectly, but whether it works at all. The Examiner offers no evidence or technical reasoning to challenge the notion that Appellant’s invention provides some amount of humidity control improvement over prior art refrigerators with no humidity control system whatsoever.

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We find persuasive Appellant’s arguments that a skilled refrigerator design engineer would be able to test a prototype refrigerator during product development by collecting data using an actual humidity sensor and correlating and comparing such data against the temperature and other parameters recited in claim 1 and develop an algorithm to estimate a humidity level. Reply Br. 3. We do not consider the prospect that such a design effort would need to be undertaken for each new refrigerator product under development constitutes “undue” experimentation. Moreover, we are not inclined to fault Appellant for not providing a precise algorithm in the Specification, when it is understood that the particulars of the algorithm may vary depending on design consideration variables such as compartment size or anticipated environmental operating conditions particular to each new product. Under the circumstances, it is enough that a person of ordinary skill in the art would have been able to derive the appropriate algorithm given a specified set of physical and operational parameters.

So, while this applicant was able to get by with a very limited example algorithm, drafters may be prudent in provide algorithm details that are to a deeper level of specificity than that claimed. In this way, the applicant is always able to point to more details in the specification in response to an assertion of lack of enablement.