The law of obviousness has many facets. One that arises frequently when using claimed ranges is optimization. Several previous posts have discussed optimization of ranges in the past (e.g., here). As explained in the MPEP, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. Sometimes a rejection under this theory can be addressed by pointing out that the prior art has not recognized the particular parameter as a result-effective variable. However, that is not the only line of attack that is possible.

Another approach for addressing a rejection relying on an optimization of ranges is illustrated in a recent appeal decision - Appeal 2022-002449, Application 14/524,818.

The application relates to methods and devices for the treatment of obstructive sleep apnea syndrome by retraction of soft tissue in the oral cavity and pharynx, and to devices implanted within the tongue that are used for diagnosis and treatment of medical disorders.

Claim 1, is reproduced below:

1. An implantable tissue retractor for treatment of a breathing disorder, the implantable tissue retractor comprising:
a linear shaft adapted to be disposed in a soft tissue located in a patient’s oral cavity or pharynx;
a retractor member connected at or near a first end of the shaft; and
an anchor member connected at or near a second end of the shaft, wherein the implantable tissue retractor is configured to be totally implanted within the soft tissue and engage only the soft tissue,
wherein the implantable tissue retractor is adapted to exert a counterforce on the soft tissue sufficient to prevent a deformation of at least a portion of the soft tissue while allowing the shaft to stretch when subjected to a predetermined force exerted on the implantable tissue retractor by the soft tissue, and the counterforce is between 0.1 grams per cm2 and 100 grams per cm2.

At issue was the last limitation of the claim related to the predetermined force. The examiner asserted that it would have been obvious to one having ordinary skill in the art at the time of invention to provide the counterforce being between 0.1 grams per cm 2 and 100 grams per cm2, since it has been held that where the general working conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art.

Specifically, the examiner reasoned that one having ordinary skill in the art at the time of the invention would have found it obvious that the counterforce would vary depending on the anatomy of each individual, and so finding the particular force was merely routine optimization. The examiner relied on prior art that focused on treatment of Gastroesophageal reflux disease (GERD).

The PTAB disagreed with the Examiner’s reasoning:

… the Examiner does not establish that the general working conditions of the claimed tissue retractor, which is used for treatment of a breathing disorder, are disclosed by DeVries’s tissue fastener, which is used for treatment of GERD. DeVries teaches folding fundus wall 6 of the stomach back onto the esophageal wall 4, and securing the multiple tissue layers between fastening members 511 and 513 of tissue fastener 501 using a compressive force. The fastener “should be strong enough to hold the esophagus and fundus together with a force of approximately 6 lbs” and also “strong enough to maintain its integrity and utility even under stressful events, such as running, swimming, sneezing, coughing, vomiting, or the like.”

In contrast, the claimed tissue retractor includes a linear shaft adapted to be disposed in a soft tissue located in a patient’s oral cavity or pharynx. The claimed implantable tissue retractor does not firmly hold together two different tissue masses. Instead, it is totally implanted within soft tissue and adapted to exert a very small amount of counterforce on the soft tissue to prevent a deformation in soft tissue in a patient’s oral cavity, i.e., between 0.1 grams per cm2 and 100 grams per cm 2 of counterforce. .. Given the different working conditions for DeVries’s tissue fastener and the claimed tissue retractor, we are not persuaded that modifying DeVries’s tissue fastener to arrive at the claimed tissue retractor is a matter of routine optimization. Additionally, the Examiner does not identify what parameter in DeVries would be optimized by a person of ordinary skill in the art to arrive at the claimed counterforce, much less adequately explain how arriving at the claimed range of counterforce values would have been a matter of routine experimentation for a person of ordinary skill in the art.

Of note here is that the applicant used an expert declaration to establish that the prior art’s tissue fastener exerts about 30 times more force that the claimed range.

Remember that when an examiner relies on routine optimization, the examiner must still provide some rational underpinning explaining why a person of ordinary skill in the art would have arrived at the claimed invention through routine optimization why they would have had a reasonable expectation of success in doing so.