In patent prosecution, one of the hurdles inventors face is an obviousness rejection from the United States Patent and Trademark Office (USPTO). The determination of whether an invention is obvious is governed by 35 U.S.C. § 103. According to this statute, an invention is unpatentable if the differences between it and the prior art are such that the invention would have been obvious to a person having ordinary skill in the art (the skilled artisan) at the time of the invention. Examiners form obviousness rejections with a systematic approach and usually by combining references and/or modifying references or the resulting combination. The systematic approach includes identifying a reason or rationale for why combining or modifying the identified prior art references would have been obvious to the skilled artisan, which rationale being based on the references themselves or general knowledge in the field,
The situation often arises where the inventors has recognized some unique problem or unexpected advantage achieved by the combination of features that is different from the rational cited by the examiner and used in rejecting that combination of features as obvious. Inventors often find this incredulous - they ask how an examiner can make such an assertion when the claimed invention provides a benefit or advantage that is not recognized in the prior art.
However, as explained in MPEP 2144.IV, while an examiner’s rationale for combining references must be grounded in the references or common knowledge within the field, it is not required to be the same motivation that led the inventor to the claimed combination. From the MPEP:
The reason or motivation to modify the reference may often suggest what the inventor has done, but for a different purpose or to solve a different problem. It is not necessary that the prior art suggest the combination to achieve the same advantage or result discovered by applicant.
For instance, if an invention combines elements from two different references to achieve a particular advantage not acknowledged in those references, the examiner might still form a rejection by asserting that it was obvious to combine the references for a different reason (that is allegedly based on their teachings alone).
A recent decision by the Patent Trial and Appeal Board (PTAB) provides valuable insights into this issue. Appeal 2023-002327, Application 15/759,234. The invention in this case relates to a sensor sheet for measuring biological information. Claim 1 is reproduced below:
1. A sensor sheet for biological information measurement, the
sensor sheet comprising:
a first adhesive sheet to be applied to a skin of a subject;
a second adhesive sheet to be stuck to a front surface side of the first sheet; and
an electric circuit comprising a plurality of electrodes and wires connected to the plurality of electrodes, the electric circuit provided in an area in the second adhesive sheet, wherein, the second adhesive sheet is thicker than the first adhesive sheet, the first adhesive sheet is higher in stretchability than the second adhesive sheet, the stretchability of a peripheral edge area of the second adhesive sheet is higher than that of a center area of the second adhesive sheet, and
the second adhesive sheet comprising slits extending to a peripheral edge of the second adhesive sheet.
Here, the examiner combined prior art showing a slit in a layered adhesive, but with the slit to facilitate tearing upon removal. In the invention, the purpose of the slit was to aid adhesion. Thus, not only was the purpose different, it was in direct contradiction. One might first consider this a teaching away - that would be a trap. Teaching away is very narrow at the USPTO and likely would have been ineffective here (see here, here, and here, for example).
Having considered the competing positions of Appellant and the Examiner in light of the teachings and expressed purpose of Schoendorfer, we are not persuaded that a person of ordinary skill in the art would have had the requisite motivation to combine the prior art in the manner proposed by the Examiner. Appellant’s invention is directed to aiding a user that desires to retain a biological sensor in place. To this end, Appellant uses slits to moderate a sharp stretchability change to prevent upper sheet 420 from coming off of lower sheet 410. Spec. ¶ 75. In contrast, Schoendorfer uses slits to facilitate tearing upon (presumably unauthorized) removal in the context of conducting drug testing. In the operational environment of Schoendorfer, the administrator of the drug test desires for the patch to remain in place while the user (wearer) of the patch may have incentive to tamper with or remove the patch in the hopes of defeating the drug test.
It seems to us that the slits of Appellant’s invention and Schoendorfer operate at cross-purposes to each other. This makes Schoendorfer an unlikely reference to combine with the Examiner’s other applied art to achieve the claimed invention. The Examiner’s stated rationale for making the combination, namely, to indicate whether the wearer has likely tampered with the patch, does not strike us as a persuasive rationale for combining the prior art to achieve the claimed invention. Although it may be true that we should look not “only to the problem the patentee was trying to solve” (KSR, 550 U.S. at 420), and that a skilled artisan need not be motivated to combine the prior art for the same reason as an inventor (Kahn, 441 F.3d at 990), we see no reason why a person of ordinary skill in the art would be motivated to make a biologic sensor tamper proof by using peripheral slits. Appellant’s biologic sensor invention includes a memory to record data or includes a wireless transmission capability to forward data. Spec. ¶ 20. We are not persuaded that a person of ordinary skill in the art, in designing a biological sensor, would have any need or motivation to put slits in the peripheral edge to prevent a wearer from tampering with the sensor. Any such tampering would likely be detected from analyzing the data that is captured by the sensor, thereby obviating any need to modify the peripheral edge with slits. The Examiner’s findings of fact as to motivation to combine, are not supported by a preponderance of the evidence. The Examiner’s legal conclusion of unpatentability is not well-founded.
In this context, the PTAB’s analysis considered not only whether the prior art references has some basis to support a rationale for the combination, but also that this supposed rationale was at cross-purposes with the inventor’s reasoning.
Thus, in practice, while the general rule noted above still applies, the PTAB may be more receptive to the idea that the examiner’s rationale is not properly supported when the facts of a case suggest that prior art references are at cross-purposes with the inventor’s motivation. Highlighting that the prior art’s goals are misaligned with the claimed invention’s benefits can make the examiner’s rationale for combining references seem less persuasive. This approach may increase the likelihood that the PTAB will view the examiner’s reasoning with skepticism, potentially leading to a more favorable outcome for the inventor.