At least in ex parte appellate practice before the PTAB, the patent professional must be extremely careful in how arguments are presented to ensure that nothing is taken out of context. While this seems simple in theory, it becomes challenging in practice. Sometimes, when trying to get a point across, additional statements are made that give the PTAB an easy way to discard the overall argument. We call this the PTAB side-step, not to be confused with other more well-known dances at the PTAB.

One example of the PTAB side-step is with regard to teaching away. We’ve covered teaching away in various previous posts and noted that the USPTO takes a very narrow view of what qualifies as teaching away. Consider that a patent professional might make a passing reference as to how a reference goes “in a different direction” or the like. Some PTAB judges can latch on to this language and re-characterize the entire argument as a “teaching away” argument, even thought the argument was perhaps more nuanced. From there, the PTAB can often then more easily dismiss the entire argument because teaching away requires a very specific set of facts that rarely occur.

Today we see an example where arguments about the prior art showing extra features is highlighted by the PTAB as a way to affirm the rejection. The case is Appeal 2022-001426, Application 15/833,564, related to a diagnostic system (leak detection) for a closed fluid system (such as in an aircraft) that includes two fluid subsystems connected via a valve or actuator.

Remember - whenever an appellant argues (or whenever the PTAB can re-characterize an appellant’s argument as one in which) the prior art fails to show the claimed invention because it shows extra features, the Board will typically then inquire whether the claim excludes the additional feature.

Claim 1 is reproduced below:

1. A diagnostic system for a closed fluid system composed of a first fluid subsystem and a second fluid subsystem
connected using a valve, the diagnostic system comprising:
a first sensor disposed in the first fluid subsystem and configured to measure a first fluid level of the first fluid subsystem, and output first time-ordered fluid level measurements corresponding thereto;
a second sensor disposed in the second fluid subsystem and configured to measure a second fluid level of the second fluid subsystem, and output second time-ordered fluid level measurements corresponding thereto; and
a computer coupled to the first sensor and the second sensor, and configured to:
receive the first time-ordered fluid level measurements and the second time-ordered fluid level measurements from respectively the first sensor and the second sensor;
perform a comparison of the first fluid level with the second fluid level from the first time-ordered fluid level measurements and the second time-ordered fluid level measurements;
produce a notification indicating a predicted malfunction of the valve when, based on the comparison, the first time-ordered fluid level measurements and the second time-ordered fluid level measurements have at least a threshold divergence; and
output the notification for display to a user.

The examiner rejected the application as obvious in view of a single reference. The applicant argued that the examiner did not clearly map the claim limitations to the prior art, in part because the prior art used multiple comparisons and it was not clear which comparison was being relied upon to reject the claim (as the claim requires “ a comparison of the first fluid level with the second fluid level from the first time-ordered fluid level measurements and the second time-ordered fluid level measurements” and then a notification based thereon.

The applicant argued on appeal that the prior art (Kim) considered two conditions and thus required more than what is claimed in that “Kim teaches three comparisons wherein a third comparison is dependent upon the results of the first two comparisons.” The application went on to explain that none of the comparisons in Kim compare the first fluid level with the second fluid level from the first and second time-ordered measurements, respectively. The PTAB responded as follows:

Appellant’s arguments are unpersuasive of reversible error because Appellant does not sufficiently explain how claim 1 excludes Kim’s comparisons. See In re Van Geuns, 988 F.2d 1181, 1184 (Fed. Cir. 1993) (rejecting appellant’s nonobviousness argument as based on limitation not recited in claim); In re Self, 671 F.2d 1344, 1348 (CCPA 1982) (“Many of appellant’s arguments fail from the outset because, as the solicitor has pointed out, they are not based on limitations appearing in the claims.”). Claim 1 uses “comprising” language and, as stated by the Examiner at page 7 of the Answer, recites limitations that do not exclude the additional comparisons that Kim teaches. Appellant fails to explain how the broadest reasonable interpretation of claim 1, in light of the Specification, would exclude Kim’s comparisons

Thus, while the Applicant did point out that the prior art included additional features, it was arguably in the context of explaining how neither of the comparisons in the prior art met the claim limitation. Instead, the PTAB effectively dismisses the argument by shifting the issue back to the applicant. Whether or not the prior art did disclose the claim issue under the appropriate BRI is thus never really answered.

In the end, the Applicant here was able to make further amendments with an RCE and secure an allowance.

So, be careful not to use language in your appeal brief that enables the PTAB to take some liberties with your argument and reposition things for an easy affirmance.