The issues around obviousness can be subtle. Today we discuss the apparent contradiction that occurs when an examiner cites a reference “solely” for a specific teaching, and thus appears to ignore the requirement to consider the references as a whole.

MPEP 2141.02 VI discusses how the prior art “must be considered in its entirety”, including disclosures that teach away. This is not to be confused with the requirement to consider the claimed invention as a whole. However, examiners often cite to a disclosure in a reference “solely” for a specific teaching. This is usually because there are teachings in other parts of the reference that are unhelpful to the rejection. So how does one reconcile this apparent contradiction? Is the examiner allowed to do this?

One way to frame this situation is to consider whether the examiner is citing a reference more for an evidentiary purpose, rather than for what the reference teaches as a whole.

Consider a recent appeal by Sharp. Appeal 2021-003779, Application 16/732,381. The invention relates to an information recording medium in which information can be recorded and a playback device capable of playing back the information recording medium. In particular, the same modulation method is used for two different types of stored information, the method being a particular protocol - a 1-7PP (Parity Preserve/Prohibit RMTR (Repeated Minimum Translation Run Length)) modulation recording method. Claim 1 is set forth below:

1. A method for playing back an information recording medium, said information recording medium comprising:
a first region in which type identification information for identifying a type of the information recording medium is recorded by recesses and/or protrusions which are formed by a given modulation method and whose lengths are longer than a length of an optical system resolution limit of a playback device; and
a second region in which content data is recorded by recesses and/or protrusions which are formed by the given modulation method and which include a recess and/or a protrusion whose length is shorter than the length of the optical system resolution limit, the first region containing first address information recorded therein in a first address data format, the second region containing second address information recorded therein in a second address data format that differs from the first address data format, and
the given modulation method being a 1-7PP (Parity Preserve/Prohibit RMTR (Repeated Minimum Translation Run Length)) modulation recording method,
said method comprising determining playback setting of the second region based on type identification information obtained by irradiating the first region with playback light.

The examiner relied on several references. A first pair or references were combined, one of which showed the same method for two different data types, but using a different method. A third reference (Ohbi) taught different methods for different data types, one of which was the 1-7PP modulation method. The examiner relied on the third reference “solely for its teaching of 1-7PP modulation recording” methods. The examiner asserted that the 1-7PP method “would have been applicable in any area of digital recording, because it involves processing bits, which is present in any one of magnetic, optical systems, or magneto-optical systems.”

The Applicant objected asserting that one must consider the third reference (Ohbi) for all that it teaches, including that it pointed out disadvantages of the 1-7PP method.

However, the PTAB was unconvinced. First, the PTAB seems to have found that the examiner was citing Ohbi not for all that it teaches, but just for the proposition that the 1-7PP method was a well known option:

The Examiner further finds, “[t]he missing feature, a 1-7PP modulation recording method, is a very well-known concept, and is taught by several references found during the Examiner's search.” Further, the Examiner relied on Ohbi in paragraph 118 as teaching “1-7PP as one of many well-known modulation recording schemes,” and “[p]aragraph 0120 of Ohbi [ ] teaches that adopting 1-7PP modulation provides increased recording density and boost data efficiency.”

In other words, the examiner was not necessarily combining parts of Ohbi’s system with the other prior art and instead was using Ohbi as evidence for the assertion that a 1-7PP method is well known and provides increased recording density.

Second, although the PTAB did consider arguments as to other teachings in Ohbi, the PTAB brushed aside the teaching away issue using its well-trodden approach of noting that a teaching of a mere disadvantage or preference is not a teaching away.

So, be careful responding to rejections where an examiner cites a reference “solely” for one aspect of its disclosure. While this is likely a red flag that there are other aspects of the reference unhelpful to the rejection, one must understand how the citation is actually being used in the rejection. If the applicant does not fully appreciate the examiner’s approach, arguments attacking the rejection may be ineffective.