Nothing obvious about common sense

On August 10 2016, in a rare reversal of a Patent Trial and Appeal Board (PTAB) decision in an inter partes review proceeding, the Federal Circuit in Arendi SARL v Apple Inc reversed the PTAB's decision that the subject patent claims were obvious. The court held that the PTAB had misused common sense to conclude that it would have been obvious to supply a missing limitation in a prior art reference.

Facts
Arendi was the owner of the patent in suit (US 7,917,843), which was directed to a system for beneficial coordination between a first computer system displaying a document and a second computer system for searching an external information source. Apple, Google and Motorola Mobility LLC had jointly filed a petition for inter partes review of the Arendi patent, asserting that the patent claims were obvious in view of a single prior art reference. The PTAB instituted review of a number of the claims and held that, while the prior art reference did not teach one element of the claims, it was reasonable to presume, as a matter of common sense, that it would have been obvious to the ordinary artisan to utilise the missing element.

Decision
Arendi appealed and the Federal Circuit reversed. The court started by acknowledging that common sense, common wisdom and common knowledge can be considered in analysing obviousness. However, there are at least three caveats with regard to applying "common sense":

• Common sense is typically invoked to supply a known motivation to combine, not to supply a missing claim limitation.
• In the one case where common sense was invoked to supply a missing limitation, the limitation in question was unusually simple and the technology particularly straightforward (ie, the missing limitation was simply the instruction to repeat the previous steps until a desired quantity was reached).
• Common sense cannot be used as a wholesale substitute for reasoned analysis and evidentiary support.

In the case at hand, the court agreed that the single prior art reference was missing a particular limitation with regard to performing a specific type of search, and found that the missing limitation was central to the subject claims. The court then held that the appellees had failed to show why it would be "common sense" to extrapolate from a general background knowledge of searches in a database to add a search for a telephone number to the prior art reference. In particular, the appellees did not explain with concrete examples what benefit searching for entries with the same telephone number would achieve.

The court noted that the use of common sense does not require a specific hint or suggestion in a particular prior art reference, just a reasoned explanation that avoids conclusory generalisations. Because the PTAB relied on conclusory statement and unspecific expert testimony regarding searches in general, the finding of unpatentability had to be reversed.

Comment
The decision reaffirms that mere conclusory assertions of common sense or common knowledge are not sufficient to invalidate or reject a patent claim. Any such arguments must be supported by reasoned explanations or analysis, preferably with evidentiary support.