Almost a decade has elapsed since the Supreme Court’s decision in KSR Int’l Co. v. Teleflex, Inc. altered the law of patent obviousness. In reversing the judgment of the Federal Circuit, the Court in KSR limited the “teaching, suggestion, motivation” test and loosened the standards that both courts and the USPTO use to assess validity under 35 U.S.C. § 103. In particular, the Court expressly rejected the application of any inflexible obviousness rule that excluded consideration of, among other things, common sense.

The Federal Circuit, however, recently confirmed that common sense alone cannot suffice to establish obviousness. In Arendi S.A.R.L. v. Apple, Inc., the court held that the Patent Trial and Appeal Board (the PTAB) erred when it used common sense to supply a missing limitation in the prior art to arrive at the claimed invention. Not only is this case surprising in that factual findings of the PTAB are rarely overturned on appeal, but it also marks some constraints on the broad obviousness standard articulated in KSR.

The patent-at-issue, U.S. Patent No. 7,917,843 (the ‘843 patent), is assigned to Arendi and was successfully challenged by Apple, Google, and Motorola Mobility (collectively “the Appellees”) in an inter partes review at the PTAB, during which claims were found to be obvious. The ‘843 patent allows use of a first computer program to display information in a first document and then use of a second computer program to search a second document for information related to the information displayed in the first document. For example, a person’s name in a first document can be used to search a second document or database for related fields, such as an address or phone number that corresponds to the person’s name. If a single related field is found, the field is inserted into the first document. If multiple related fields are found, the results of the search are displayed for the user, allowing the user to select the appropriate field to be inserted into the first document.

U.S. Patent No. 5,859,636 to Pandit (Pandit), which is the only prior art reference on appeal in this case, teaches embodiments that recognize classes of text and make suggestions based on the text. The most relevant embodiment of Pandit recognizes a phone number in a first document and generates a pull-down menu with executable operations using said phone number, such as “Add to address book.” Pandit does not disclose any search of the address book to determine whether the phone number already exists in the address book prior to the contact information being displayed to the user. However, the PTAB found that it would be “reasonable to presume as a matter of common sense” to search for duplicate phone numbers and information associated with the numbers. That is, the PTAB found that a person of ordinary skill in the art executing common sense would utilize a computerized search for duplicate phone numbers when entering phone numbers into an electronic address book. On appeal, the Federal Circuit found that the PTAB’s use of common sense to supply a missing limitation in the prior art—namely to search for the telephone number detected in a document when “Add to address book” is selected—was in error.

In assessing whether the PTAB misused “common sense” in its analysis, the Federal Circuit first reaffirmed the rationale of KSR, reiterating that common sense, common wisdom, and common knowledge are important in analyzing obviousness. In doing so, the Federal Circuit noted that “common sense” is invoked in an obviousness analysis (1) to provide a known motivation to combine, but not to supply a missing claim limitation, and (2) to supply a missing limitation to the prior art when the limitation and the underlying technology is straightforward. The court, however, also noted that common sense should not be used as a substitute for reasoned analysis and evidentiary support when a limitation is missing from the prior art. For example, the court noted that Pandit teaches text-dependent word recognition rather than performing a search of the related information as in the patent-at-issue. Because a claim limitation of searching for information in a document was missing from the prior art, and the search was an important limitation that is “not evidently and indisputably within the common knowledge of those in the art,” the Appellees had to show why it would be common sense for the “Add to address book” function to first search for entries having the same phone number.

The Federal Circuit found that the Appellees failed to meet their burden of proving that common sense would dictate that Pandit teaches to search for a phone number prior to adding the phone number to the address book. While searching for data in a database was supported by substantial evidence, the prior art lacked the teaching of performing a search using a phone number. Moreover, the Appellees failed to present the requisite evidence required to show why it would have been obvious to modify Pandit to search for a phone number, especially since searching for a phone number would not sufficiently serve the Appellees’ stated goal of preventing multiple address book entries in the event that a person has multiple phone numbers. Although the court expressed that the use of common sense does not need a showing of specificity, conclusory determinations and unspecific arguments were held insufficient to validate the use of “common sense” when assessing obviousness.

The Federal Circuit’s decision may well be an attempt to cabin the breadth of the obviousness standard set forth in KSR. For example, the Federal Circuit stressed that a finding of obviousness must be grounded in evidence, finding that it would be far too simple for a broad definition of common sense to subsume otherwise patentable inventions. Nevertheless, KSR will continue to dominate obviousness law and “[r]igid preventative rules that deny factfinders recourse to common sense” should be avoided when assessing obviousness. It will be important to keep a watchful eye towards the future to see how the Federal Circuit grapples with the mandates of KSR and fact-finders anxious to backfill gaping holes in the prior art. In the meantime, practitioners should consider relying on the findings in Arendi to overcome rejections in which the examiner relies on “common sense” without proper support.