Written Description Must Do More Than Make Claimed Subject Matter Obvious

In Knowles Electronics, LLC v. Cirrus Logic, Inc., [2016-2010] (March 1, 2018), the Federal Circuit affirmed the PTAB affirmance of the Examiner that claims 1−4 of U.S. Patent No. 6,781,231 were anticipated, and that new claims 23−27 for lack of an adequate written description.

Knowles argued that the term “package” should be construed to
mean an assembly that “requires a second-level connection
with a mounting mechanism.”  However, as the Federal Circuit noted, neither the claims nor the specification specify the type of connection required.  Because intrinsic evidence is not definitive, the Federal Circuit turned to extrinsic evidence, and found support in the definitions that the PTAB selected.  Although Knowles complained that the Board impermissibly selected the broadest definition, but the Federal Circuit rejected this, finding the Board reviewed all extrinsic evidence, including evidence proffered by Knowles.

Regarding the support for the new claims, the Federal Circuit said that the written description must clearly allow a PHOSITA to recognize that the inventor invented what is claimed.  A description which renders obvious a
claimed invention is not sufficient to satisfy the written description requirement of that invention.  The amended claims require solder pads “configured to mechanically attach and electrically connect the package to a surface of an external printed circuit board using a solder reflow process,” however the specification merely discloses a genus―solder pads that are capable of being connected to a board, and fails completely to disclose the newly claimed species of such pads―pads that are connectable to a board specifically by using a reflow process.

The Federal Circuit rejected the Knowles argument that the PTAB disregarded “the state of the art at the time of filing” and “prior art knowledge” that would have demonstrated that a PHOSITA knew
solder pads were “intended to be capable of reflow attachment
to a user’s board.”  Given uncertainties in the art, and at best a passing
reference to solder pads in the specification, the PTAB reasonably found that a PHOSITA would not have recognized that the inventor possessed solder pads “configured to” connect to a printed circuit board through a reflow process.  The Federal Circuit further noted that the consideration
for adequate written description asks what the applicant conveyed with reasonable clarity, and the ’231 patent “failed to even mention, much less spell out any detail of, the claimed reflow process”).

Judge Newman dissented because the claim construction adopted by the PTAB, and affirmed by the Federal Circuit was at odds with the construction of the same claims in a prior Federal Circuit case, which she believed should be binding.