The Ohio Willow Wood Company (OWW) sued Alps South, LLC (Alps) for infringement of U.S. Patent No. 5,830,237 (‘237 patent). The patent relates to cushioning devices that go over the residual stumps of amputated limbs to make the use of prosthetics more comfortable. The U.S. District Court for the Southern District of Ohio stayed the litigation from November 2006 until November 2011, pending the completion of several reexamination proceedings. After the stay lifted, the parties moved for summary judgment. The District Court granted summary judgment that: (1) OWW was collaterally estopped form challenging the invalidity of claims 1, 2, 4, 15, 16, and 20; (2) claims 18, 19, 21, 22, and 23 were invalid for obviousness; and (3) Alps failed to raise a genuine issue of material fact with respect to inequitable conduct. The Federal Circuit affirmed on the issues of collateral estoppel and obviousness, but reversed and remanded on the issue of inequitable conduct.

The Federal Circuit reviewed the collateral estoppel finding de novo. On appeal, OWW argued that the mere existence of different language in the adjudicated claims of the ‘182 patent (the parent patent that was previously adjudicated as invalid) and the un-adjudicated claims of the ‘237 patent alone were sufficient to overcome collateral estoppel. The Federal Circuit held that the proper inquiry was whether there was an identity of the issues litigated. Here, the asserted claims had slightly different claim language, but in affirming the district court, the Federal Circuit found that OWW failed to explain how the mere use of different words altered the invalidity determination.

Then, the Federal Circuit reviewed the summary judgment decision regarding obviousness de novo. The claims at-issue were dependent claims placing limits on items in independent claim 1. OWW sought reversal by arguing that the District Court did not perform an adequate obviousness analysis to support summary judgment. In affirming the invalidity of dependent claims 18, 19, 21, 22, and 23 for obviousness, the Federal Circuit rejected OWW’s arguments and evidence, finding no genuine issue of material fact that one of ordinary skill in the art would have combined the references in a manner that render the claims obvious.

Finally, the Federal Circuit evaluated inequitable conduct. Proof of inequitable conduct requires that a challenger show, by clear and convincing evidence, that the patent applicant: (1) misrepresented or omitted information material to patentability; and; (2) did so with specific intent to mislead or deceive the PTO. In a prior reexamination of the ‘237 patent, OWW alleged that there was no corroboration of the declaration that was filed by Alps to allege that the claims were unpatentble. The court applied a “rule of reason” standard to evaluate materiality. In finding that OWW could have provided various documents and samples that were contrary to OWW’s corroboration argument, the Federal Circuit held that: (1) a reasonable finder of fact could conclude that OWW withheld evidence from the PTO during the second reexamination; (2) the evidence could be sufficient to demonstrate the materiality prong; (3) and there was a genuine issue of fact as to whether conduct was undertaken with deceptive intent. The Federal Circuit thus reversed the grant of summary judgment on the issue of inequitable conduct and remanded that issue for trial.

A copy of the opinion can be found here.