Impeaching Finnigan and Realigning the Corroboration Standard for Uninterested Single Witness Testimony with Precedent and Policy

Thomson3 3 and Finnigan4 were decided by different panels of Federal Circuit judges with one judge in common,5 only four and a half months apart. Both panels addressed whether an uninterested witness’s testimony must be corroborated, and both panels reached different outcomes. Although the latter of the two cases, Finnigan, attempted to reconcile the apparent inconsistencies, its craftsmanship suggests a veiled attempt to overrule Thomson,6 rather than distinguish it.7 Even though most courts have followed Finnigan8 instead of Thomson,9 Thomson deserves special attention--not only because it has not been overruled,10 but also because its holding is a natural extension of legal precedent and patent policy that may prove to be the more contoured rule to the issue at hand. Namely, whether an uninterested witness’s testimony submitted to prove patent invalidity must be corroborated with other evidence as a bright-line rule or whether courts should have the option to evaluate this testimony on a case-by-case basis. In other words, the issue discussed in the conflicting holdings of Thomson and Finnigan is whether a single witness’s testimony is ever sufficient to meet the evidentiary burden of clear and convincing evidence to prove patent invalidity.