Recently, the Federal Circuit in Knorr-Bremse v. Dana overruled almost twenty years of precedent by striking down the adverse inference doctrine, which had created a negative presumption against any alleged patent infringer for failing to obtain and disclose a patent opinion letter at trial. The decision, while strongly supported by numerous intellectual property and business associations, has created uncertainty for patent attorneys regarding the use of opinion letters in litigation and the acceptable methods for proving willful infringement. This iBrief addresses two specific questions left unanswered by the decision. It concludes that (1) Federal Circuit precedent strongly suggests that the plaintiff may inform the fact-finder that the alleged infringer failed to consult legal counsel, and (2) willful infringement findings can probably be avoided even absent an opinion from counsel, as long as the alleged infringer makes a showing of good faith intent to avoid infringement.
Joshua Stowell, Willful Infringement and the Evidentiary Value of Opinion Letters After Knorr–Bremse v. Dana, 4 Duke Law & Technology Review 1-17 (2005)