"It is for ordinary minds, and not for psychoanalysts, that our rules of evidence are framed. They have their source very often in considerations of administrative convenience, of practical expediency, and not in rules of logic. When the risk of confusion is so great as to upset the balance of advantage, the evidence goes out." Minemyer v. B-Roc Representatives, Inc., Case No. 07 C 1763 (N.D. Ill. Feb. 2, 2012 Order) at 10-11. With this in mind, the Minemyer Court denied defendants' attempt to introduce to the jury, in defense of plaintiff's claim of willful infringement, evidence of the prosecution history of plaintiff's patent.
In Minemyer, Minemyer sued B-Roc for patent infringement including willful infringement. In defense of the claim of willful infringement B-Roc attempted to argue that the prosecution history of Minemyer's patent weighed against a finding of willful infringement. Specifically, B-Roc intended to argue that the various office actions in plaintiff's patent, "were relevant because they supposedly tended to show an absence of objective recklessness." Order at 6. The Court concluded that evidence of the various office actions were not only irrelevant under Rule 401 and thus inadmissible under Rule 402, but were also properly excluded under Rule 403 because such evidence had the potential to confuse the jury.
Minemyer Order.pdf