Eight Factors for Determining "Undue Experimentation" to Defeat Anticipation in the U.S.

In Impax Laboratories Inc. v. Aventis Pharmaceuticals Inc. (October 3, 2008), the U.S. Court of Appeals for the Federal Circuit identified eight factors for determining the level of "undue experimentation" required to defeat anticipation:

In order to anticipate a claimed invention, a prior art reference must enable one of ordinary skill in the art to make the invention without undue experimentation. Finisar Corp. v. DirecTV Group, Inc., 523 F.3d 1323, 1336 (Fed. Cir. 2008) (citing In re Omeprazole Patent Litig., 483 F.3d 1364, 1379 (Fed. Cir. 2007)). In other words, the prior art must enable the claimed invention. Minn. Mining & Mfg. Co. v. Chemque, Inc. (3M), 303 F.3d 1294, 1301 (Fed. Cir. 2002). The “undue experimentation” component of that equation examines (1) the quantity of experimentation; (2) the amount of direction or guidance present; (3) the presence or absence of working examples; (4) the nature of the invention; (5) the state of the prior art; (6) the relative skill of those in the art; (7) the predictability or unpredictability of the art; and (8) the breadth of the claims. In re Wands, 858 F.2d 731, 737 (Fed. Cir. 1988).

. . . The district court also did not find the dosage information in the disclosure to teach a proper treatment. Instead the trial court noted that “the dosage guidelines are broad and not specific to any of the hundreds of formula I compounds of the claimed invention or to any of the listed diseases.” Id. at 433. Moreover, the '940 patent ties the dosing information to “the compounds of the invention” and specifically excludes riluzole from the invention. Id. at 432-33. Finally, the trial court also noted the absence of working examples.

. . . In view of these findings, the district court found that one of ordinary skill in the pharmaceutical arts would have needed extensive experimentation to link riluzole with the treatment of ALS. Id. at 433. The district court then reached the ultimate conclusion that the ’940 patent does not enable claims 1-5 of the ’814 patent and thus, it is not anticipatory. As this court explained during the first appeal, when an accused infringer asserts that a prior art patent anticipates specific patent claims, the infringer enjoys a presumption that the anticipating disclosure also enables the claimed invention. Impax Labs., 468 F.3d at 1382. However, the patentee may overcome that presumption with persuasive evidence showing that the prior art patent does not enable the claimed invention.