In two recent decisions, the U.S. Court of Appeals for the Federal Circuit articulated the ways in which other patent validity doctrines are implicated when asserting that a reference is anticipating. The first case held that a reference was not anticipating because it was not enabled. In the second case, the Federal Circuit emphasized that a prior art reference could be anticipated yet nonobvious when it reversed and remanded a district court’s grant of judgment as a matter of law on the issue of anticipation. These cases shed light on the factors a party should consider when asserting invalidity based on anticipation by prior art. See Impax Labs., Inc. v. Aventis Pharms. Inc., No. 2007-1513, 2008 WL 4447096 (Fed. Cir. Oct. 3, 2008); Cohesive Techs., Inc., v. Waters Corp., Nos. 2008-1029, 2208-1030, 2008-1031, 2008-1032, 2008-1059, 2008 WL 4472884 (Fed. Cir. Oct. 7, 2008).

Anticipatory Reference Must Be Enabled Without Requiring Undue Experimentation

In Impax, the patent-in-suit, U.S. Patent No. 5,527,814 (“the ‘814 patent”), related to a method of treatment concerning the use of riluzole to treat amyotrophic lateral sclerosis (ALS). 2008 WL 4447096, *1. Impax, holder of an Abbreviated New Drug Application for generic riluzole, appealed the district court’s decision that the claims of the patent-in-suit were not anticipated by the asserted prior art patent, U.S. Patent No. 5,236,940 (“the ‘940 patent”). Id.

The district court initially found that the ‘814 patent was not anticipated because the ‘940 patent “did not put one of ordinary skill in the possession of the invention.” Id. at *2. On appeal, the Federal Circuit remanded for a specific determination of whether the ‘940 patent would “enable a person of ordinary skill in the art to treat ALS with riluzole without regard to the efficacy of such treatment.” Id.

On remand, the district court made additional findings of fact and determined that “excessive experimentation would have been necessary to practice the invention.” Id. To support this opinion, the trial court found that the ‘940 patent disclosed “hundreds of thousands of compounds and several diseases,” and “nothing in the ‘940 patent would direct one skilled in the art to recognize that riluzole could be used to treat ALS.” Id. Although the ‘940 patent referred to riluzole, the district court rejected the notion that the “mere mention” of riluzole was sufficient to show enablement. Id.

The Federal Circuit agreed. The Court determined that there was sufficient evidence to overcome the presumption of enablement because the alleged anticipatory reference (1) contained broad and general dosage guidelines without sufficient guidance to prescribe a treatment regimen, (2) contained no working examples, and (3) would not lead one of skill in the art to identify riluzole as a treatment for ALS. Id. at *3. “In sum, each component of the claimed invention … would require undue experimentation based on the teachings of the ‘940 patent.” Id. Thus, the Court appeared to require the alleged anticipatory prior art to enable practicing the claimed method.

A Claim Can Be Anticipated, Yet Not Obvious

In Cohesive, the defendant alleged inter alia that claims of the plaintiff’s patent were anticipated and obvious in light of seven separate prior art references. 2008 WL 4472884, *3. Near the end of the jury trial, the district court judge held a charge conference and sua sponte entered a directed verdict of no anticipation. Id. The judge based this decision on his determination that the anticipation case was “iffy” and the defendant’s contentions were “best captured by obviousness.” Id. at *7 (citations omitted).

The Federal Circuit determined that the district court “was wrong to conclude that granting judgment as a matter of law on anticipation would not harm [the defendant] simply because the jury had the opportunity to consider the same references for obviousness.” Id. at *7-8. The Court turned on its head the “often quoted legal maxim that anticipation is the ‘epitome of obviousness,’” noting that a verdict of nonobviousness would not necessarily foreclose a finding of anticipation. Id. at *8.

In so doing, the Federal Circuit emphasized that there are separate tests for determining obviousness and anticipation. Id. Three primary differences between the tests are that (1) obviousness can be proven by combining existing prior art references, while anticipation requires all elements of a claim to be disclosed within a single reference, (2) obviousness requires analysis of secondary considerations of nonobviousness, while secondary considerations are not an element of anticipation, and (3) although anticipation can be proven inherently, proof of inherent anticipation is not the same as proof of obviousness. Id. The Court provided the following example to support its decision:

Consider, for example, a claim directed toward a particular alloy of metal. The claimed metal alloy may have all the hallmarks of a nonobvious invention—there was a long felt but unresolved need for an alloy with the properties of the claimed alloy, others may have tried and failed to produce such an alloy, and, once disclosed, the claimed alloy may have received high praise and seen commercial success. Nevertheless, there may be a centuries-old alchemy textbook that, while not describing any metal alloys, describes a method that, if practiced precisely, actually produced the claimed alloy. While the prior art alchemy textbook inherently anticipates the claim under § 102, the claim may not be said to be obvious under § 103.

Id. at *8, n. 2. The Court noted that this example represented “precisely why our precedent has rejected reliance on the ‘legal homily’ that ‘anticipation is the epitome of obviousness.’” Id. (citation omitted).

Judge Rader dissented, finding the majority’s decision to remand the directed verdict “a waste of time and resources” in this case, since the jury returned a verdict of nonobviousness. Id. at *19. Conceding that a claim could be obvious but not anticipated, he argued that it’s not possible that a claim could be anticipated but nonobvious. Id. at *20. Such a claim by the majority, he argued, “flies in the face of a long line of precedent to the contrary.” Id.