This much is clear:  Proving lack of enablement requires more than an expert saying it would be “complex” or “difficult” to practice the claimed invention.  So said the Federal Circuit recently in Cephalon, Inc.  et al. v. Watson Pharmaceuticals, Inc. et al.

This appeal resulted from an opinion following a bench trial on the validity and infringement of patents covering an improved method of drug delivery.  These methods allowed for absorption of the drug directly into the bloodstream through the oral mucosa of the mouth, rather than being absorbed only after passing through the gastrointestinal system.  The District Court held that the patents were not infringed and were invalid for lack of enablement.  Cephalon appealed.

On appeal, the federal circuit affirmed the finding of no infringement, but reversed the holding of lack of enablement, concluding that the District Court had committed clear error.  35 U.S.C. § 112 requires that one skilled in the art, having read the specification, be able to practice the invention without “undue experimentation.”  Much like saying one must act “reasonably,” the standard is simple to state, but difficult to apply.  The key question is how much experimentation is “undue” experimentation.

The Federal Circuit gives us little guidance on this question, merely stating the eight illustrative, but not mandatory, factors set forth in In re Wands, 858 F.2d 731 (Fed. Cir. 1988).  To this list, the Court adds the following commentary, which adds little clarity:

• “What is relevant depends on the facts, and although experimentation must not be undue, a reasonable amount of routine experimentation required to practice a claimed invention does not violate the enablement requirement.”  Cephalon, slip op. at 9-10.
• “The question of undue experimentation is a matter of degree, and what is required is that the amount of experimentation not be ‘unduly extensive’” Id. at 13-14.

The Court then turned to the specific facts of this case and easily concluded that Watson failed to meet its burden.  Specifically, the Court faulted Watson for failing to show both the amount of experimentation that was necessary, and that such amount of experimentation was excessive.  In what are bound to be the most quoted lines from the opinion, the Court stated: “Dr. Mumper’s ipse dixit statements… cannot be enough to constitute clear and convincing evidence,” id. at 12; and  “unsubstantiated statements indicating that experimentation would be ‘difficult’ and ‘complex’ are not sufficient,” id. at 15-16.  Ultimately, this case turned not on the finer points of how much experimentation is “due” versus “undue,” but on a basic failure to support an expert’s opinion.

We take two lessons from this case.  First, there is no good way to be confident that any amount of experimentation is “undue.”  The Federal Circuit has held very significant experimentation, in dollars and time, to be reasonable and those decisions were quoted approvingly here.  Second, you need to arm your experts with the resources needed to convincingly show—not merely say—that practicing the invention was “complex” or “difficult.”  Neither of these lessons is new, but this case should serve as a valuable reminder.