## Facts

- Ariad Pharmaceuticals, along with academic institutions, owned or licensed U.S. Patent No. 6,410,516, directed to methods of regulating cell physiology by reducing activity of the transcription factor NF-κB.
- The asserted claims broadly covered methods that reduce NF-κB activity, effectively reaching the use of any substances achieving that functional result.
- The specification described NF-κB biology and proposed general categories of potential inhibitors (e.g., decoy and inhibitor molecules), but disclosed no working or prophetic examples of methods that reduce NF-κB activity and no completed syntheses of proposed molecules.
- Eli Lilly was accused of infringing via drugs (Evista and Xigris) alleged to work by inhibiting NF-κB activity.
- A jury found infringement and upheld validity; the district court denied Lilly’s JMOL motions challenging validity under 35 U.S.C. § 112, ¶ 1.
- A Federal Circuit panel reversed, holding the asserted claims invalid for lack of written description; the court granted rehearing en banc to address whether written description is distinct from enablement and, if so, whether the claims satisfied it.

## Issues

1. Whether 35 U.S.C. § 112, ¶ 1 includes a written-description requirement separate from the enablement requirement.
2. Whether the ’516 patent’s broadly functional method claims satisfy the written-description requirement.

## Decision

- The en banc Federal Circuit held that § 112, ¶ 1 contains a written-description requirement distinct from enablement.
- The court held the asserted claims invalid for failure to satisfy written description because the specification did not show that the inventors possessed the full scope of the broadly claimed methods for reducing NF-κB activity as of the filing date.
- The court affirmed the panel’s invalidity judgment, rejecting the district court’s determination that the claims were valid.

## Legal Principles

- Section 112, ¶ 1 imposes two related but distinct obligations: (1) a written description of the invention and (2) enablement (the manner and process of making and using it).
- Written description asks whether the specification reasonably conveys to a person skilled in the art that the inventor had possession of the claimed subject matter as of the filing date.
- For broad genus or functionally defined claims, describing a desired result or a research plan is insufficient; the disclosure must support the claimed scope, often through representative species or identifying features that demonstrate possession of the genus.
- Written description applies to method claims as well as composition claims; a method defined by achieving a broad functional result must be supported by disclosure of ways to achieve that result across the claim scope, not merely by stating the goal.

## Conclusion

The Federal Circuit confirmed that written description is a distinct statutory requirement and invalidated broad functional genus method claims where the specification described the biological target and proposed categories of inhibitors but failed to provide concrete disclosure showing possession of the claimed methods across their full scope.


Ariad Pharms., Inc. v. Eli Lilly & Co., 598 F.3d 1336 (Fed. Cir. 2010) (en banc)