By:Audrey Millemann

The Federal Circuit Court of Appeals has reaffirmed that patent applications must satisfy a written description requirement separate from the enablement requirement. In Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co., 598 F.3d 1336 (Fed. Cir. 2010), an en banc Court of Appeals held that 35 U.S.C. §112, first paragraph, contains a written description requirement separate and in addition to the enablement requirement. 

The plaintiff, Ariad Pharmaceuticals, sued Eli Lilly for infringement of a patent pertaining to methods for using a transcription factor to modify gene expression. At trial, the jury found that Eli Lilly had infringed the patent and that the claims of the patent were valid. The district court denied Eli Lilly’s motion for judgment as a matter of law. 

Eli Lilly appealed. A panel of the Federal Circuit reversed the jury verdict and found that the patent was invalid for lack of a written description under 35 U.S.C. §112, first paragraph. Ariad petitioned the court of appeals for a rehearing en banc

The Court of Appeals identified two issues to be decided.  The first issue was whether 35 U.S.C. §112, first paragraph, includes a written description requirement separate from the enablement requirement. If there is such a requirement, the second issue was the scope and purpose of the requirement.

Ariad argued that there is no written description requirement in §112, first paragraph, separate from the enablement requirement. Ariad contended that §112 has two description requirements: first, what the invention is, and second, how to make and use the invention, but that the first requirement only applied in connection with issues of priority (e.g., amended claims, foreign and provisional priority, and interferences) because original claims themselves satisfy the written description requirement. Eli Lilly agreed with Ariad on the two different description requirements, but asserted that both requirements apply to all claims, including original claims.

The Court of Appeals first analyzed the statute’s language. The court agreed with Eli Lilly that the statute requires the specification to contain a “written description of the invention and of the manner and process of making and using it.” The court noted that Congress could have written §112 to refer only to an enablement requirement, but did not do so. 

The court next discussed Supreme Court precedent. The court stated at 1345:

“Like Lilly, we also read Supreme Court precedent as recognizing a written description requirement separate from an enablement requirement even after the introduction of claims…The Court ascribed two purposes to this portion of the statute, only the first of which involved enablement: ‘(1) to require the patentee to describe his invention so that others may construct and use it after the expiration of the patent and (2) to inform the public during the life of the patent of the limits of the monopoly asserted, so that it may be known which features may be safely used or manufactured without a license and which may not.’[Citation omitted.]”

The court explained the different purposes of the claims and the written description requirement, at 1347: 

“Claims define the subject matter that, after examination, has been found to meet the statutory requirements for a patent. [Citation omitted.] Their principal function, therefore, is to provide notice of the boundaries of the right to exclude and to define limits; it is not to describe the invention, although their original language contributes to the description and in certain cases satisfies it. Claims defined and circumscribe, the written description discloses and teaches.”