In Ariad Pharmaceutical v. Eli Lilly, 2008-1248, the en banc Court of Appeals for the Federal Circuit (CAFC) in a 9-2 decision reaffirmed the existence of an independent written description requirement, separate from enablement, in 35 U.S.C. § 112, ¶1 (first paragraph).

Ariad Pharmaceuticals and its research partners (collectively, “Ariad”) brought suit against Eli Lilly (“Lilly”) alleging infringement of U.S. Patent No. 6,410,516 (“the ’516 patent”), covering methods to regulate the activity of protein called NF-kB that regulates gene activity. After a jury’s finding of infringement at trial, the case was appealed to a panel of the CAFC which found the claims at issue invalid for lack of written description in Ariad Pharms., Inc. v. Eli Lilly & Co., 560 F.3d 1366 (Fed. Cir. 2009). Ariad petitioned for a rehearing by the CAFC en banc, which was granted to address the lingering controversy regarding the existence of an independent written description requirement in § 112, ¶1.

The claims at issue are broad genus claims for any method for reducing the binding of the protein NF-kB to the binding sites on genes that it regulates. The specification hypothesizes three types of molecules that may interfere with NF-kB binding: decoys, interfering molecules, and inhibitors.

Both parties conceded, and many of the amicus briefs received by the CAFC agreed, that a written description of the invention is required by § 112, ¶1. However Ariad argued that the written description requirement was not independent of the enablement requirement, and that the legal sufficiency of a written description is judged only by whether it enables one skilled in the art.

Based on a close reading of the statutory language the CAFC concluded that “§ 112, first paragraph, contains two separate description requirements: a written description [i] of the invention, and [ii] of the manner and process of making and using [the invention].” In addition the CAFC studied the grammatical structure of the text and concluded “[t]he prepositional phrase ‘in such full, clear, concise, and exact terms as to enable any person skilled in the art . . . to make and use the same’ modifies only ‘the written description . . . of the manner and process of making and using [the invention].’” Thus the CAFC found that while the statute required the written description of the use of the invention (“and of the manner and process of making and using it”) was subject to the subsequent enablement standard, the written description of the invention itself (“The specification shall contain a written description of the invention”) was not. The CAFC concluded “That the adequacy of the description of the manner and process of making and using the invention is judged by whether that description enables one skilled in the art to make and use the same follows from the parallelism of the language.” The CAFC found an alternate interpretation would make the enabling description of use (“and of the manner and process of making and using it”) redundant, violating the rule of statutory construction that Congress does not use unnecessary words.

Additionally, the CAFC noted the written description requirement is a longstanding and independent part of the quid pro quo of a patent. A full written description also allows “the United States Patent and Trademark Office (“PTO”) to examine applications effectively; courts to understand the invention, determine compliance with the statute, and to construe the claims; and the public to understand and improve upon the invention and to avoid the claimed boundaries of the patentee’s exclusive rights.”

The CAFC canvassed several precedents supported its interpretation of a separate written description requirement including O’Reilly v. Morse, 56 U.S. 62 (1853); Schriber-Schroth Co. v. Cleveland Trust Co., 305 U.S. 47 (1938); and Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722, 736 (2002). In particular Festo confirmed the written description requirement exists as a separate element of every patent (“[T]he patent application must describe, enable, and set forth the best mode of carrying out the invention”). The CAFC also felt compelled by stare decisis to continue the accepted interpretation of the statute, concluding “to change course now would disrupt the settled expectations of the inventing community.”

The CAFC then turned to Ariad’s argument that the requirement to describe what the invention is does not apply to original claims because original claims, as part of the original disclosure, constitute their own written description of the invention. However the CAFC noted that functional language used to define a broad genus claim may merely claim a desired result, without describing individual species members that achieve that result. The CAFC further noted it was accepted that ” an adequate written description of a claimed genus requires more than a generic statement of an invention’s boundaries.” Instead a sufficient description of such a function genus would require “the disclosure of either a representative number of species falling within the scope of the genus or structural features common to the members of the genus.” The CAFC pointedly noted that the facts of this case illustrated this problem, with claims describing “methods encompassing a genus of materials achieving a stated useful result, i.e., reducing NF-kB binding” without disclosing specific species that achieve this result.

The en banc CAFC adopted the original panel’s application of the written description doctrine to the facts of the case and adopted that reasoning, finding Ariad’s asserted claims invalid, as the en banc Court’s decision.