On August 21, 2009, the Federal Circuit announced it would reconsider its decision in Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co., 560 F.3d 1366 (Fed. Cir. 2009) and address en banc the longstanding question of whether the patent law requires that a patent include a written description demonstrating that the inventor possessed the claimed invention at the time the patent application was filed. Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co., No. 2008-1248, 2009 WL 2573004 (Fed. Cir., August 21, 2009). Although important to all intellectual property–rich industries, the outcome in Ariad will be of particular significance to the biotechnology sector, as the written description requirement presents a high hurdle to obtaining patents in that space and is a common defense to patent infringement claims.

Section 112(1) of the federal patent statute, 35 U.S.C. 101, et. seq. requires that a patent "shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same."

Beginning with its decision in Regents of the University of California v. Eli Lilly, 119 F.3d 1559 (Fed. Cir. 1997), the Federal Circuit has interpreted this language as requiring patentees to include two separate elements in their patents: a written description, and an enabling disclosure. Under existing Federal Circuit precedent, the written description requirement mandates that a patentee disclose the knowledge on which the patent is based and demonstrate that the patentee possessed the claimed invention. The enablement requirement demands a disclosure that would enable a person of ordinary skill in the art to make and use the invention without undue experimentation.

Opposition to the Federal Circuit's reading of Section 112(1) as requiring a written description in addition to an enabling disclosure comes from many sources, including several Federal Circuit judges, as well as patent law practitioners and commentators. Those objectors interpret section 112(1) to simply require an enabling disclosure, without any extra requirement to demonstrate possession of the invention.

The dispute regarding the existence of a written description requirement boils down to whether the statutory phrase "shall contain a written description of the invention, and of the manner and process of making and using it…" is best read with particular emphasis on the conjunctive "and" after the comma, thus creating two separate requirements, or as simply requiring a written description that contains enough written information for others to make and use the claimed invention.

The Federal Circuit's choice between these two alternatives is particularly important to the biotechnology industry. Historically, the Federal Circuit has required a greater level of detail in the written description for biotechnology patents and patents in other "unpredictable arts" than in the more "predictable" sciences, such as software engineering. The Federal Circuit has evolved a sliding scale based on its perception of a field's predictability for deciding whether a disclosure is sufficient to allow a person of skill in the field to "visualize or recognize the identity of the subject matter purportedly described." Regents of Univ. of Cal., 119 F.3d at 1573. Under this rubric, while a software patent need not disclose the patented code to satisfy the written description requirement, a biotechnology patent almost certainly must provide a detailed description, such as a DNA or amino acid sequence to meet the requirement.

Thus, a decision by the Federal Circuit that there is no written description requirement separate from the enablement requirement would enhance the viability of biotechnology patents and permit biotechnology companies greater latitude in claiming and protecting their inventions. Likewise, elimination of the written description requirement would simplify patent prosecution and enforcement for intellectual property holders in all industries. Indeed, even if the Federal Circuit maintains a distinct written description requirement, its decision in Ariad should clarify the diktats of that requirement and reduce uncertainty as to how much detail must be included in patent specifications.

The court has not yet scheduled oral argument in this case.