Ariad v. Lilly: Written Description Showdown at the CAFC

Yesterday the CAFC granted rehearing en banc in Ariad v. Lilly. The order poses two questions: 1. Whether 35 U.S.C. § 112, paragraph 1, contains a written description requirement separate from an enablement requirement? and 2. If a separate written description requirement is set forth in the statute, what is the scope and purpose of the requirement?

The debate at the CAFC centers around whether the so called "written description requirement" of section 112, paragraph one, should be used to police the introduction of new matter into claims, or whether it presents a distinct requirement for patentability of claims; that is, separate from the enablement requirement of the same paragraph.

The panel decision in Ariad continued a trend that began in 1997 with litigation that also involved Eli Lilly, Regents of Univ. of Cal. v. Eli Lilly (opinion here). The 1997 Lilly case is often cited as the first to use written description as a separate requirement for patentability. In Ariad's case against Eli Lilly, the Court reversed a Massachusetts District Court and invalidated Ariad's claims broadly reciting methods of repressing the activity of NF-kB, an important regulator on gene transcription. Many saw the Ariad case as raising issues under scetion 101 relating to patent eligible subject matter, however, the panel deciding the case avoided the issue of patent eligibility by ruling that all of the asserted claims failed to comply with the written description requirement.

The problem with Ariad's claims appear to be breadth: they are broadly drawn to cover any method for reducing NF-kB activity in cells, including both known and unknown methods (on this point, see the arguments raised by Chris Holman's blog). This issue of "overbreadth" is a common one running through the CAFC's written description cases. With claims as broad as these, the question becomes which doctrine between written description and enblement, is more appropriately used to invalidate the claims.

The statute requires clarity in order to (1) put the public on notice as to what the patentee claims as his or her invention, and (2) a teaching of how to make and use the invention as part of the quid pro quo for granting a limited monopoly in the form of a patent.

In my view, both policy goals are adequately furthered by the enablement requirement. To date, the CAFC has failed to articulate a clear standard that applies the written description requirement in a way that clearly furthers either statutory goal. Perhaps the en banc court in Ariad will finally clear up this confused body of case law.