On March 22, 2010, in a 9-2 en banc decision, the US Court of Appeals for the Federal Circuit confirmed that the Patent Act contains a written description requirement separate from the enablement requirement. In doing so, the court clarified a line of decisions recognizing this distinction, explained its previously stated “possession” standard, and held that the written description requirement is not restricted to establishing priority and applies to all claims.

The case, Ariad Pharmaceuticals, Inc. et al. v. Eli Lilly & Co., No. 2008-1248, concerned US Patent No. 6,410,516, which describes the regulation of gene expression by the transcription factor NF-?B. The claims at issue were directed to general methods for reducing NF-?B activity. Although the patent specification did not describe specific methods for interfering with NF-?B activity, it did mention three classes of molecules that were potentially capable of doing so. At issue was whether the specification satisfied the written description requirement for the method claims that encompassed a genus of interfering molecules, despite lacking a description of the particular species of molecules that could be used to implement the method.

In the district court proceedings, a jury found the patent was infringed and not invalid. Following the denial of its subsequent motion for judgment as a matter of law, Lilly appealed. A panel of the Federal Circuit reversed the district court’s decision, holding the asserted claims were invalid for failure to meet the written description requirement. Ariad submitted a petition for rehearing en banc, which the court granted. The court asked the parties to address (i) whether § 112, first paragraph, contains a written description separate from the enablement requirement and (ii) if so, the scope and purpose of that requirement.

Ariad answered the first question in the negative, arguing that the written description requirement was subsumed by the enablement requirement, and that the written description requirement was only implicated in the context of determining the priority of amended claims. Parsing the language of the statute, the majority rejected Ariad’s position as a matter of statutory construction, Supreme Court precedent, and stare decisis, holding that a patent specification must meet the distinct requirements (i) of a written description of the invention, and (ii) of the manner and process of making and using the invention. The court noted that holding otherwise would disturb the law as it had been understood for more than 40 years.

The Federal Circuit majority also rejected Ariad’s argument that the written description requirement does not apply to original claims, and that the only proper purpose of the written description requirement is in determining the priority of amended claims. The court recognized that original claims are part of the specification, but held that this fails to address whether original claim language discloses the subject matter that it claims.

As an example of an original claim that would not satisfy the written description requirement, the court proposed a generic claim that includes a vast genus of chemical compounds, but a specification that describes only a limited number of species. Relying on its own precedent, the court held that a sufficient description of a genus requires the disclosure of either a representative number of species, or structural features common to the members of the genus so that one of skill in the art could “visualize or recognize” its members.

The majority went on to affirm the appropriate standard for the written description requirement as whether the disclosure of the application reasonably conveys to those skilled in the art that the inventor had possession of the claimed subject matter as of the filing date of the patent. Recognizing that the term “possession” is not particularly enlightening, the court stated that “the test requires an objective inquiry into the four corners of the specification from the perspective of a person of ordinary skill in the art.” The court went on to state that this is a factual inquiry that varies from case-to-case, and requires that “the specification must describe an invention understandable to that skilled artisan and show that the inventor actually invented the invention claimed.” While the court did not offer any bright-line tests, it noted a few principles applicable in all cases, including that “a description that merely renders the invention obvious does not satisfy the requirement.”

As a policy issue, Ariad suggested that a separate written description requirement would disadvantage universities, which often are involved only in basic research and lack the resources to work out practical applications of their discoveries. The court dismissed this argument, stating that mere “research hypotheses” do not warrant patent protection; instead, the court held, such protection is limited to those that actually conceive the complete and final invention and disclose it to the public. The court further held that the written description requirement achieves the right balance by giving the incentive to invent without preempting downstream research.
Judge Newman provided additional views, emphasizing “the overriding policy of patent systems requires both written description and enablement, and it is less critical to decide which statutory clause applies in a particular case, than to assure that both requirements are met.” In a concurring opinion, Judge Gajarsa stated that the patent statute is less than clear, and joined the majority opinion as providing “a reasonable interpretation” of the statute.

In dissent, Judge Linn argued that the majority’s clarified “possession” standard still failed to distinguish the test for written description from that of enablement, and suggested that the examples of invalid genus claims offered by the majority would still be invalid under an enablement analysis. In a separate dissent, Judge Rader faulted the majority’s reading of “unambiguous” statutory language, and rebuked the majority for declaring itself the arbiter of what is the right balance between upstream and downstream innovation. Judge Rader warned of the unintended consequences of such “judicial adventurism,” suggesting that under the majority’s holding mere improvements would invalidate genus patents.

For more information about the decision or any other matter raised in this Client Alert, please contact Sharon Israel, Gary Hnath and Michael Word.

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