## Facts

- The University of Rochester owned U.S. Patent No. 6,048,850, directed to a method of treating by selectively inhibiting prostaglandin synthesis through inhibition of COX‑2 in humans using a non‑steroidal compound that inhibits COX‑2 but not COX‑1.
- The patent specification described the COX‑2 enzyme and disclosed assays/screening methods to identify selective COX‑2 inhibitors.
- The specification did not disclose any actual compound, or a structurally defined class of compounds, that performed the claimed selective inhibition.
- Pharmaceutical companies marketed selective COX‑2 inhibitor drugs (including products such as celecoxib and valdecoxib).
- Rochester sued for infringement; defendants moved for summary judgment that the patent was invalid under 35 U.S.C. § 112, ¶ 1 for failure to satisfy written description and enablement.
- The district court granted summary judgment of invalidity; Rochester appealed.

## Issues

1. Whether 35 U.S.C. § 112, ¶ 1 includes a written description requirement independent of enablement.
2. Whether a method claim to selective COX‑2 inhibition satisfies written description when the specification discloses only the biological target and screening methods, but no compound (or structurally/otherwise precisely defined class) that achieves the claimed selectivity.

## Decision

- The Federal Circuit affirmed summary judgment that the patent was invalid.
- The court held that § 112, ¶ 1 contains a written description requirement distinct from enablement.
- The court concluded the patent failed written description because it did not provide a “precise definition” identifying any compound (or defined class) that would perform the claimed method.
- The court affirmed invalidity on written description grounds and did not reach enablement.

## Legal Principles

- Section 112, ¶ 1 imposes separate requirements of written description, enablement, and best mode; compliance with one does not establish compliance with the others.
- Written description requires disclosure sufficient to show the inventor had possession of the claimed invention at filing, such that a skilled artisan can recognize the invention’s identity.
- For chemical/pharmaceutical inventions, written description generally requires a “precise definition” (e.g., structure, formula, chemical name, or physical properties), not merely identification of a research goal or a plan for finding compounds that might work.
- Disclosing assays or screening techniques to discover compounds does not, without more, describe the compounds required by broad therapeutic method claims.

## Conclusion

The Federal Circuit held the COX‑2 selective inhibition method claims invalid because the specification described the biological target and how to search for inhibitors, but did not identify any operative compound or defined class, failing the written description requirement under § 112, ¶ 1.


Univ. of Rochester v. G.D. Searle & Co., 358 F.3d 916 (Fed. Cir. 2004)