In a recent decision, the Federal Circuit held that the district court lacked authority to “disinter” and declare claims invalid where the patent owner had statutorily disclaimed the claims. Sanofi-Aventis U.S., LLC v. Dr. Reddy’s Labs., Inc., 933 F.3d 1367 (Fed. Cir. 2019).

The case concerns the drug cabazitaxel, marketed as Jevtanta®, which is used for treatment of drug-resistant prostate cancers. Sanofi-Aventis (“Sanofi”) own the Orange Book listed 5,847,170 (“the ’170 patent”) and 8,927,592 (“the ’592 patent”) patents, which cover the compound and methods of using cabazitaxel. Fresenius Kabi and others (“Defendants”) filed an ANDA for the drug, and Sanofi sued for infringement on the ’170 and ’592 patents in the district court.

Concurrently, the Patent Trial and Appeal Board (“PTAB”) instituted an inter partes review of the ’592 patent, and eventually held claims 1-5 and 7-20 of the ’592 patent unpatentable as obvious. The Board also denied Sanofi’s motion to amend the claims, but after an appeal the decision was remanded back to the Board. The matter is still pending.

Back at the district court, the case had proceeded through a bench trial. Just prior to the court issuing a final decision, Sanofi filed a statutory disclaimer with the Patent and Trademark Office (“PTO”) on a subset of claims that the PTAB had held obvious. Despite the statutory disclaimer, the district court found that a case or controversy still existed and held the disclaimed claims also invalid as obvious. Sanofi appealed the district court’s jurisdiction over the disclaimed claims.

On appeal, Defendants argued that a case or controversy existed at the time of the decision because Sanofi could amend the claims of the ’592 patent and force Defendants to re-litigate the same validity issues. They further argued that the district court’s decision preserved possible claim or issue preclusion defenses and provided patent certainty for the future.

The Federal Circuit disagreed. It found these arguments to be speculative and immaterial because the disclaimer “[left] the ’592 patent as though the disclaimed claims had never existed.” (internal quotations removed). The Court found that possible enforcement of amended claims as an insufficient basis to establish an imminent case or controversy. The Court further reasoned that Defendants would have “ample opportunity” to raise a claim or issue preclusion defense if necessary.

This case highlights that statutory disclaimer may be another tool used by patent owners to avoid injury at the district court while attempting to resolve matters at the PTAB.