On Sep. 18, 2024, Federal Circuit vacated District court’s judgment and remanded the case in which district court determined, sua sponte that claims of U.S. Patent 10,842,780 are invalid under 35 U.S.C. § 101.

 

In Astellas Pharma, Inc. v. Sandoz Inc., Astellas Pharma appealed a decision by the U.S. District Court for the District of Delaware. The court ruled that claims 5, 20, and 25 of Astellas’s U.S. Patent No. 10,842,780 (related to sustained-release formulations of mirabegron, marketed as Myrbetriq® for overactive bladder treatment) were invalid under 35 U.S.C. § 101 for being directed to an ineligible natural law. This case is centered around a key principle in the U.S. judicial system: the party presentation principle.

 

The Federal Circuit highlighted that the district court overstepped its bounds by addressing a patent eligibility issue under 35 U.S.C. § 101, despite neither party raising it as a point of contention. In U.S. patent litigation, the presiding court is supposed to focus on the issues brought forth by the litigants. By independently deciding on § 101 without it being part of the dispute, the district court committed an abuse of discretion. The Federal Circuit referred to precedents such as Greenlaw v. United States and United States v. Sineneng-Smith, which affirm that courts should not adjudicate beyond what the parties present.

 

In this case, Sandoz challenged the validity of Astellas’s patent under 35 U.S.C. § 112, particularly on the grounds of enablement and written description, but did not raise § 101 patent eligibility. Nonetheless, the district court invalidated the patent based on § 101, prompting Astellas to appeal. The Federal Circuit reaffirmed the statutory presumption of patent validity under 35 U.S.C. § 282. Under this framework, patent challengers bear the burden of proving invalidity by clear and convincing evidence. In the absence of an explicit challenge to subject matter eligibility under § 101, the district court had no authority to independently address that issue. The court underscored that patent eligibility under § 101 is not a “threshold issue” that must be examined sua sponte, but must be argued by the parties for the court to consider.

 

The Federal Circuit vacated the district court’s judgment, finding that the decision to invalidate the patent on § 101 grounds was procedurally flawed. The case was remanded to the district court to focus on the original issues raised by the parties—specifically, whether the patent was invalid under 35 U.S.C. § 112 for lack of enablement or insufficient written description.