Means-Plus-Function Limitations Are Indefinite Under 35 U.S.C. § 112, ¶ 2 Where A Specially Adapted Computer Is Required, But Patent Does Not Disclose Algorithm

This article previously appeared in Last Month at the Federal Circuit, April 2012

Judges: Newman (dissenting), Linn, Moore (author)

[Appealed from D. Me., Judge Singal]

In Ergo Licensing, LLC v. Carefusion 303, Inc., No. 11-1229 (Fed. Cir. Mar. 26, 2012), the Federal Circuit affirmed the district court's holding that the terms "control means" and "programmable control means" are indefinite because the patent specification failed to disclose any corresponding structure.

Ergo Licensing, LLC ("Ergo") accused Carefusion 303, Inc. ("Carefusion") of infringing claims of U.S. Patent No. 5,507,412 ("the '412 patent"), which relates to an infusion system used to meter and deliver fluids from multiple fluid sources into a patient's body. The infusion system includes adjusting means for controlling the fluid flow from the multiple fluid sources. Prior to the Markman hearing, the parties stipulated that several terms were means-plus-function terms, including the terms