Federal Circuit: Lifestream Diagnostics v. Polymer Technologies

Lifestream Diagnostics v. Polymer Technologies (Fed. Cir. 2004) (unpublished opinion).

Lifestream sued Polymer Tech for alleged infringement of its patent on HDL cholesterol testing equipment.  (U.S. Patent No. 5,135,716).  After conducting a Markman hearing, the district court awarded a judgment of noninfringement to Polymer Tech.

On appeal, the Federal Circuit reversed in part.

We hold that reliance by the Patent Office upon arguments mae by the patentee during prosecution is not necessary to find argument-based estoppel.... Because we reverse some of the district court's claim construction, we vacate the court's judgment of noninfringement and remand.