Defending Patent Infringement With 'Ensnarement'

Law360, New York (October 13, 2009, 11:04 AM EDT) -- Recently, in DePuy Spine Inc. v. Medtronic Sofamor Danek, 567 F.3d 1314 (Fed. Cir. June 1, 2009), the United States Court of Appeals for the Federal Circuit considered the patent infringement defense of “ensnarement.”

Ensnarement bars a patentee from asserting a scope of equivalency under the doctrine of equivalents that would encompass or “ensnare” the prior art.

In DePuy Spine, the court held ensnarement is a question of law to be decided by the court and not the jury, likening it to prosecution history estoppel....
To view the full article, register now.