Intellectual Property Law

Sue L. Robinson: Heightened Evidentiary Burden Under the Doctrine of Equivalents?

By Karen E. Keller, Andrew A. Lundgren et al.

Last week, district judge Sue L. Robinson rejected a novel argument concerning the evidentiary burden on infringement under the doctrine of equivalents. Defendant claimed that, because it held a license to certain compounds under one patent, plaintiff had to show equivalency under its own patent by clear and convincing evidence. After noting that defendant "freely admits that it cannot cite a case requiring infringement to be proven" under this standard, the Court declined to upset the traditional approach:

"The court finds defendant's position untenable and declines to be the first (and only) court to depart from an extended history of patent infringement jurisprudence applying the preponderance of the evidence standard."

It will be interesting to see whether defendant, as acknowledged by the Court, will pursue its appeal of this novel question.

Siemens Medical Solutions USA, Inc. v. Saint-Gobain Ceramics & Plastics, Inc., C.A. No. 07-190-SLR (D. Del. May 15, 2009) (Robinson, J.).

Full post as published by Delaware IP Law Blog on May 22, 2009 (boomark / email).