The current patent statutes are structured to grant unambiguous patents that give patent holders a right to exclude and provide the public with ample notice of the patented subject matter. Therefore, courts should interpret the scope of a claim using only the specification and the file history, the very tools used by the patent holder and public to define the bounds of the patent. Unfortunately, limiting statements made abroad can be allowed into evidence, creating a way or accused infringers to evade liability. By permitting judges to admit extrinsic evidence for the purpose of providing clarity to a supposedly already unambiguous patent claim, the Federal Circuit is providing defendants with one more escape route out of the courtroom and onto the streets of infringement. This comment concentrates on the use of foreign extrinsic evidence and the drastic effects it can have on domestic patent litigation.
Brian R. Cheslek, “You Said What?”: A Look at the Influence of Foreign Patent Prosecution on Domestic Infringement Litigation, 3 J. Marshall Rev. Intell. Prop. L. 119 (2003)