Patent Infringement Opinion Law and Legal Definition

Infringement opinion as used in the context of patents refers to patent attorney’s opinion about the probable outcome of an infringement hearing or trial on whether or not a product or process infringes on an existing patent, or whether or not there is good reason to believe the alleged infringed patent is invalid. Intellectual property attorneys specializing in patent law are often called on to render patent opinions. Opinion letters are reviewed by the courts to determine whether they evidence an adequate foundation based on all the necessary facts, or whether they are conclusory on their face. Counsel’s opinion must be thorough enough, combined with other factors, to instill a belief in the infringer that a court might reasonably hold the patent invalid, not infringed, or unenforceable.