Legal Dictionary of Pakistan
Quick lookup for English, Urdu, and Latin legal terms used in Pakistani jurisprudence.
doctrine of equivalents
Patents. A judicially created theory for finding patent infringement when the accused process or product falls outside the literal scope of the patent claims. 0 The doctrine evolved to prevent parties from evading liability for patent infringement by making trivial changes to avoid the literal language of the patent claims. Crater Tank & Mfg. Co. u. Linde Air Prods. Co., 339 U.S. 605, 70 S.Ct. 854 (1950). In determining whether infringement exists under the doctrine, the court must first determine whether "the accused product or process contain[s] an element identical or equivalent to each claimed element of the patented invention." Warner-Jenkinson Co. u. Hilton Davis Chem. Co., 117 S.Ct. 1040, 1054 (1997). Then, if a correspondence is found between the elements of the accused device and of at least one patent claim, infringement under the doctrine turns on (1) whether the accused device substitutes an element that performs the same function, in a substantia
reverse doctrine of equivalents
The doctrine preventing infringement liability when the invention is substantially described by the claims of another's patent but performs the same or similar function in a substantially different way.