Right to light is a form of easement in English law that gives a long-standing owner of a building with windows a right to maintain the level of illumination. The right was traditionally known in the Anglo-American common law as the doctrine of "ancient lights". In England, the rights to ancient lights are most usually acquired under the Prescription Act 1832. But the doctrine died out in the American common law during the 19th century, and is generally no longer recognized in the United States. Japanese law provides for a comparable concept known as nisshōken (literally "right to sunshine").