Published works by known authors. Seventy years have passed since 1 January of the year following the year in which the author died (or, if there were joint authors, the year in which the author dying last died): Articles 31(1) and (2).
Published works by unknown authors. Seventy years have passed since 1 January of the year following the year in which the work was first disclosed: Article 31(3). (If the author becomes known during this time, the preceding paragraph applies.)
Unpublished works by unknown authors. Seventy years have passed since the date when the work was created, and 25 years have passed since 1 January of the year following the year in which the work was legally disclosed by a person other than the author: Articles 31(7) and 32.
Official works. It is a provision of law, some other legal instrument of state administration, a judicial or authority decision, an authority or other official announcement or document, or a standard or other like provision made obligatory by a legislative act: Article 1(4).
Facts and daily news. It consists of facts or daily news that serves as a basis for press information: Article 1(5).
Folklore. It is an expression of folklore: Article 1(7). (Note, however, that works of an individual and original nature that are inspired by folk art are subject to copyright.)
この著作物がアメリカ合衆国においてパブリックドメインの状態にあることを示すために、アメリカ合衆国のPDタグも貼る必要があります。
