It is an anonymous work or pseudonymous work and 50 years have passed since the date of its publication
It is a collective audiovisual or photographic work and 50 years have passed since the date of its publication (or creation, whatever date is the latest)
It is another kind of work, and 50 years have passed since the year of death of the author (or last-surviving author)
This image shows a flag, a coat of arms, a seal or some other official insignia. The use of such symbols is restricted in many countries. These restrictions are independent of the copyright status.