What Is Public Domain Footage?
Public domain footage is video no longer, or never, protected by copyright, so anyone may use it without permission. It is not the same as free stock footage.
A work enters the public domain when its copyright ends, or it never had one, as with many works made by the US federal government. The U.S. Copyright Office says that for works created from 1978, copyright lasts the author’s life plus 70 years, and for anonymous works and works made for hire 95 years from publication or 120 from creation, whichever ends first; works published before 1978 depend on several factors. Other countries count differently.
Free stock footage is something else. A site such as Pexels gives its videos under its own licence: free to use, no credit needed, but with rules, such as not showing identifiable people in a bad light and not selling unaltered copies. Licensed is not public domain.
For a creator, public domain footage, such as old newsreels, archive films and NASA material, is legal to use. On YouTube it is still subject to the reused content policy: an archive clip posted as it is adds nothing of yours. Explain it, narrate it or build a story around it.
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