How can I find out if a movie/series is still restricted by copyright?

Question

My understanding is that determining copyright is not always as simple as adding a number of years to the date a movie was first released/a series was first aired.

What resources are there to determine if a movie/series is still under copyright or not?

I have classic movies including silent movies in mind, hence the tag. I couldn't find any other applicable tags. Perhaps 'legal-status' which could in future include banned movies and other interesting tidbits?

Answer 1

It depends on the country and the individual factors can be complicated. But the easiest way is to check if it already appears on a list of public domain films.

For example, Wikipedia's "List of films in the public domain in the United States" has plenty of information about determining public domain status, including:

If a film appears on the list below, there is a high probability it has lost some or all of its United States copyright protection (or in the case of U.S. government films, was never protected by copyright).

There is no single method for determining if a film, or parts of it, is in the public domain. There are several methods that can be used to document a film’s public domain status.

The Internet Archive has feature films for download and streaming, and have a FAQ to help determine whether a film is in the public domain.