Public domain video is any video that is no longer or never was protected by copyright law and can, therefore, be freely used without permission of any copyright owner. This is not necessarily the same as publicly available video, since many videos can be viewed publicly on Internet websites that are still protected by copyright. Depending on the nature of a video, all or part of it may be in the public domain, while other parts of the video may exist under a separate copyright. Public domain video can be freely used and altered for a variety of purposes.
Much like other aspects of public domain media, public domain video is any video not protected by copyright law. In general, if a video is created that utilizes original content, then it is protected by copyright as the intellectual property of its creator, usually the director or person using the camera. Videos made under contract for a company, however, are typically the property of that company, and this is usually established in the contract between a company and video maker. Once the copyright for a video expires, or if the copyright is freely relinquished, then it becomes a public domain video.
Since this video is not protected under copyright law, it can be freely used without permission by anyone else. It cannot, however, be registered as a copyright by someone else, since it has become free to the public in general. A work that is created as a derivative work, which includes allusions to or aspects of a public domain video, can potentially be protected under copyright. This depends on the nature of the work and the originality of thought and creation presented in the derivative work.
Due to the nature of the video format, as often having both visual and auditory components, it is possible that a public domain video may include content that is not in the public domain. Someone who creates a video montage of moments in favored movies, for example, may include images or content that is protected under copyright, even if the montage itself belongs to the public domain. It is also possible for someone to use music in a video that is owned by someone else, and even if the video was public domain, the music would still be protected under copyright. This can make the exact nature of public domain video somewhat complicated, and full ownership of a video often depends on individual situations and the owners involved.