So let’s consider your research for your film. Perhaps you need footage to illustrate a point and you don’t have anything relevant in your own footage or what is commonly referred to as rushes. Archive footage might work, or a news article, or maybe it’s a police surveillance camera. These are all called third-party materials, and there are many categories. It’s called third-party because you literally don’t own the material. You can’t just take anyone’s artwork whether writing, photographs or clips from a TV show to illustrate your point, without first considering the ownership of that work.