Fair use is one of the most talked-about aspects of copyright law. At its core, it seeks to balance the exclusive rights of copyright owners and the needs of others to use copyright-protected works. To determine whether a use is fair, judges consider (and lawyers argue) four factors, which are codified in 17 USC §107. The fair use doctrine is deliberately flexible. Each situation must be evaluated individually.
It's important to note that the only people who decide whether a use is fair are federal judges—and they make those decisions only after a dispute is argued before them. So, nobody can tell us in advance whether a use is fair. We must use our best judgment in evaluating fair use. That said, many fair use cases have been decided so we have some guidance about how to interpret the four factors.
Nothing in this guide or the linked resources provides legal advice. These tools are provided for reference, and I hope they help you to understand this interesting area of law.
Fair use is determined by considering these four factors. No single factor determines the outcome; all must all be weighed to reach a decision. Think of each factor as a sliding scale from unfair to fair.
Purpose and character of the use
Nonprofit uses with social benefit are favored. Teaching, scholarship, research, news reporting, criticism, and comment are mentioned in the law as favorable purposes.
Judges also favor uses they consider to be transformative, which is interpreted to mean either:
• the copyright-protected work is used in a new creation that is not merely a reproduction of the original work, for example using portions of a picture in a collage
• the work is used in a new way that the owner would not have brought about, for example scanning books into a database that allows word searches of the texts but does not display large passages of text from the books
Nature of the work used
Use of highly factual material is more likely to be fair than use of very creative work.
Amount of the work used
Judges consider how much of a work was used, and whether the portion used was the heart of the work—the juicy part everyone wants to read, hear, or watch.
Effect on the market for or value of the work used
If a copyright owner would lose revenue because of a use, that use is not likely to be fair. Also, judges consider not just the use at issue, but whether widespread similar uses would harm the market for the original.
It can be challenging that there are few absolutes about what is and is not fair. Rather, fair use is flexible, and determined on a case-by-case basis. To provide guidance, many professional communities have carefully studied their activities in relation to fair use, and developed statements of best practices. While best practices are not law, they do explain why practitioners believe certain activities are fair.