Some uses of a copyrighted work are considered fair use—that is, the use may infringe but the infringement is excused because the work is being used for a transformative purpose such as research, scholarship, criticism or journalism. When determining whether an infringement should be excused on the basis of fair use, a court will use several factors including the purpose and character of the use, amount and substantiality of the portion borrowed, and effect of the use on the market for the copyrighted material.
It’s important to understand that fair use is a defense rather than an affirmative right. This means that a particular use only gets established as a fair use if the copyright owner decides to file a lawsuit and the court upholds the fair use defense. There is, therefore, no way to find out in advance whether something will or won’t be considered a fair use. Of course, if the copyright owner is willing to grant permission for the use, then the uncertainty surrounding the use goes away. For this reason, most people who propose to use a copyrighted work do what they can to obtain permission, and only rely on the fair use defense if permission is not granted or the copyright owner can’t be located.
A person who infringes a copyright but has good reason to genuinely believe that the use is a fair use is known as an innocent infringer. Innocent infringers usually don’t have to pay any damages to the copyright owner, but do have to cease the infringing activity or pay the owner for the reasonable commercial value of that use.
Related terms: archival copies; fair use, defined; innocent infringement of copyright.