Copyright as a rule of evidence

Many copyright doctrines serve to exclude from the copyright regime cases particularly prone to evidentiary complexity. The implicit logic is that, for these cases, the social costs of litigation would likely outweigh the social benefits derived from offering copyright protection in the first place. Doctrines that serve this evidentiary function include some doctrines for which an evidentiary purpose is readily apparent (for example, the requirement that eligible works be fixed in tangible form), and some for which the link is quite subtle (for example, the rule against protecting work that lacks creativity). Understanding these doctrines in this light helps to refine their proper scope and application. It also makes clear a problem facing copyright law more generally: the increasing divergence between the logical justifications for various copyright doctrines and their actual use by courts and commentators.