By questions of “canon,” we mean questions of what is fictionally true of some character, story, or world. What is canon is treated as authoritative or official, usually by creators and fans alike. But disputes about canon have arisen as storytellers and publishers have sought to capitalize on the popularity of their characters, churning out more and more stories to meet public demand, and at the same time engaging with growing fan bases. As audiences have become more involved, and as fictional worlds have become messier, the authoritative nature of canon—and who authorizes it—has begun to erode. In this paper, we characterize canon as an article in the evolving relation between authors and audiences. More specifically, we characterize canon as an intangible good, subject to a form of cultural negotiation, resting on a power relation between producers and consumers of fictions. In Part I, we consider the author’s evolving role, and the rights of the creator to a story, character, or world. In Part II, we discuss the emerging activities of fans, particularly as they weigh on issues of canon. In Part III, we discuss canon as being subject to cultural negotiation, highlighting the importance of power dynamics in this negotiation.