This article examines the notion of fan labor through Disney park fans’ work of “Disney scholarship” and “Disney history,” as well as the extent to which such data might be used by academic researchers. While it provides unavoidable entry points to academic investigations of Disney theme parks and their history, this body of knowledge reveals underlying motivations specific to fandom’s social and cultural economy. A brief history of Disney park fandom will show how fan-created works of “Disney scholarship” evidence popular expertise in often disregarded areas of culture, as well as processes of fan labor that complicate the traditional amateur/professional binary. For all their claims to professionalism, fans generally regard paid labor with suspicion and trade fan-collected data by rules typical of a gift economy. As self-styled Disney historians morph into Disney custodians, they reveal underlying motivations that help make sense of the data they produce: in their struggle to preserve Walt-era attractions and protect the park from the corporation’s commercialism, fans reveal a set of prescriptive attitudes on how to engage with the parks that inform their practices as park chroniclers. This is especially evident in controversies over proposed attraction updates, as fans set out to promote a historically and aesthetically discerning appreciation of Disney products, outside the imperatives of commercial culture.