We define an authority model, in the context of CSCW, as the characteristics of the system that determine who has control over objects in the system, and how this control manifests. In this paper we present two natural authority models (free-form and owner-centric) and, employing an empirical study, explore the question "which authority model is best for collaborative, commons-based content authoring?" We discover that the answer varies, depending on whether productivity or user satisfaction is to be the metric of goodness, and likely can not be phrased in absolutes.