Throughout the Islamic world those claiming descent from the Prophet Muhammad (T. seyyid/serif pl. sadat/esraf) were (and are) accorded a special status. This article shows that the process of teseyyud ("seyyidization") not only took place through official awards, but also through appropriation. In the Ottoman Empire registers thus began to be kept of officially recognized sadat. The examination of these, largely un(der)studied, sources argues that the state sometimes employed its capacity to seyyidize for (cultural) political purposes. The article also sheds valuable light on Ottoman policies vis-a-vis tribalism and nomadism