The term sponsored top-level domain is derived from the fact that these domains are based on "theme" concepts proposed by private agencies or organizations that establish and enforce rules restricting the eligibility of registrants to use the TLD. For example, the .aero TLD is sponsored by the Société Internationale de Télécommunications Aéronautiques, which limits registrations to members of the air-transport industry.
.eu is the country code top-level domain (ccTLD) for the European Union, and organisations and citizens of EU member states, which was launched on 7 December 2005.