A sponsored top-level domain is a generic top-level domain proposed by an independent agency, with that agency establishing and enforcing rules restricting the eligibility of registrants to use the TLD. For example, the .aero TLD is sponsored by the Société Internationale de Télécommunications Aéronautiques, who limits registrations to members of the air-transport industry.

Current sponsored TLDs - eligibility - sponsors:

• .aero - members of the air-transport industry - Société Internationale de Télécommunications Aéronautiques .
• .coop - cooperative associations - Dot Cooperation LLC
• .jobs - employment-related sites
• .museum - museums - Museum Domain Management Association
• .pro - credentialed professionals and related entities - Registry Services Corporation
• .travel - travel agents, airlines, hoteliers, tourism bureaus, etc. - The Travel Partnership

Pending sponsored TLDs:

• .post - postal agencies and similar businesses - Universal Postal Union
• .mobi - mobile devices and services for them

There are also non-sponsored generic TLDs which are restricted by other criteria, including .edu (United States accredited colleges), .mil (the United States military), .gov (the United States government), .int (organisations formed by international treaty), and .biz (businesses engaging in commerce on the internet).