Exist any closed domain zones?
There are cases of new top-level domains (TLD) that allowed open registration and later became bankrupt, leading to the disappearance of the domain and its zone.

There is a growing opposition to the registration of closed domain name zones from both companies and individual internet users, including notable ones such as Microsoft. The majority of experts, including those at Microsoft, argue that companies should only be allowed to close domains that feature their brand names.

Conversely, general-purpose domain zones should remain open and provide domain registration services to other users. It has been proposed that applications for closed general-purpose domains be canceled and that applicants reimburse all related registration costs. Allowing closed domains of general importance could lead companies to monopolize entire industries on the internet and goes against the principle of keeping domains accessible to everyone.

It is crucial to maintain the availability of domains as a limited resource and ensure that they remain open and available to all. This concept aligns with the original purpose of the creation of domains and the internet: to connect people and ideas.

In the distant year of 2012, large European companies began questioning the purpose and potential impact of creating closed domains on the health of the internet. Today, there are many such domain zones that are heavily criticized for impeding businesses. It begs the question: why create a zone that is only assigned to a specific business or product line?

Interestingly, between 2015 and 2016, most of these domains were sold at general auctions, resulting in 80% of them being terminated. This further highlights the potential risks and drawbacks of creating closed domains, as they may prove to be unnecessary and unsustainable in the long run.

consider the potential implications and consequences of any actions taken in the realm of the internet and domains, as it has become an integral part of our daily lives and global economy. Innovation and progress should be prioritized, while also keeping in mind the principles of accessibility, fairness, and sustainability.

Recently, I learned about a significant decline in sales for the .io domain zone in 2022. In quantitative terms, sales fell by six times and by eight times in monetary terms. The reason behind this decline was that sites using .io domains are under strain.

The concerning issue with country-specific domain zones is that they are at risk of being deleted if there are changes to the name or legal status of the territory they represent. This has been witnessed in various cases such as the .an domain zone of the Antilles before the islands gained partial or complete independence from the Netherlands, the .bu domain zone of Burma before it was renamed Myanmar, and the .cs domain zone of Serbia and Montenegro before the collapse. The .io domain zone is also likely to face the same fate, and discussions regarding its removal are already underway.

While there is still a possibility that it won't be canceled, the chances of a positive outcome for the .io domain zone don't seem promising based on previous cases. This emphasizes the importance of considering the potential risks and limitations associated with domain zones when choosing a domain for your website or business.

Closed-TLDs are top-level domains that have highly restricted registration policies, usually managed by a specific authority or organization. These TLDs are designed to serve a particular purpose or community, and access is typically limited to specific entities or individuals.

1. .gov (Government): The .gov TLD is reserved exclusively for use by government entities in the United States. The registration and management of .gov domains is controlled by the General Services Administration (GSA), ensuring that only legitimate government agencies can register and use these domains.

2. .mil (Military): Similar to .gov, the .mil TLD is reserved for use by the United States military. The Department of Defense oversees the registration and administration of .mil domains, maintaining a tight control over this domain space.

3. .edu (Education): The .edu TLD is restricted to accredited post-secondary educational institutions, primarily in the United States. The administration of .edu domains is managed by EDUCAUSE, a non-profit organization that ensures the integrity and purpose of this domain space.

4. .int (International Organizations): The .int TLD is reserved for use by international organizations, such as the United Nations, the European Union, and other intergovernmental entities. The registration and management of .int domains are controlled by the Internet Assigned Numbers Authority (IANA).

Sponsored Top-Level Domains (sTLDs):
Sponsored top-level domains are a type of closed domain zone where the TLD is sponsored by a specific organization or industry group. These sTLDs have their own set of registration policies and eligibility criteria that are enforced by the sponsoring entity.

1. .aero (Air Transport Industry): The .aero TLD is sponsored by the Société Internationale de Télécommunications Aéronautiques (SITA), the world's leading specialist in air transport communications and information technology. Only entities within the air transport industry, such as airlines, airports, and aviation-related organizations, can register .aero domains.

2. .coop (Cooperatives): The .coop TLD is sponsored by the International Cooperative Alliance, a non-governmental organization that represents cooperatives worldwide. Registration in the .coop domain space is limited to organizations that meet the criteria for being a cooperative business.

3. .museum (Museums): The .museum TLD is sponsored by the Museum Domain Management Association, which represents museums and cultural institutions globally. Registration in .museum is restricted to organizations that meet the eligibility requirements for being a museum or related cultural entity.

Closed domain zones, whether Closed-TLDs or sTLDs, provide a level of control and regulation over their respective domain spaces, ensuring that they are used for their intended purposes and by the appropriate entities. However, as you mentioned, there have been cases where new TLDs with open registration policies later became bankrupt or abandoned, leading to the disappearance of the entire domain zone.