These are names that are already registered, but you can request a domain registration under them. The full list of the second level subdomains under .hu is this:* 
List of Second Level Public Subdomains

*Only domain names that are the trademark of the applicant can be chosen under

So, if the name of my company is for example Accountantcompany Ltd., but is already registered, then I can choose or

The name of a second level public domain usually shows what types of companies and organizations should register a domain name under them, but there is no restriction except for the above mentioned

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