Reserved Names (Blocked Names)

Reserved names are labels a registry holds back from open registration. The reasons vary: some are premium names set aside to sell at a higher price, some are blocked for policy or legal reasons (geographic terms, registrar names, ICANN-mandated strings), and some sit on a collision-avoidance list to prevent clashes with internal network names. The reserved list is specific to each TLD and set by its operator under ICANN rules, which is why a name can be available in one TLD but unregisterable in another. Reservation happens entirely at the registry layer of the traditional system, before a name ever becomes a registrant's — and so before it could be tokenized. Source: ICANN TLD listings.