Summary

  • The primary, allocatable variants and blocked variants form one RZ-LGR variant-string-set.
  • For a proposed primary that is not already an existing gTLD, changing which member is primary can change the allocatable and blocked subsets without changing the total number of strings.

ICANN’s 2026 Applicant Guidebook says the RZ-LGR calculates the variants of a primary string and assigns each a disposition: allocatable or blocked. Together, the primary and both variant subsets form a variant-string-set.

For an existing gTLD, the existing string is the primary against which that set is calculated. The choice discussed here concerns a proposed primary that is not already an existing gTLD.

For a proposed primary that is not already an existing gTLD, selecting a different member of its variant-string-set as the primary does not change the total number of strings in the set. It may, however, change the partition: a string’s place in the allocatable or blocked subset can differ with the chosen primary.

ICANN tells applicants to consider the corresponding allocatable and blocked variants when selecting the primary. Its LGR Tool can be used to determine allocatable variants for a primary string.

BTW recommends comparing the RZ-LGR output for every viable primary choice before freezing the application inventory, and recording how the two subsets differ. That is editorial operating guidance, not an additional ICANN requirement.

Sources