Currently, however, the registration is limited to Turkish individuals for their full name, Companies registered in Turkey, foreigners with a residence in Istanbul until the end of March. After that, all restrictions will be lifted, according to the IHS[1] (a hosting company operating in Turkey)
[1] (Turkish) https://www.ihs.com.tr/istanbul-alan-adi-domain-tescili.html...
> The Central Registry Agency services offered as "open" and "unrestricted", which enable everyone around the world to register a name in the top level domains .istanbul and .ist