ICANN

 ICANN  is a global organization that is responsible for running the Domain Name Service root name servers and is also responsible for the assignment of IPv4 and IPv6 addresses.

The rules and administration of TLDs is a secondary priority but also one that is it's primary revenue generator which some consider a source of conflict.

It is also responsible for the sending of emails when domain contact information changes which can be a problem as documented in https://levels.io/icann-mafia/.