There are various policy-making processes relating to each of the IANA registries, grounded in the various communities most directly related to the specific IANA registry in question.
The rules or policies under which the IANA operator makes changes to the IP address and Autonomous System Number registries (including allocations to the Regional Internet Registries) are discussed and agreed upon by consensus in the five RIR communities. Whenever a change to these policies is required, a common policy proposal will be entered into each of the five RIR community policy development processes. Learn about the RIPE Policy Development Process (PDP)
Following the same bottom-up and inclusive process that is used to make regional policy, each RIR community has the chance to discuss and comment on the proposed policy change and reach consensus.
Once all five RIR communities have reached consensus on exactly the same policy text, it will be passed on to IANA in order to be implemented.
An organisation called the Number Resource Organization Number Council (NRO NC) was established in 2004 to oversee the development of global policies, and to ensure that the global policy development process (including specific policy development processes in each RIR community) is followed before a new global policy is accepted. The NRO NC is made up of three community representatives from each RIR region (fifteen in total).
The NRO NC also fills the role of the Address Supporting Organization Address Council (ASO AC), which, under an MoU signed between the NRO and ICANN in 2004, reviews global IP address policies and makes recommendations to the ICANN Board on implementation of those policies.
There is no practical role for the IANA steward (currently the NTIA) in this policy development process. Once the NRO Number Council is happy that the global policy processes have been followed and consensus achieved, the Number Council (in their role as the ASO Address Council) pass the new policy to the ICANN Board, who will ratify proposed global policies in accordance with the Global Policy Development Process, using review procedures as determined by ICANN.