On July 31 1999 the first production IPv6 prefix was assigned by ARIN to ESnet (2001:400::/35). Since then several sites previously connected via the 6bone network have received their own IPv6 subnet.
This address list is no longer maintained due to the successful growth of the IPv6 network. Please refer to the IANA TLA list for an overview of the addresses assigned to the various Regional Internet Registries (RIRs). More detailed information can be obtained from RIR websites and 'whois' tools.