Currently all public addresses are being assigned out of 2000::/3. The following are reserved for future (public?) use: 4000::/3, 6000::/3, 8000::/3, a000::/3, c000::/3.
Everything that starts with "f" is a special case, so the vast (vast) majority of address space is cleaved off.
* https://www.iana.org/assignments/ipv6-address-space/ipv6-add...
Currently all public addresses are being assigned out of 2000::/3. The following are reserved for future (public?) use: 4000::/3, 6000::/3, 8000::/3, a000::/3, c000::/3.
Everything that starts with "f" is a special case, so the vast (vast) majority of address space is cleaved off.