Hi, The IANA IPv4 registry has been updated to reflect the allocation of four /8 IPv4 blocks to ARIN and RIPE NCC in November 2010: 5/8, 23/8, 37/8 and 100/8. You can find the IANA IPv4 registry at: http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xml http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xhtml http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.txt The complete list of IPv4 /8s allocated so far this year is: 1/8 5/8 14/8 23/8 27/8 31/8 36/8 37/8 42/8 49/8 50/8 100/8 101/8 105/8 107/8 176/8 177/8 181/8 223/8 Please update your filters as appropriate. The IANA free pool contains 7 unallocated unicast IPv4 /8s. Regards, Leo Vegoda Number Resources Manager, IANA ICANN