Couldn't find this anywhere, so made it myself, its a group that excludes all RFC1918 addressing and contains all other IPv4 addresses. It includes RFC3330 but I don't think that will concern most people.
object-group network INTERNET
network-object 0.0.0.0 248.0.0.0
network-object 8.0.0.0 254.0.0.0
network-object 11.0.0.0 255.0.0.0
network-object 12.0.0.0 252.0.0.0
network-object 16.0.0.0 240.0.0.0
network-object 32.0.0.0 224.0.0.0
network-object 64.0.0.0 192.0.0.0
network-object 128.0.0.0 224.0.0.0
network-object 160.0.0.0 248.0.0.0
network-object 168.0.0.0 252.0.0.0
network-object 172.0.0.0 255.240.0.0
network-object 172.32.0.0 255.224.0.0
network-object 172.64.0.0 255.192.0.0
network-object 172.128.0.0 255.128.0.0
network-object 173.0.0.0 255.0.0.0
network-object 174.0.0.0 254.0.0.0
network-object 174.0.0.0 254.0.0.0
network-object 176.0.0.0 240.0.0.0
network-object 192.0.0.0 255.128.0.0
network-object 192.128.0.0 255.224.0.0
network-object 192.160.0.0 255.248.0.0
network-object 192.169.0.0 255.0.0.0
network-object 192.170.0.0 255.254.0.0
network-object 192.172.0.0 255.252.0.0
network-object 192.176.0.0 255.240.0.0
network-object 192.192.0.0 255.192.0.0
network-object 193.0.0.0 255.0.0.0
network-object 194.0.0.0 254.0.0.0
network-object 196.0.0.0 252.0.0.0
network-object 200.0.0.0 248.0.0.0
network-object 208.0.0.0 240.0.0.0
network-object 224.0.0.0 224.0.0.0