Allocated but unannounced space
Every block here was allocated or assigned by a regional internet registry, and none of them appeared in any routing table we collected at our last snapshot — neither as a route of their own, nor covered by a larger announcement, nor carved up into more specifics.
“Unannounced” does not mean “unused”
Plenty of allocated space is deliberately kept off the public internet: private interconnects, lab and lawful-intercept ranges, networks reachable only inside one operator, and space held in reserve. Some of it is announced somewhere our collectors cannot see, which is a limit of our vantage points rather than a fact about the block.
It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today. Nothing on this page means a block is unallocated, available, or free to announce.
Browse by registry
Browse by country
Countries with the most unannounced blocks, largest first.
Unannounced blocks
85,256 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.99.137.0/24 | 256 | ARIN |  US | 9th Apr 1993 |
| 198.99.139.0/24 | 256 | ARIN | US | 9th Apr 1993 |
| 198.99.140.0/24 | 256 | ARIN | US | 9th Apr 1993 |
| 198.99.142.0/24 | 256 | ARIN | US | 9th Apr 1993 |
| 198.99.147.0/24 | 256 | ARIN | US | 13th Apr 1993 |
| 198.99.148.0/24 | 256 | RIPE NCC |  CH | 1st Sept 1993 |
| 198.99.149.0/24 | 256 | ARIN | US | 2nd Jul 2026 |
| 198.99.150.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.151.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.152.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.153.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.154.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.160.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.161.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.162.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.163.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.99.164.0/24 | 256 | ARIN | US | 15th Apr 1993 |
| 198.99.165.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.166.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.167.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.168.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.170.0/24 | 256 | ARIN |  CA | 16th Apr 1993 |
| 198.99.172.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.174.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.175.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.178.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.180.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.181.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.183.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.185.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.186.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.187.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.99.191.0/24 | 256 | ARIN | US | 20th Apr 1993 |
| 198.99.192.0/24 | 256 | ARIN | US | 20th Apr 1993 |
| 198.99.197.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.99.198.0/23 | 512 | ARIN | US | 23rd Apr 1993 |
| 198.99.200.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.99.201.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.99.202.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.99.203.0/24 | 256 | ARIN | US | 11th Jun 1993 |
| 198.99.204.0/23 | 512 | ARIN | US | 23rd Apr 1993 |
| 198.99.206.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.99.207.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.99.208.0/24 | 256 | ARIN | US | 27th Apr 1993 |
| 198.99.211.0/24 | 256 | ARIN | US | 27th Apr 1993 |
| 198.99.212.0/24 | 256 | ARIN | US | 27th Apr 1993 |
| 198.99.213.0/24 | 256 | ARIN | US | 27th Apr 1993 |
| 198.99.214.0/24 | 256 | ARIN | US | 27th Apr 1993 |
| 198.99.215.0/24 | 256 | ARIN | US | 27th Apr 1993 |
| 198.99.216.0/24 | 256 | ARIN | US | 27th Apr 1993 |