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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
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Countries with unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,461 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.140.198.0/24 | 256 | ARIN |  US | 12th Jul 1993 |
| 198.140.199.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.200.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.205.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.206.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.207.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.208.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.209.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.210.0/24 | 256 | ARIN | US | 25th Jun 2013 |
| 198.140.212.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.214.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.215.0/24 | 256 | ARIN | US | 12th Jul 1993 |
| 198.140.218.0/23 | 512 | ARIN | US | 13th Jul 1993 |
| 198.140.220.0/23 | 512 | ARIN | US | 13th Jul 1993 |
| 198.140.223.0/24 | 256 | ARIN | US | 15th Jul 1993 |
| 198.140.225.0/24 | 256 | ARIN | US | 15th Jul 1993 |
| 198.140.226.0/24 | 256 | ARIN | US | 15th Jul 1993 |
| 198.140.227.0/24 | 256 | ARIN | US | 15th Jul 1993 |
| 198.140.229.0/24 | 256 | ARIN | US | 16th Jul 1993 |
| 198.140.231.0/24 | 256 | ARIN | US | 19th Jul 1993 |
| 198.140.233.0/24 | 256 | ARIN | US | 19th Jul 1993 |
| 198.140.234.0/23 | 512 | ARIN | US | 19th Jul 1993 |
| 198.140.236.0/23 | 512 | ARIN | US | 19th Jul 1993 |
| 198.140.238.0/24 | 256 | ARIN | US | 19th Jul 1993 |
| 198.140.24.0/23 | 512 | ARIN | US | 16th Apr 1993 |
| 198.140.243.0/24 | 256 | ARIN | US | 19th Jul 1993 |
| 198.140.244.0/24 | 256 | ARIN | US | 16th Jul 1993 |
| 198.140.245.0/24 | 256 | ARIN | US | 16th Jul 1993 |
| 198.140.246.0/23 | 512 | ARIN | US | 15th Jul 1993 |
| 198.140.248.0/23 | 512 | ARIN | US | 15th Jul 1993 |
| 198.140.250.0/23 | 512 | ARIN | US | 22nd Jun 1993 |
| 198.140.252.0/23 | 512 | ARIN | US | 22nd Jun 1993 |
| 198.140.254.0/24 | 256 | ARIN | US | 22nd Jun 1993 |
| 198.140.48.0/22 | 1k | ARIN | US | 16th Apr 1993 |
| 198.140.52.0/23 | 512 | ARIN | US | 16th Apr 1993 |
| 198.140.54.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.140.55.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.140.56.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.140.57.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.140.58.0/23 | 512 | ARIN | US | 16th Apr 1993 |
| 198.140.64.0/19 | 8.2k | ARIN | US | 13th Sept 1993 |
| 198.140.96.0/20 | 4.1k | ARIN | US | 13th Sept 1993 |
| 198.145.35.0/24 | 256 | ARIN | US | 28th May 1996 |
| 198.145.37.0/24 | 256 | ARIN | US | 28th May 1996 |
| 198.145.44.0/23 | 512 | ARIN | US | 20th Jul 2023 |
| 198.147.128.0/24 | 256 | ARIN | US | 25th May 1993 |
| 198.147.129.0/24 | 256 | ARIN | US | 25th May 1993 |
| 198.147.130.0/23 | 512 | ARIN | US | 25th May 1993 |
| 198.147.132.0/23 | 512 | ARIN | US | 25th May 1993 |
| 198.147.134.0/24 | 256 | ARIN | US | 28th May 1993 |