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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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.
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Countries with unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,476 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.45.0.0/21 | 2k | ARIN |  US | 5th Nov 1993 |
| 199.45.8.0/22 | 1k | ARIN | US | 5th Nov 1993 |
| 199.46.64.0/19 | 8.2k | ARIN | US | 14th Mar 1994 |
| 199.47.1.0/24 | 256 | ARIN | US | 8th Nov 1993 |
| 199.47.12.0/23 | 512 | ARIN | US | 8th Nov 1993 |
| 199.47.132.0/22 | 1k | ARIN | US | 6th Oct 2010 |
| 199.47.14.0/24 | 256 | ARIN | US | 8th Nov 1993 |
| 199.47.2.0/24 | 256 | ARIN | US | 8th Nov 1993 |
| 199.47.212.0/22 | 1k | ARIN | US | 15th Oct 2010 |
| 199.47.216.0/22 | 1k | ARIN | US | 15th Oct 2010 |
| 199.47.3.0/24 | 256 | ARIN | US | 8th Nov 1993 |
| 199.47.39.0/24 | 256 | ARIN | US | 9th Sept 2015 |
| 199.47.4.0/22 | 1k | ARIN | US | 8th Nov 1993 |
| 199.47.8.0/22 | 1k | ARIN | US | 8th Nov 1993 |
| 199.48.152.0/22 | 1k | ARIN | US | 25th Oct 2010 |
| 199.48.168.0/24 | 256 | ARIN |  CA | 17th Jan 2018 |
| 199.48.216.0/21 | 2k | ARIN | CA | 2nd Nov 2010 |
| 199.48.60.0/24 | 256 | ARIN | US | 26th Dec 2024 |
| 199.5.128.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.129.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.130.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.131.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.132.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.134.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.135.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.136.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.141.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.5.142.0/23 | 512 | ARIN | US | 14th Dec 1993 |
| 199.5.144.0/23 | 512 | ARIN | US | 14th Dec 1993 |
| 199.5.147.0/24 | 256 | ARIN | US | 14th Aug 2015 |
| 199.5.152.0/23 | 512 | ARIN | US | 14th Dec 1993 |
| 199.5.158.0/24 | 256 | ARIN | US | 15th Dec 1993 |
| 199.5.159.0/24 | 256 | ARIN | US | 15th Dec 1993 |
| 199.5.16.0/21 | 2k | ARIN | US | 13th Sept 1993 |
| 199.5.160.0/24 | 256 | ARIN | US | 15th Dec 1993 |
| 199.5.162.0/24 | 256 | ARIN | US | 17th Dec 1993 |
| 199.5.168.0/24 | 256 | ARIN | US | 15th Dec 1993 |
| 199.5.169.0/24 | 256 | ARIN | US | 15th Dec 1993 |
| 199.5.170.0/24 | 256 | ARIN | US | 16th Dec 1993 |
| 199.5.173.0/24 | 256 | ARIN | US | 2nd Jul 2026 |
| 199.5.174.0/24 | 256 | ARIN | US | 16th Dec 1993 |
| 199.5.175.0/24 | 256 | ARIN | US | 6th Jan 1994 |
| 199.5.176.0/23 | 512 | ARIN | US | 17th Dec 1993 |
| 199.5.178.0/24 | 256 | ARIN | US | 17th Dec 1993 |
| 199.5.179.0/24 | 256 | ARIN | US | 2nd Mar 2021 |
| 199.5.183.0/24 | 256 | ARIN | US | 20th Dec 1993 |
| 199.5.185.0/24 | 256 | ARIN | US | 20th Dec 1993 |
| 199.5.186.0/24 | 256 | ARIN | US | 21st Dec 1993 |
| 199.5.187.0/24 | 256 | ARIN | US | 21st Dec 1993 |
| 199.5.188.0/24 | 256 | ARIN | US | 21st Dec 1993 |