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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
30,419 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 13.129.0.0/16 | 65.5k | ARIN |  US | 25th Apr 1986 |
| 13.131.0.0/16 | 65.5k | ARIN | US | 25th Apr 1986 |
| 13.132.0.0/15 | 131k | ARIN | US | 25th Apr 1986 |
| 13.136.0.0/14 | 262k | ARIN | US | 25th Apr 1986 |
| 13.145.0.0/16 | 65.5k | ARIN | US | 25th Apr 1986 |
| 13.147.0.0/16 | 65.5k | ARIN | US | 25th Apr 1986 |
| 13.148.0.0/15 | 131k | ARIN | US | 25th Apr 1986 |
| 13.150.0.0/15 | 131k | ARIN | US | 19th Dec 2022 |
| 13.153.0.0/16 | 65.5k | ARIN | US | 25th Apr 1986 |
| 13.155.0.0/16 | 65.5k | ARIN | US | 25th Apr 1986 |
| 13.156.0.0/15 | 131k | ARIN | US | 25th Apr 1986 |
| 13.161.0.0/16 | 65.5k | ARIN | US | 25th Apr 1986 |
| 13.163.0.0/16 | 65.5k | ARIN | US | 25th Apr 1986 |
| 13.164.0.0/15 | 131k | ARIN | US | 25th Apr 1986 |
| 13.184.0.0/13 | 524k | ARIN | US | 28th Sept 2021 |
| 13.96.0.0/13 | 524k | ARIN | US | 26th Mar 2015 |
| 130.1.0.0/16 | 65.5k | ARIN | US | 25th Sept 1992 |
| 130.10.0.0/16 | 65.5k | ARIN | US | 25th Sept 1992 |
| 130.103.0.0/16 | 65.5k | ARIN | US | 18th Jul 1988 |
| 130.106.0.0/16 | 65.5k | ARIN | US | 20th Jul 1988 |
| 130.12.105.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.107.0/24 | 256 | ARIN | US | 17th Oct 2025 |
| 130.12.108.0/24 | 256 | ARIN | US | 13th Oct 2025 |
| 130.12.109.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.110.0/24 | 256 | ARIN |  CA | 8th Oct 2025 |
| 130.12.124.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.127.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.148.0/22 | 1k | ARIN | US | 8th Oct 2025 |
| 130.12.157.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.158.0/24 | 256 | ARIN | US | 17th Oct 2025 |
| 130.12.174.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.175.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.184.0/22 | 1k | ARIN | US | 8th Oct 2025 |
| 130.12.188.0/24 | 256 | ARIN | CA | 8th Dec 2025 |
| 130.12.189.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.192.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.193.0/24 | 256 | ARIN | US | 14th Oct 2025 |
| 130.12.206.0/24 | 256 | ARIN | US | 8th Dec 2025 |
| 130.12.208.0/24 | 256 | ARIN | US | 9th Oct 2025 |
| 130.12.212.0/22 | 1k | ARIN | US | 8th Oct 2025 |
| 130.12.220.0/22 | 1k | ARIN | US | 8th Oct 2025 |
| 130.12.224.0/22 | 1k | ARIN | US | 8th Oct 2025 |
| 130.12.232.0/22 | 1k | ARIN | US | 8th Oct 2025 |
| 130.12.236.0/23 | 512 | ARIN | US | 8th Oct 2025 |
| 130.12.239.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.24.0/22 | 1k | ARIN | US | 8th Oct 2025 |
| 130.12.248.0/24 | 256 | ARIN | US | 8th Oct 2025 |
| 130.12.249.0/24 | 256 | ARIN | CA | 24th Dec 2025 |
| 130.12.252.0/23 | 512 | ARIN | US | 8th Oct 2025 |
| 130.12.28.0/24 | 256 | ARIN | US | 8th Oct 2025 |