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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
30,434 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 167.150.217.0/24 | 256 | ARIN |  US | 2nd Aug 1993 |
| 167.150.218.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.221.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.222.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.226.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.228.0/22 | 1k | ARIN | US | 2nd Aug 1993 |
| 167.150.23.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.232.0/23 | 512 | ARIN | US | 7th Nov 2025 |
| 167.150.234.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.240.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.248.0/21 | 2k | ARIN | US | 2nd Aug 1993 |
| 167.150.28.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.29.0/24 | 256 | ARIN | US | 28th Oct 2025 |
| 167.150.30.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.32.0/19 | 8.2k | ARIN | US | 2nd Aug 1993 |
| 167.150.72.0/21 | 2k | ARIN | US | 2nd Aug 1993 |
| 167.150.8.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.80.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.87.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.88.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.92.0/22 | 1k | ARIN | US | 2nd Aug 1993 |
| 167.150.98.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.151.0.0/16 | 65.5k | ARIN | US | 2nd Aug 1993 |
| 167.152.0.0/16 | 65.5k | ARIN | US | 2nd Aug 1993 |
| 167.156.0.0/16 | 65.5k | ARIN | US | 6th Aug 1993 |
| 167.158.0.0/16 | 65.5k | ARIN | US | 9th Aug 1993 |
| 167.163.0.0/16 | 65.5k | ARIN | US | 11th Aug 1993 |
| 167.17.88.0/21 | 2k | ARIN | US | 8th Aug 2025 |
| 167.178.0.0/16 | 65.5k | ARIN | US | 17th Jul 2018 |
| 167.180.0.0/16 | 65.5k | ARIN | US | 9th Sept 1993 |
| 167.182.128.0/17 | 32.8k | ARIN | US | 10th Sept 1993 |
| 167.185.0.0/16 | 65.5k | ARIN | US | 13th Sept 1993 |
| 167.190.0.0/16 | 65.5k | ARIN | US | 21st Sept 1993 |
| 167.202.0.0/17 | 32.8k | ARIN | US | 27th Sept 1993 |
| 167.202.128.0/18 | 16.4k | ARIN | US | 27th Sept 1993 |
| 167.202.224.0/19 | 8.2k | ARIN | US | 27th Sept 1993 |
| 167.213.0.0/16 | 65.5k | ARIN | US | 12th Oct 1993 |
| 167.214.0.0/16 | 65.5k | ARIN | US | 12th Oct 1993 |
| 167.22.0.0/16 | 65.5k | ARIN | US | 20th Apr 1993 |
| 167.221.0.0/16 | 65.5k | ARIN | US | 21st Oct 1993 |
| 167.224.48.0/21 | 2k | ARIN | US | 25th Oct 1993 |
| 167.224.68.0/22 | 1k | ARIN | US | 25th Oct 1993 |
| 167.224.72.0/21 | 2k | ARIN | US | 25th Oct 1993 |
| 167.226.0.0/16 | 65.5k | ARIN | US | 1st Jun 2018 |
| 167.228.0.0/16 | 65.5k | ARIN | US | 1st Nov 1993 |
| 167.234.0.0/19 | 8.2k | ARIN | US | 7th Aug 2026 |
| 167.234.32.0/22 | 1k | ARIN | US | 10th Nov 1993 |
| 167.234.37.0/24 | 256 | ARIN | US | 1st Jul 2026 |
| 167.247.128.0/17 | 32.8k | ARIN | US | 19th Nov 1993 |
| 167.247.64.0/20 | 4.1k | ARIN | US | 19th Nov 1993 |