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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
30,430 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 140.232.164.0/22 | 1k | ARIN |  US | 21st May 1990 |
| 140.232.168.0/21 | 2k | ARIN | US | 21st May 1990 |
| 140.232.176.0/21 | 2k | ARIN | US | 21st May 1990 |
| 140.232.66.0/23 | 512 | ARIN | US | 21st May 1990 |
| 140.232.68.0/22 | 1k | ARIN | US | 21st May 1990 |
| 140.232.72.0/22 | 1k | ARIN | US | 21st May 1990 |
| 140.232.76.0/23 | 512 | ARIN | US | 11th Aug 2026 |
| 140.232.78.0/23 | 512 | ARIN | US | 21st May 1990 |
| 140.232.80.0/23 | 512 | ARIN | US | 21st May 1990 |
| 140.232.84.0/22 | 1k | ARIN | US | 21st May 1990 |
| 140.232.88.0/24 | 256 | ARIN | US | 15th May 2026 |
| 140.232.89.0/24 | 256 | ARIN | US | 24th Jun 2026 |
| 140.232.91.0/24 | 256 | ARIN | US | 21st May 1990 |
| 140.232.93.0/24 | 256 | ARIN | US | 21st May 1990 |
| 140.232.94.0/23 | 512 | ARIN | US | 21st May 1990 |
| 140.232.96.0/19 | 8.2k | ARIN | US | 21st May 1990 |
| 140.235.112.0/23 | 512 | ARIN | US | 3rd Oct 2024 |
| 140.235.114.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.120.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.126.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.127.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.152.0/22 | 1k | ARIN | US | 3rd Oct 2024 |
| 140.235.184.0/24 | 256 | ARIN |  CA | 3rd Oct 2024 |
| 140.235.185.0/24 | 256 | ARIN | US | 9th Oct 2024 |
| 140.235.186.0/23 | 512 | ARIN | US | 23rd Dec 2024 |
| 140.235.238.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.244.0/22 | 1k | ARIN | US | 3rd Oct 2024 |
| 140.235.48.0/22 | 1k | ARIN | US | 4th Oct 2024 |
| 140.235.56.0/22 | 1k | ARIN | US | 3rd Oct 2024 |
| 140.235.76.0/22 | 1k | ARIN | US | 3rd Oct 2024 |
| 140.235.84.0/22 | 1k | ARIN | US | 3rd Oct 2024 |
| 140.24.0.0/16 | 65.5k | ARIN | US | 8th Apr 1990 |
| 140.26.0.0/16 | 65.5k | ARIN | US | 8th Apr 1990 |
| 140.4.0.0/16 | 65.5k | ARIN | US | 8th Apr 1990 |
| 140.76.0.0/16 | 65.5k | ARIN | US | 9th Apr 1990 |
| 140.82.64.0/19 | 8.2k | ARIN | US | 30th May 2018 |
| 140.82.96.0/20 | 4.1k | ARIN | US | 30th May 2018 |
| 140.87.0.0/16 | 65.5k | ARIN | US | 9th Apr 1990 |
| 140.88.0.0/16 | 65.5k | ARIN | US | 9th Apr 1990 |
| 141.102.0.0/16 | 65.5k | ARIN | US | 6th Jul 1990 |
| 141.109.128.0/19 | 8.2k | ARIN | CA | 12th Jul 1990 |
| 141.121.0.0/16 | 65.5k | ARIN | US | 20th Oct 1990 |
| 141.128.0.0/16 | 65.5k | ARIN | US | 20th Oct 1990 |
| 141.159.0.0/16 | 65.5k | ARIN | US | 24th Apr 1990 |
| 141.173.0.0/16 | 65.5k | ARIN | US | 24th Jan 1992 |
| 141.177.0.0/16 | 65.5k | ARIN | US | 30th Jan 1995 |
| 141.180.0.0/16 | 65.5k | ARIN | US | 26th Jul 1990 |
| 141.183.0.0/16 | 65.5k | ARIN | US | 26th Jul 1990 |
| 141.184.0.0/16 | 65.5k | ARIN | US | 26th Jul 1990 |
| 141.193.128.0/22 | 1k | ARIN | CA | 1st Apr 2024 |