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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
30,427 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 138.39.0.0/16 | 65.5k | ARIN |  US | 31st Jan 1990 |
| 138.42.0.0/16 | 65.5k | ARIN | US | 31st Jan 1990 |
| 138.53.0.0/16 | 65.5k | ARIN | US | 7th Feb 1990 |
| 138.54.0.0/15 | 131k | ARIN | US | 7th Feb 1990 |
| 138.76.0.0/16 | 65.5k | ARIN | US | 2nd Mar 1990 |
| 138.82.0.0/16 | 65.5k | ARIN |  CA | 9th Mar 1990 |
| 138.84.200.0/24 | 256 | ARIN | US | 9th Mar 1990 |
| 138.84.202.0/24 | 256 | ARIN | US | 9th Mar 1990 |
| 138.93.0.0/16 | 65.5k | ARIN | US | 19th Apr 1990 |
| 138.95.0.0/16 | 65.5k | ARIN | US | 20th Apr 1990 |
| 139.136.0.0/16 | 65.5k | ARIN | US | 14th Mar 1990 |
| 139.172.0.0/16 | 65.5k | ARIN | US | 25th Mar 1990 |
| 139.177.112.0/24 | 256 | ARIN | US | 3rd Jun 2020 |
| 139.177.113.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 139.177.114.0/23 | 512 | ARIN | US | 26th Mar 1990 |
| 139.177.116.0/22 | 1k | ARIN | US | 26th Mar 1990 |
| 139.177.208.0/20 | 4.1k | ARIN | US | 26th Mar 1990 |
| 139.180.18.0/23 | 512 | ARIN | US | 19th Dec 2018 |
| 139.187.0.0/16 | 65.5k | ARIN | US | 29th Mar 1990 |
| 139.46.0.0/16 | 65.5k | ARIN | US | 18th Jun 1990 |
| 139.49.0.0/16 | 65.5k | ARIN | US | 20th Jun 1990 |
| 139.56.0.0/16 | 65.5k | ARIN | US | 1st Jun 2020 |
| 139.60.212.0/22 | 1k | ARIN | US | 10th Oct 2017 |
| 139.60.227.0/24 | 256 | ARIN | US | 20th Dec 2017 |
| 139.60.240.0/20 | 4.1k | ARIN | US | 7th Nov 2017 |
| 139.60.36.0/22 | 1k | ARIN | US | 9th Dec 2016 |
| 139.64.202.0/24 | 256 | ARIN | US | 8th Apr 2022 |
| 139.64.206.0/24 | 256 | ARIN | US | 29th Jun 2020 |
| 139.64.244.0/22 | 1k | ARIN | CA | 1st Jul 2020 |
| 139.65.0.0/16 | 65.5k | ARIN | US | 4th Jul 1990 |
| 139.68.128.0/18 | 16.4k | ARIN | US | 7th Feb 1990 |
| 139.69.0.0/16 | 65.5k | ARIN | US | 7th Feb 1990 |
| 139.77.0.0/16 | 65.5k | ARIN | US | 9th Feb 1990 |
| 139.93.0.0/16 | 65.5k | ARIN | US | 27th Jul 2026 |
| 140.169.0.0/16 | 65.5k | ARIN | US | 8th May 1990 |
| 140.170.0.0/16 | 65.5k | ARIN | US | 8th May 1990 |
| 140.173.0.0/16 | 65.5k | ARIN | US | 16th May 1990 |
| 140.176.0.0/16 | 65.5k | ARIN | US | 16th May 1990 |
| 140.190.112.0/21 | 2k | ARIN | US | 23rd Nov 2022 |
| 140.190.128.0/18 | 16.4k | ARIN | US | 23rd Nov 2022 |
| 140.190.192.0/19 | 8.2k | ARIN | US | 23rd Nov 2022 |
| 140.190.224.0/20 | 4.1k | ARIN | US | 23rd Nov 2022 |
| 140.190.240.0/21 | 2k | ARIN | US | 23rd Nov 2022 |
| 140.190.64.0/19 | 8.2k | ARIN | US | 23rd Nov 2022 |
| 140.190.96.0/20 | 4.1k | ARIN | US | 23rd Nov 2022 |
| 140.208.224.0/20 | 4.1k | ARIN | US | 11th Jun 1990 |
| 140.222.0.0/16 | 65.5k | ARIN | US | 15th Jun 1990 |
| 140.225.96.0/19 | 8.2k | ARIN | US | 15th Jun 1990 |
| 140.232.128.0/19 | 8.2k | ARIN | US | 21st May 1990 |
| 140.232.160.0/22 | 1k | ARIN | US | 21st May 2026 |