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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 in United States
26,315 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.88.172.0/22 | 1k | ARIN |  US | 15th Feb 1994 |
| 199.88.176.0/24 | 256 | ARIN | US | 15th Feb 1994 |
| 199.88.177.0/24 | 256 | ARIN | US | 15th Feb 1994 |
| 199.88.178.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.180.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.181.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.182.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.183.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.185.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.186.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.188.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.189.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.190.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.192.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.193.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.195.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.196.0/24 | 256 | ARIN | US | 16th Feb 1994 |
| 199.88.197.0/24 | 256 | ARIN | US | 17th Feb 1994 |
| 199.88.199.0/24 | 256 | ARIN | US | 17th Feb 1994 |
| 199.88.200.0/24 | 256 | ARIN | US | 17th Feb 1994 |
| 199.88.201.0/24 | 256 | ARIN | US | 17th Feb 1994 |
| 199.88.202.0/24 | 256 | ARIN | US | 17th Feb 1994 |
| 199.88.203.0/24 | 256 | ARIN | US | 17th Feb 1994 |
| 199.88.204.0/24 | 256 | ARIN | US | 17th Feb 1994 |
| 199.88.207.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.88.216.0/21 | 2k | ARIN | US | 16th Feb 1994 |
| 199.88.224.0/21 | 2k | ARIN | US | 16th Feb 1994 |
| 199.88.232.0/22 | 1k | ARIN | US | 17th Feb 1994 |
| 199.88.236.0/22 | 1k | ARIN | US | 17th Feb 1994 |
| 199.88.244.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.88.248.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.88.249.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.88.251.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.88.254.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.89.129.0/24 | 256 | ARIN | US | 18th Sept 2015 |
| 199.89.131.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.89.135.0/24 | 256 | ARIN | US | 22nd Feb 1994 |
| 199.89.138.0/24 | 256 | ARIN | US | 22nd Feb 1994 |
| 199.89.140.0/24 | 256 | ARIN | US | 22nd Feb 1994 |
| 199.89.144.0/24 | 256 | ARIN | US | 22nd Feb 1994 |
| 199.89.148.0/24 | 256 | ARIN | US | 23rd Feb 1994 |
| 199.89.150.0/24 | 256 | ARIN | US | 23rd Feb 1994 |
| 199.89.151.0/24 | 256 | ARIN | US | 23rd Feb 1994 |
| 199.89.152.0/24 | 256 | ARIN | US | 23rd Feb 1994 |
| 199.89.153.0/24 | 256 | ARIN | US | 23rd Feb 1994 |
| 199.89.154.0/23 | 512 | ARIN | US | 23rd Feb 1994 |
| 199.89.156.0/24 | 256 | ARIN | US | 23rd Feb 1994 |
| 199.89.16.0/20 | 4.1k | ARIN | US | 14th Dec 1993 |
| 199.89.163.0/24 | 256 | ARIN | US | 23rd Feb 1994 |
| 199.89.171.0/24 | 256 | ARIN | US | 23rd Feb 1994 |