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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
30,476 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.4.245.0/24 | 256 | ARIN |  US | 13th Dec 1993 |
| 199.4.248.0/24 | 256 | ARIN | US | 13th Dec 1993 |
| 199.4.252.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.4.253.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.4.254.0/24 | 256 | ARIN | US | 14th Dec 1993 |
| 199.4.8.0/21 | 2k | ARIN | US | 14th Sept 1993 |
| 199.43.1.0/24 | 256 | ARIN |  CA | 5th Jan 1994 |
| 199.43.104.0/22 | 1k | ARIN | US | 2nd Feb 1994 |
| 199.43.110.0/24 | 256 | ARIN | CA | 4th Feb 1994 |
| 199.43.111.0/24 | 256 | ARIN | CA | 9th Feb 1994 |
| 199.43.112.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.43.113.0/24 | 256 | ARIN | CA | 6th Jun 1994 |
| 199.43.116.0/24 | 256 | ARIN | CA | 8th Mar 1994 |
| 199.43.117.0/24 | 256 | ARIN | CA | 11th Mar 1994 |
| 199.43.118.0/24 | 256 | ARIN | CA | 29th Mar 1994 |
| 199.43.122.0/24 | 256 | ARIN | CA | 26th Apr 1994 |
| 199.43.123.0/24 | 256 | ARIN | CA | 26th Apr 1994 |
| 199.43.124.0/22 | 1k | ARIN | CA | 26th Apr 1994 |
| 199.43.128.0/23 | 512 | ARIN | CA | 26th Apr 1994 |
| 199.43.136.0/21 | 2k | ARIN | CA | 14th Mar 1994 |
| 199.43.144.0/23 | 512 | ARIN | CA | 10th Jul 2014 |
| 199.43.147.0/24 | 256 | ARIN | CA | 14th Mar 1994 |
| 199.43.150.0/23 | 512 | ARIN | CA | 10th Mar 1994 |
| 199.43.152.0/21 | 2k | ARIN | CA | 10th Mar 1994 |
| 199.43.16.0/23 | 512 | ARIN | US | 2nd Feb 1994 |
| 199.43.160.0/21 | 2k | ARIN | CA | 10th Mar 1994 |
| 199.43.168.0/22 | 1k | ARIN | CA | 10th Mar 1994 |
| 199.43.188.0/24 | 256 | ARIN | US | 1st Mar 1994 |
| 199.43.192.0/23 | 512 | ARIN | US | 1st Mar 1994 |
| 199.43.194.0/24 | 256 | ARIN | US | 1st Mar 1994 |
| 199.43.2.0/24 | 256 | ARIN | CA | 12th Jan 1994 |
| 199.43.20.0/22 | 1k | ARIN | US | 2nd Feb 1994 |
| 199.43.208.0/20 | 4.1k | ARIN | US | 16th Dec 1993 |
| 199.43.226.0/23 | 512 | ARIN | US | 7th Dec 1993 |
| 199.43.228.0/22 | 1k | ARIN | US | 7th Dec 1993 |
| 199.43.232.0/22 | 1k | ARIN | US | 7th Dec 1993 |
| 199.43.236.0/23 | 512 | ARIN | US | 7th Dec 1993 |
| 199.43.238.0/23 | 512 | ARIN | US | 7th Dec 1993 |
| 199.43.24.0/21 | 2k | ARIN | US | 2nd Feb 1994 |
| 199.43.240.0/23 | 512 | ARIN | US | 7th Dec 1993 |
| 199.43.242.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 199.43.243.0/24 | 256 | ARIN | CA | 7th Dec 1993 |
| 199.43.244.0/23 | 512 | ARIN | CA | 7th Dec 1993 |
| 199.43.248.0/24 | 256 | ARIN | CA | 17th May 1994 |
| 199.43.3.0/24 | 256 | ARIN | CA | 1st Feb 1994 |
| 199.43.32.0/21 | 2k | ARIN | US | 2nd Feb 1994 |
| 199.43.40.0/22 | 1k | ARIN | US | 2nd Feb 1994 |
| 199.43.46.0/23 | 512 | ARIN | US | 2nd Feb 1994 |
| 199.43.62.0/24 | 256 | ARIN | US | 2nd Feb 1994 |
| 199.43.96.0/21 | 2k | ARIN | US | 2nd Feb 1994 |