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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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.
Browse by registry
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Countries with unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,479 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.99.240.0/24 | 256 | ARIN |  US | 29th Apr 1993 |
| 198.99.242.0/24 | 256 | ARIN | US | 29th Apr 1993 |
| 198.99.243.0/24 | 256 | ARIN | US | 29th Apr 1993 |
| 198.99.245.0/24 | 256 | ARIN | US | 3rd May 1993 |
| 198.99.26.0/23 | 512 | ARIN | US | 12th Mar 2014 |
| 198.99.4.0/24 | 256 | ARIN | US | 17th Mar 1993 |
| 198.99.5.0/24 | 256 | ARIN | US | 17th Mar 1993 |
| 198.99.6.0/24 | 256 | ARIN | US | 17th Mar 1993 |
| 198.99.64.0/24 | 256 | ARIN | US | 22nd Mar 1993 |
| 198.99.66.0/24 | 256 | ARIN | US | 22nd Mar 1993 |
| 198.99.69.0/24 | 256 | ARIN | US | 23rd Mar 1993 |
| 198.99.7.0/24 | 256 | ARIN | US | 17th Mar 1993 |
| 198.99.70.0/23 | 512 | ARIN | US | 23rd Mar 1993 |
| 198.99.72.0/24 | 256 | ARIN | US | 23rd Mar 1993 |
| 198.99.73.0/24 | 256 | ARIN | US | 26th Mar 1993 |
| 198.99.74.0/24 | 256 | ARIN | US | 2nd Jul 2026 |
| 198.99.77.0/24 | 256 | ARIN | US | 26th Mar 1993 |
| 198.99.78.0/24 | 256 | ARIN | US | 26th Mar 1993 |
| 198.99.79.0/24 | 256 | ARIN | US | 26th Mar 1993 |
| 198.99.85.0/24 | 256 | ARIN | US | 27th Mar 1993 |
| 198.99.86.0/24 | 256 | ARIN | US | 27th Mar 1993 |
| 198.99.87.0/24 | 256 | ARIN | US | 27th Mar 1993 |
| 198.99.93.0/24 | 256 | ARIN | US | 30th Mar 1993 |
| 198.99.94.0/24 | 256 | ARIN | US | 31st Mar 1993 |
| 198.99.95.0/24 | 256 | ARIN | US | 31st Mar 1993 |
| 198.99.97.0/24 | 256 | ARIN | US | 31st Mar 1993 |
| 198.99.98.0/24 | 256 | ARIN | US | 31st Mar 1993 |
| 198.99.99.0/24 | 256 | ARIN | US | 31st Mar 1993 |
| 199.10.106.0/24 | 256 | ARIN | US | 30th Nov 1993 |
| 199.10.112.0/24 | 256 | ARIN | US | 3rd Dec 1993 |
| 199.10.113.0/24 | 256 | ARIN | US | 3rd Dec 1993 |
| 199.10.120.0/24 | 256 | ARIN | US | 30th Nov 1993 |
| 199.10.121.0/24 | 256 | ARIN | US | 1st Jan 1990 |
| 199.10.122.0/24 | 256 | ARIN | US | 1st Jan 1990 |
| 199.10.125.0/24 | 256 | ARIN | US | 25th Jan 1994 |
| 199.10.126.0/24 | 256 | ARIN | US | 3rd Jan 1994 |
| 199.10.136.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.10.137.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.10.140.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.10.145.0/24 | 256 | ARIN | US | 25th Jan 1994 |
| 199.10.146.0/24 | 256 | ARIN | US | 7th Mar 1994 |
| 199.10.147.0/24 | 256 | ARIN | US | 7th Mar 1994 |
| 199.10.150.0/23 | 512 | ARIN | US | 9th Feb 1994 |
| 199.10.152.0/24 | 256 | ARIN | US | 9th Feb 1994 |
| 199.10.153.0/24 | 256 | ARIN | US | 9th Feb 1994 |
| 199.10.154.0/24 | 256 | ARIN | US | 9th Feb 1994 |
| 199.10.155.0/24 | 256 | ARIN | US | 10th Feb 1994 |
| 199.10.156.0/24 | 256 | ARIN | US | 9th Feb 1994 |
| 199.10.162.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.10.180.0/24 | 256 | ARIN | US | 28th Aug 2015 |