Data as of Nov 3, 2026
12.253.40.0/21
No anonymizer space · no proxy exits in 30 daysAT&T WorldNet · space held by AT&T Enterprises, LLC
Announcements
Less specific
Covering announcements
| Prefix | Origin | Type | Leased from | Proxy exits | Holder | RPKI |
|---|---|---|---|---|---|---|
| 12.240.0.0/12 since Sep 2025 | AS7018 | Residential | 346 27 always on | AT&T Enterprises, LLC | ||
| 12.128.0.0/9 | AS7018 | Residential | IP broker Rackdog (part) | 5,160 278 always on | AT&T Enterprises, LLC | |
| 12.0.0.0/8 | AS7018 | Residential | 13,255 715 always on | AT&T Enterprises, LLC |
Registrations in this block
The registry's network records over this block, widest first, each under its parent.
| Range | Addresses | Netname | Holder | Type | Created | Abuse contact |
|---|---|---|---|---|---|---|
| 12.0.0.0/8 | 16,777,216 | ATT | AT&T Enterprises, LLC (AEL-360) · US | Direct Allocation | Aug 23, 1983 | [email protected] |
| └ 12.253.40.0/21 | 2,048 | ATTW-012210174023 | CFWN Pool-MP3L3BS (C02408499) | Reassigned | Jan 22, 2010 | [email protected] via ATT |
A contact marked “via” is the registry's: the record names none of its own, so the registry hands down its parent's.
Network & registry
Announced by
Covering announcement 12.253.0.0/18
- Prefix
- 12.253.0.0/18
- Announced by
- AS8030 AT&T WorldNet
- Type
- Residential
- RPKI
- RPKI valid
- Netname
- ATT
- Registrant
- AT&T Enterprises, LLC
- RIR
- ARIN
Origin network
AS8030
US
- Name
- AT&T WorldNet
- Type
- Internet provider
- Registered
- Aug 30, 1996
- Domain
- attmail.com
- Spamhaus ASN-DROP
- not listed
Routing timeline
Covering aggregate above, the prefix's own history below
12.253.0.0/18
Routing history
- Pattern
- Stable
- First seen
- Dec 2015
- Current origin since
- Dec 2015 · 11 yr
- Origin networks
- 1
RPKI
Route origin authorizations
| ROA prefix | ASN | Max len | Anchor | Verdict |
|---|---|---|---|---|
| 12.253.0.0/18 | AS8030 | /18 | ARIN | RPKI valid |
| 12.240.0.0/12 | AS7018 | /12 | ARIN | Another network |
IRR
Route objects on 12.253.0.0/18
| Origin | Registry | Description | Maintainer | Modified |
|---|---|---|---|---|
| AS8030 | ARIN | AT&T Enterprises, LLC | MNT-AEL-360 | Jun 29, 2026 |
Whois
Registration for this announcement
- Range
- 12.0.0.0/8
- Netname
- ATT
- Registrant
- AT&T Enterprises, LLC
- Organization
- AT&T Enterprises, LLC (AEL-360)
- Org address
- 208 S. Akard St., Dallas, TX, 75202
- Org country
- US
- Type
- Direct Allocation
- Handle
- NET-12-0-0-0-1
- Parent
- NET-12-0-0-0-0
- Created
- Aug 23, 1983
- RIR
- ARIN
- Country
- US
- Delegated
- Aug 23, 1983
- Status
- assigned
Report abuse
Abuse contact
- [email protected]
- Name
- abuse
- Phone
- +1-919-319-8167
- Handle
- ABUSE7-ARIN