AT&T — 6 registry blocks (5 MA-L + 1 MA-M)

A MAC address beginning with one of AT&T's IEEE-registered prefixes belongs to AT&T Inc. (NYSE: T), the U.S. telecommunications carrier. AT&T holds six confirmed registry blocks under the exact organization name "AT&T" — five MA-L (24-bit) OUI blocks plus one MA-M (28-bit) block — and these addresses typically appear on AT&T-provisioned residential and business network gateways, including U-verse and Fixed Wireless Internet equipment.

Four of the five MA-L blocks (00:07:1C, 80:00:10, 08:00:6A, 00:60:D3) share a single registry address at 3300 E Renner Road, Richardson, TX. The fifth MA-L block, 80:3A:59, registers to 1025 Lenox Park Blvd, Atlanta, GA. The MA-M block, D0:93:95:2, registers to 200 South Laurel Avenue, Middletown, NJ.

Two of the prefixes — 00:07:1C and 00:60:D3 — were independently confirmed against a second lookup source beyond the IEEE registry itself. The remaining MA-L blocks (08:00:6A, 80:00:10, 80:3A:59) are listed consistently across two third-party aggregators but were not cross-checked against a third independent source in this pass. Those same aggregators also list the bare base D0:93:95, which is not an AT&T assignment: that /24 is held by the IEEE Registration Authority and sub-allocated to many unrelated registrants, and AT&T's confirmed holding beneath it is the MA-M slice D0:93:95:2 recorded above.

AT&T documents MAC-based Wi-Fi filtering and WAN MAC lookup for its provisioned gateways at a general level, without a public per-prefix-to-model mapping. Separately, CVE-2017-14115 and related CVEs disclosed hard-coded SSH credentials on Arris NVG589/NVG599 gateways deployed under AT&T U-verse — though that hardware is Arris-manufactured OEM CPE, not confirmed to run specifically on AT&T's own OUI blocks.

A distinct registry entry, 00:06:DD, belongs to "AT & T Laboratories - Cambridge Ltd" in England — the former AT&T Cambridge research lab, a separate legal entity from the AT&T Inc. blocks above — and is deliberately excluded from this vendor record.

IEEE assignment

6 registry blocks (5 MA-L + 1 MA-M) under the exact org name "AT&T" [Confirmed] — the IEEE MA-L registry, the IEEE MA-M registry

Registry / block sizes

5× MA-L (24-bit OUI): 80:3A:59, 00:07:1C, 80:00:10, 08:00:6A, 00:60:D3; 1× MA-M (28-bit OUI-28): D0:93:95:2 [Confirmed] — the IEEE MA-L registry (rows 2082, 9606, 10340, 30260, 34137), the IEEE MA-M registry (row 3954)

MA-S / OUI-36

none found under the exact org name "AT&T" [Confirmed] — the IEEE MA-S registry

Registered addresses

3300 E Renner Road, Richardson, TX 75082 (4 of 5 MA-L prefixes); 1025 Lenox Park Blvd, Atlanta, GA 30319 (80:3A:59); 200 South Laurel Avenue, Middletown, NJ 07748 (MA-M block) [Confirmed] — the IEEE MA-L registry, the IEEE MA-M registry

Company status

active, NYSE: T [Confirmed] — https://maclookup.app/vendors/at-t, https://www.netify.ai/resources/macs/brands/at-and-t

Device types

AT&T-provisioned residential/business gateways, U-verse, Fixed Wireless Internet CPE [Likely — general-level documentation only, no per-prefix model mapping] — https://www.att.com/support/article/u-verse-high-speed-internet/KM1067868/, https://www.att.com/support/article/u-verse-high-speed-internet/KM1217373/

Independently re-verified prefixes

00:07:1C, 00:60:D3 [Confirmed] — https://api.macvendors.com/00:07:1C, https://api.macvendors.com/00:60:D3

Aggregator-only prefixes (not cross-checked to a third independent source)

08:00:6A, 80:00:10, 80:3A:59 [Likely] — https://maclookup.app/vendors/at-t, https://www.netify.ai/resources/macs/brands/at-and-t

Aggregator listing of the bare base D0

93:95: both aggregators show it under AT&T, but that base is held by the IEEE Registration Authority and sub-allocated as MA-M slices to many unrelated registrants — AT&T's assignment beneath it is D0:93:95:2, so the bare base is not an AT&T prefix and is excluded from the aggregator-only list

[Confirmed] — the IEEE MA-M registry (row 3954), https://maclookup.app/vendors/at-t

Possible additional CID assignment (DA

2B:DD): named by two aggregators; not located in this project's registry files during this pass [Likely / unconfirmed against primary registry] — https://maclookup.app/vendors/at-t, https://www.netify.ai/resources/macs/brands/at-and-t

Security context

CVE-2017-14115 and related CVEs — hard-coded SSH credentials and hidden HTTP maintenance service on Arris NVG589/NVG599 gateways deployed under AT&T U-verse, ~235,000 hosts estimated exposed at disclosure [Confirmed — vulnerability; attribution to AT&T's own OUI blocks specifically is Unknown] — https://www.securityweek.com/serious-vulnerabilities-disclosed-modems-used-atts-u-verse-service/, https://www.bankinfosecurity.com/arris-made-att-routers-be-easily-compromised-a-10255, https://www.cvedetails.com/cve/CVE-2017-14115/

Data-quality trap

00:06:DD → "AT & T Laboratories - Cambridge Ltd" (England), a distinct legal entity from AT&T Inc., excluded from this record [Confirmed] — the IEEE MA-L registry (row 29425), the Wireshark manufacturer database (row 1771)

Registration dates

Unknown / not applicable — IEEE's public OUI/MA-M data publishes no assignment or registration date column; third-party "date registered" values shown by aggregators are database artifacts, not IEEE facts [Confirmed as a sourced non-fact] — the IEEE MA-L registry, the IEEE MA-M registry

IANA Reference

not applicable — OUI/MAC vendor registry entries do not carry an IANA Reference field [Confirmed — blank]