Advanced Digital Broadcast, Ltd. (Taiwan) — 00:03:91 (MA-L)

A MAC address beginning 00:03:91 belongs to Advanced Digital Broadcast, Ltd., the Taiwan-registered arm of the Advanced Digital Broadcast (ADB) corporate group, and most likely appears on set-top box, DVR, or broadband/residential-gateway hardware — the product line the ADB group is documented to build, though that link is inferred from the group rather than confirmed for this specific prefix.

This registration is a separate legal entity from the already-DONE vendor entry vendor-adb, which covers "Advanced Digital Broadcast SA" (Switzerland) and its three MA-L blocks (68:63:59, C4:77:AF, 20:83:F8). This Taiwan Ltd. registration is a fourth, distinct MA-L block, apparently the Taiwan operations arm of the same ADB corporate family rather than a duplicate of the Swiss blocks.

The wider ADB group has a documented corporate history: founded 1995, R&D centered in Poland, corporate headquarters and operations established in Taipei, Taiwan from 1997, a Swiss stock-exchange IPO in 2005, and a take-private in 2015. That history and the Taipei address on this specific registration corroborate that the Ltd. entity is a real operating arm, not a shell filing.

No CVE or security-advisory record turned up for this prefix in this pass, and no device-specific citation ties 00:03:91 itself to a particular product — the device-class attribution above rests on the ADB group's known product line, not on a source naming this exact block.

IEEE assignment

00:03:91 → "Advanced Digital Broadcast, Ltd.", registered Taipei, Taiwan, R.O.C. [Confirmed] — the IEEE MA-L registry

Registry / block size

MA-L (24-bit OUI); single block (~16.8M addresses) [Confirmed] — IEEE the IEEE MA-L registry

HQ / country

8F, 145 Chung Shan N. Rd. Sec. 2, Taipei, Taiwan, R.O.C. [Confirmed] — the IEEE MA-L registry, hwaddress.com

Company status

ADB corporate group — founded 1995, R&D in Poland, Taipei HQ/operations from 1997, Swiss exchange IPO 2005, went private 2015 [Likely] — https://en.wikipedia.org/wiki/Advanced_Digital_Broadcast

Device types

set-top boxes, DVRs, residential/broadband gateways (group-level product line; not confirmed specifically for this prefix) [Likely] — https://en.wikipedia.org/wiki/Advanced_Digital_Broadcast

Notable products

operator set-top boxes, DVRs, broadband/residential gateways (ADB group, not prefix-specific) [Likely] — https://en.wikipedia.org/wiki/Advanced_Digital_Broadcast

Related vendors

vendor-adb (Advanced Digital Broadcast SA, Switzerland; DONE; 68:63:59, C4:77:AF, 20:83:F8) — same corporate family, separate legal entity [Confirmed] — /mac/vendor/adb/

Date registered

Not available — IEEE publishes no MAC assignment dates for OUI blocks; maclookup.app's "First Registration: 24 October 2001" is a third-party database artifact, not an IEEE fact [Confirmed] — https://maclookup.app/vendors/advanced-digital-broadcast-ltd

Security context

No CVE/advisory record found in this pass; search was inconclusive rather than a confirmed negative [Unknown] — https://nvd.nist.gov/vuln/search

Analyst note

A 00:03:91 MAC identifies genuine ADB Ltd. (Taiwan) hardware; treat the device-class attribution as inferred from the wider ADB group's product line rather than confirmed for this exact prefix, and don't conflate this entity with the separately-DONE Swiss vendor-adb entry.