Which company owns MAC address prefix A0:9D:91?

MAC address prefix A0:9D:91 is registered to SoundBridge in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A0:9D:91 has a network interface built by SoundBridge.

What is the OUI A0:9D:91?

A0:9D:91 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to SoundBridge. It covers every address from A0:9D:91:00:00:00 to A0:9D:91:FF:FF:FF, or 16,777,216 addresses in total. It is also written A0-9D-91.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in A0:9D:91:00:00:00 that is A0:9D:91 — and look that prefix up in the IEEE OUI registry. If the second-lowest bit of the first octet is set, the address is locally administered (a randomized or private MAC), which belongs to no manufacturer and will not resolve; modern phones and laptops use these by default on each network.

Where is SoundBridge located?

SoundBridge is listed at #810, IT Convergence Industrial Bldg. 47, Gyeongdae-ro 17-Gil, Buk-gu, Daegu KR 41566 in the IEEE OUI registry entry for A0:9D:91. This is the address the organization registered with the IEEE, which may differ from its current operating address.

SoundBridge

MAC address prefix A0:9D:91 is registered to SoundBridge in the IEEE OUI registry. Any device whose MAC address begins with A0:9D:91 has a network interface built by SoundBridge. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address — it covers every MAC from A0:9D:91:00:00:00 to A0:9D:91:FF:FF:FF.

OUI prefix: A0:9D:91
Hyphen form: A0-9D-91
MAC range: A0:9D:91:00:00:00 – A0:9D:91:FF:FF:FF
Addresses in block: 16,777,216
Organization: SoundBridge
Address: #810, IT Convergence Industrial Bldg. 47, Gyeongdae-ro 17-Gil, Buk-gu, Daegu KR 41566
Source: IEEE OUI registry

Have a full MAC address? Look it up— we'll also tell you if it's a randomized (private) address rather than a real manufacturer prefix.

Assignment history (2)

The IEEE registry publishes current state only — this is the change record we've kept since we started tracking it daily.

2016-07-29Assigned to "SoundBridge"
archived source →
2026-07-17Assigned to "SoundBridge"

Nearby in the registry

The prefixes assigned immediately before and after A0:9D:91:

FAQ

Which company owns MAC address prefix A0:9D:91?: MAC address prefix A0:9D:91 is registered to SoundBridge in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A0:9D:91 has a network interface built by SoundBridge.
What is the OUI A0:9D:91?: A0:9D:91 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to SoundBridge. It covers every address from A0:9D:91:00:00:00 to A0:9D:91:FF:FF:FF, or 16,777,216 addresses in total. It is also written A0-9D-91.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in A0:9D:91:00:00:00 that is A0:9D:91 — and look that prefix up in the IEEE OUI registry. If the second-lowest bit of the first octet is set, the address is locally administered (a randomized or private MAC), which belongs to no manufacturer and will not resolve; modern phones and laptops use these by default on each network.
Where is SoundBridge located?: SoundBridge is listed at #810, IT Convergence Industrial Bldg. 47, Gyeongdae-ro 17-Gil, Buk-gu, Daegu KR 41566 in the IEEE OUI registry entry for A0:9D:91. This is the address the organization registered with the IEEE, which may differ from its current operating address.