Which company owns MAC address prefix 44:B4:12?

MAC address prefix 44:B4:12 is registered to SIUS AG in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 44:B4:12 has a network interface built by SIUS AG.

What is the OUI 44:B4:12?

44:B4:12 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to SIUS AG. It covers every address from 44:B4:12:00:00:00 to 44:B4:12:FF:FF:FF, or 16,777,216 addresses in total. It is also written 44-B4-12.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 44:B4:12:00:00:00 that is 44:B4:12 — 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 SIUS AG located?

SIUS AG is listed at Im Langhag 1 Effretikon CH 8307 in the IEEE OUI registry entry for 44:B4:12. This is the address the organization registered with the IEEE, which may differ from its current operating address.

SIUS AG

MAC address prefix 44:B4:12 is registered to SIUS AG in the IEEE OUI registry. Any device whose MAC address begins with 44:B4:12 has a network interface built by SIUS AG. 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 44:B4:12:00:00:00 to 44:B4:12:FF:FF:FF.

OUI prefix: 44:B4:12
Hyphen form: 44-B4-12
MAC range: 44:B4:12:00:00:00 – 44:B4:12:FF:FF:FF
Addresses in block: 16,777,216
Organization: SIUS AG
Address: Im Langhag 1 Effretikon CH 8307
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.

2017-09-08Assigned to "SIUS AG"
archived source →
2026-07-17Assigned to "SIUS AG"

Nearby in the registry

The prefixes assigned immediately before and after 44:B4:12:

FAQ

Which company owns MAC address prefix 44:B4:12?: MAC address prefix 44:B4:12 is registered to SIUS AG in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 44:B4:12 has a network interface built by SIUS AG.
What is the OUI 44:B4:12?: 44:B4:12 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to SIUS AG. It covers every address from 44:B4:12:00:00:00 to 44:B4:12:FF:FF:FF, or 16,777,216 addresses in total. It is also written 44-B4-12.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 44:B4:12:00:00:00 that is 44:B4:12 — 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 SIUS AG located?: SIUS AG is listed at Im Langhag 1 Effretikon CH 8307 in the IEEE OUI registry entry for 44:B4:12. This is the address the organization registered with the IEEE, which may differ from its current operating address.