Which company owns MAC address prefix B0:38:6C?

MAC address prefix B0:38:6C is registered to EFM Networks in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B0:38:6C has a network interface built by EFM Networks.

What is the OUI B0:38:6C?

B0:38:6C is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to EFM Networks. It covers every address from B0:38:6C:00:00:00 to B0:38:6C:FF:FF:FF, or 16,777,216 addresses in total. It is also written B0-38-6C.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in B0:38:6C:00:00:00 that is B0:38:6C — 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 EFM Networks located?

EFM Networks is listed at 6th Floor, Benposra II B/D 15, Jukjeon-ro, Giheung-gu Yongin-si Kyunggi-do KR 16897 in the IEEE OUI registry entry for B0:38:6C. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does EFM Networks own?

EFM Networks holds 8 OUI prefixes in the IEEE registry, of which B0:38:6C is one. A device made by EFM Networks could carry a MAC address from any of them.

EFM Networks

MAC address prefix B0:38:6C is registered to EFM Networks in the IEEE OUI registry. Any device whose MAC address begins with B0:38:6C has a network interface built by EFM Networks. 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 B0:38:6C:00:00:00 to B0:38:6C:FF:FF:FF.

OUI prefix: B0:38:6C
Hyphen form: B0-38-6C
MAC range: B0:38:6C:00:00:00 – B0:38:6C:FF:FF:FF
Addresses in block: 16,777,216
Organization: EFM Networks
Address: 6th Floor, Benposra II B/D 15, Jukjeon-ro, Giheung-gu Yongin-si Kyunggi-do KR 16897
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.

Other prefixes from EFM Networks

EFM Networks holds 8 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

Assignment history (2)

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

2024-04-16Assigned to "EFM Networks"
archived source →
2026-07-17Assigned to "EFM Networks"

Nearby in the registry

The prefixes assigned immediately before and after B0:38:6C:

FAQ

Which company owns MAC address prefix B0:38:6C?: MAC address prefix B0:38:6C is registered to EFM Networks in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B0:38:6C has a network interface built by EFM Networks.
What is the OUI B0:38:6C?: B0:38:6C is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to EFM Networks. It covers every address from B0:38:6C:00:00:00 to B0:38:6C:FF:FF:FF, or 16,777,216 addresses in total. It is also written B0-38-6C.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in B0:38:6C:00:00:00 that is B0:38:6C — 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 EFM Networks located?: EFM Networks is listed at 6th Floor, Benposra II B/D 15, Jukjeon-ro, Giheung-gu Yongin-si Kyunggi-do KR 16897 in the IEEE OUI registry entry for B0:38:6C. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does EFM Networks own?: EFM Networks holds 8 OUI prefixes in the IEEE registry, of which B0:38:6C is one. A device made by EFM Networks could carry a MAC address from any of them.