Which company owns MAC address prefix 5C:BF:03?

MAC address prefix 5C:BF:03 is registered to EMOCO in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 5C:BF:03 has a network interface built by EMOCO.

What is the OUI 5C:BF:03?

5C:BF:03 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to EMOCO. It covers every address from 5C:BF:03:00:00:00 to 5C:BF:03:FF:FF:FF, or 16,777,216 addresses in total. It is also written 5C-BF-03.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 5C:BF:03:00:00:00 that is 5C:BF:03 — 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 EMOCO located?

EMOCO is listed at Valhallavägen 5 Lidingö SE 18151 in the IEEE OUI registry entry for 5C:BF:03. This is the address the organization registered with the IEEE, which may differ from its current operating address.

EMOCO

MAC address prefix 5C:BF:03 is registered to EMOCO in the IEEE OUI registry. Any device whose MAC address begins with 5C:BF:03 has a network interface built by EMOCO. 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 5C:BF:03:00:00:00 to 5C:BF:03:FF:FF:FF.

OUI prefix: 5C:BF:03
Hyphen form: 5C-BF-03
MAC range: 5C:BF:03:00:00:00 – 5C:BF:03:FF:FF:FF
Addresses in block: 16,777,216
Organization: EMOCO
Address: Valhallavägen 5 Lidingö SE 18151
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.

2026-01-08Assigned to "EMOCO"
archived source →
2026-07-17Assigned to "EMOCO"

Nearby in the registry

The prefixes assigned immediately before and after 5C:BF:03:

FAQ

Which company owns MAC address prefix 5C:BF:03?: MAC address prefix 5C:BF:03 is registered to EMOCO in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 5C:BF:03 has a network interface built by EMOCO.
What is the OUI 5C:BF:03?: 5C:BF:03 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to EMOCO. It covers every address from 5C:BF:03:00:00:00 to 5C:BF:03:FF:FF:FF, or 16,777,216 addresses in total. It is also written 5C-BF-03.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 5C:BF:03:00:00:00 that is 5C:BF:03 — 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 EMOCO located?: EMOCO is listed at Valhallavägen 5 Lidingö SE 18151 in the IEEE OUI registry entry for 5C:BF:03. This is the address the organization registered with the IEEE, which may differ from its current operating address.