Which company owns MAC address prefix 8C:39:5C?

MAC address prefix 8C:39:5C is registered to Bit4id Srl in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 8C:39:5C has a network interface built by Bit4id Srl.

What is the OUI 8C:39:5C?

8C:39:5C is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Bit4id Srl. It covers every address from 8C:39:5C:00:00:00 to 8C:39:5C:FF:FF:FF, or 16,777,216 addresses in total. It is also written 8C-39-5C.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 8C:39:5C:00:00:00 that is 8C:39:5C — 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 Bit4id Srl located?

Bit4id Srl is listed at Via Diocleziano, 107 Naples IT 80125 in the IEEE OUI registry entry for 8C:39:5C. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Bit4id Srl

MAC address prefix 8C:39:5C is registered to Bit4id Srl in the IEEE OUI registry. Any device whose MAC address begins with 8C:39:5C has a network interface built by Bit4id Srl. 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 8C:39:5C:00:00:00 to 8C:39:5C:FF:FF:FF.

OUI prefix: 8C:39:5C
Hyphen form: 8C-39-5C
MAC range: 8C:39:5C:00:00:00 – 8C:39:5C:FF:FF:FF
Addresses in block: 16,777,216
Organization: Bit4id Srl
Address: Via Diocleziano, 107 Naples IT 80125
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 "Bit4id Srl"
archived source →
2026-07-17Assigned to "Bit4id Srl"

Nearby in the registry

The prefixes assigned immediately before and after 8C:39:5C:

FAQ

Which company owns MAC address prefix 8C:39:5C?: MAC address prefix 8C:39:5C is registered to Bit4id Srl in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 8C:39:5C has a network interface built by Bit4id Srl.
What is the OUI 8C:39:5C?: 8C:39:5C is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Bit4id Srl. It covers every address from 8C:39:5C:00:00:00 to 8C:39:5C:FF:FF:FF, or 16,777,216 addresses in total. It is also written 8C-39-5C.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 8C:39:5C:00:00:00 that is 8C:39:5C — 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 Bit4id Srl located?: Bit4id Srl is listed at Via Diocleziano, 107 Naples IT 80125 in the IEEE OUI registry entry for 8C:39:5C. This is the address the organization registered with the IEEE, which may differ from its current operating address.