Which company owns MAC address prefix 1C:57:3E?

MAC address prefix 1C:57:3E is registered to Altice Labs in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 1C:57:3E has a network interface built by Altice Labs.

What is the OUI 1C:57:3E?

1C:57:3E is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Altice Labs. It covers every address from 1C:57:3E:00:00:00 to 1C:57:3E:FF:FF:FF, or 16,777,216 addresses in total. It is also written 1C-57-3E.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 1C:57:3E:00:00:00 that is 1C:57:3E — 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 Altice Labs located?

Altice Labs is listed at NIF 504705610, Rua Eng. José Ferreira Pinto Basto Aveiro PT 3810-106 in the IEEE OUI registry entry for 1C:57:3E. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does Altice Labs own?

Altice Labs holds 5 OUI prefixes in the IEEE registry, of which 1C:57:3E is one. A device made by Altice Labs could carry a MAC address from any of them.

Altice Labs

MAC address prefix 1C:57:3E is registered to Altice Labs in the IEEE OUI registry. Any device whose MAC address begins with 1C:57:3E has a network interface built by Altice Labs. 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 1C:57:3E:00:00:00 to 1C:57:3E:FF:FF:FF.

OUI prefix: 1C:57:3E
Hyphen form: 1C-57-3E
MAC range: 1C:57:3E:00:00:00 – 1C:57:3E:FF:FF:FF
Addresses in block: 16,777,216
Organization: Altice Labs
Address: NIF 504705610, Rua Eng. José Ferreira Pinto Basto Aveiro PT 3810-106
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 Altice Labs

Altice Labs holds 5 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

Assignment history (3)

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

2021-06-10Assigned to "Altice Labs S.A."
archived source →
2024-11-20Renamed from "Altice Labs S.A." to "Altice Labs"
archived source →
2026-07-17Assigned to "Altice Labs"

Nearby in the registry

The prefixes assigned immediately before and after 1C:57:3E:

FAQ

Which company owns MAC address prefix 1C:57:3E?: MAC address prefix 1C:57:3E is registered to Altice Labs in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 1C:57:3E has a network interface built by Altice Labs.
What is the OUI 1C:57:3E?: 1C:57:3E is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Altice Labs. It covers every address from 1C:57:3E:00:00:00 to 1C:57:3E:FF:FF:FF, or 16,777,216 addresses in total. It is also written 1C-57-3E.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 1C:57:3E:00:00:00 that is 1C:57:3E — 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 Altice Labs located?: Altice Labs is listed at NIF 504705610, Rua Eng. José Ferreira Pinto Basto Aveiro PT 3810-106 in the IEEE OUI registry entry for 1C:57:3E. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does Altice Labs own?: Altice Labs holds 5 OUI prefixes in the IEEE registry, of which 1C:57:3E is one. A device made by Altice Labs could carry a MAC address from any of them.