Which company owns MAC address prefix EC:4C:4D?

MAC address prefix EC:4C:4D is registered to ZAO NPK RoTeK in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with EC:4C:4D has a network interface built by ZAO NPK RoTeK.

What is the OUI EC:4C:4D?

EC:4C:4D is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to ZAO NPK RoTeK. It covers every address from EC:4C:4D:00:00:00 to EC:4C:4D:FF:FF:FF, or 16,777,216 addresses in total. It is also written EC-4C-4D.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in EC:4C:4D:00:00:00 that is EC:4C:4D — 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 ZAO NPK RoTeK located?

ZAO NPK RoTeK is listed at Bild. 119-1, Prospekt Mira Moscow Moscow RU 129223 in the IEEE OUI registry entry for EC:4C:4D. This is the address the organization registered with the IEEE, which may differ from its current operating address.

ZAO NPK RoTeK

MAC address prefix EC:4C:4D is registered to ZAO NPK RoTeK in the IEEE OUI registry. Any device whose MAC address begins with EC:4C:4D has a network interface built by ZAO NPK RoTeK. 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 EC:4C:4D:00:00:00 to EC:4C:4D:FF:FF:FF.

OUI prefix: EC:4C:4D
Hyphen form: EC-4C-4D
MAC range: EC:4C:4D:00:00:00 – EC:4C:4D:FF:FF:FF
Addresses in block: 16,777,216
Organization: ZAO NPK RoTeK
Address: Bild. 119-1, Prospekt Mira Moscow Moscow RU 129223
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.

2016-07-29Assigned to "ZAO NPK RoTeK"
archived source →
2026-07-17Assigned to "ZAO NPK RoTeK"

Nearby in the registry

The prefixes assigned immediately before and after EC:4C:4D:

FAQ

Which company owns MAC address prefix EC:4C:4D?: MAC address prefix EC:4C:4D is registered to ZAO NPK RoTeK in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with EC:4C:4D has a network interface built by ZAO NPK RoTeK.
What is the OUI EC:4C:4D?: EC:4C:4D is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to ZAO NPK RoTeK. It covers every address from EC:4C:4D:00:00:00 to EC:4C:4D:FF:FF:FF, or 16,777,216 addresses in total. It is also written EC-4C-4D.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in EC:4C:4D:00:00:00 that is EC:4C:4D — 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 ZAO NPK RoTeK located?: ZAO NPK RoTeK is listed at Bild. 119-1, Prospekt Mira Moscow Moscow RU 129223 in the IEEE OUI registry entry for EC:4C:4D. This is the address the organization registered with the IEEE, which may differ from its current operating address.