Which company owns MAC address prefix 00:09:3E?

MAC address prefix 00:09:3E is registered to C&I Technologies in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 00:09:3E has a network interface built by C&I Technologies.

What is the OUI 00:09:3E?

00:09:3E is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to C&I Technologies. It covers every address from 00:09:3E:00:00:00 to 00:09:3E:FF:FF:FF, or 16,777,216 addresses in total. It is also written 00-09-3E.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 00:09:3E:00:00:00 that is 00:09:3E — 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 C&I Technologies located?

C&I Technologies is listed at #303 Kwanbo Plaza B/D, 1467-2 Anyang-Shi Kyunggi-Do KR 431-808 in the IEEE OUI registry entry for 00:09:3E. This is the address the organization registered with the IEEE, which may differ from its current operating address.

C&I Technologies

MAC address prefix 00:09:3E is registered to C&I Technologies in the IEEE OUI registry. Any device whose MAC address begins with 00:09:3E has a network interface built by C&I Technologies. 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 00:09:3E:00:00:00 to 00:09:3E:FF:FF:FF.

OUI prefix: 00:09:3E
Hyphen form: 00-09-3E
MAC range: 00:09:3E:00:00:00 – 00:09:3E:FF:FF:FF
Addresses in block: 16,777,216
Organization: C&I Technologies
Address: #303 Kwanbo Plaza B/D, 1467-2 Anyang-Shi Kyunggi-Do KR 431-808
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 "C&I Technologies"
archived source →
2026-07-17Assigned to "C&I Technologies"

Nearby in the registry

The prefixes assigned immediately before and after 00:09:3E:

FAQ

Which company owns MAC address prefix 00:09:3E?: MAC address prefix 00:09:3E is registered to C&I Technologies in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 00:09:3E has a network interface built by C&I Technologies.
What is the OUI 00:09:3E?: 00:09:3E is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to C&I Technologies. It covers every address from 00:09:3E:00:00:00 to 00:09:3E:FF:FF:FF, or 16,777,216 addresses in total. It is also written 00-09-3E.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 00:09:3E:00:00:00 that is 00:09:3E — 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 C&I Technologies located?: C&I Technologies is listed at #303 Kwanbo Plaza B/D, 1467-2 Anyang-Shi Kyunggi-Do KR 431-808 in the IEEE OUI registry entry for 00:09:3E. This is the address the organization registered with the IEEE, which may differ from its current operating address.