Which company owns MAC address prefix C4:3A:9F?

MAC address prefix C4:3A:9F is registered to Siconix Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C4:3A:9F has a network interface built by Siconix Inc..

What is the OUI C4:3A:9F?

C4:3A:9F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Siconix Inc.. It covers every address from C4:3A:9F:00:00:00 to C4:3A:9F:FF:FF:FF, or 16,777,216 addresses in total. It is also written C4-3A-9F.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in C4:3A:9F:00:00:00 that is C4:3A:9F — 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 Siconix Inc. located?

Siconix Inc. is listed at #28, 2333 18th Ave NE Calgary Alberta CA T2E 8T6 in the IEEE OUI registry entry for C4:3A:9F. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Siconix Inc.

MAC address prefix C4:3A:9F is registered to Siconix Inc. in the IEEE OUI registry. Any device whose MAC address begins with C4:3A:9F has a network interface built by Siconix Inc.. 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 C4:3A:9F:00:00:00 to C4:3A:9F:FF:FF:FF.

OUI prefix: C4:3A:9F
Hyphen form: C4-3A-9F
MAC range: C4:3A:9F:00:00:00 – C4:3A:9F:FF:FF:FF
Addresses in block: 16,777,216
Organization: Siconix Inc.
Address: #28, 2333 18th Ave NE Calgary Alberta CA T2E 8T6
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 "Siconix Inc."
archived source →
2026-07-17Assigned to "Siconix Inc."

Nearby in the registry

The prefixes assigned immediately before and after C4:3A:9F:

FAQ

Which company owns MAC address prefix C4:3A:9F?: MAC address prefix C4:3A:9F is registered to Siconix Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C4:3A:9F has a network interface built by Siconix Inc..
What is the OUI C4:3A:9F?: C4:3A:9F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Siconix Inc.. It covers every address from C4:3A:9F:00:00:00 to C4:3A:9F:FF:FF:FF, or 16,777,216 addresses in total. It is also written C4-3A-9F.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in C4:3A:9F:00:00:00 that is C4:3A:9F — 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 Siconix Inc. located?: Siconix Inc. is listed at #28, 2333 18th Ave NE Calgary Alberta CA T2E 8T6 in the IEEE OUI registry entry for C4:3A:9F. This is the address the organization registered with the IEEE, which may differ from its current operating address.