Which company owns MAC address prefix 00:0A:CA?

MAC address prefix 00:0A:CA is registered to YOKOYAMA SHOKAI CO.,Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 00:0A:CA has a network interface built by YOKOYAMA SHOKAI CO.,Ltd..

What is the OUI 00:0A:CA?

00:0A:CA is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to YOKOYAMA SHOKAI CO.,Ltd.. It covers every address from 00:0A:CA:00:00:00 to 00:0A:CA:FF:FF:FF, or 16,777,216 addresses in total. It is also written 00-0A-CA.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 00:0A:CA:00:00:00 that is 00:0A:CA — 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 YOKOYAMA SHOKAI CO.,Ltd. located?

YOKOYAMA SHOKAI CO.,Ltd. is listed at 6-96 Matsumura Kanazawa Ishikawa JP 920-0348 in the IEEE OUI registry entry for 00:0A:CA. This is the address the organization registered with the IEEE, which may differ from its current operating address.

YOKOYAMA SHOKAI CO.,Ltd.

MAC address prefix 00:0A:CA is registered to YOKOYAMA SHOKAI CO.,Ltd. in the IEEE OUI registry. Any device whose MAC address begins with 00:0A:CA has a network interface built by YOKOYAMA SHOKAI CO.,Ltd.. 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 00:0A:CA:00:00:00 to 00:0A:CA:FF:FF:FF.

OUI prefix: 00:0A:CA
Hyphen form: 00-0A-CA
MAC range: 00:0A:CA:00:00:00 – 00:0A:CA:FF:FF:FF
Addresses in block: 16,777,216
Organization: YOKOYAMA SHOKAI CO.,Ltd.
Address: 6-96 Matsumura Kanazawa Ishikawa JP 920-0348
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 "YOKOYAMA SHOKAI CO.,Ltd."
archived source →
2026-07-17Assigned to "YOKOYAMA SHOKAI CO.,Ltd."

Nearby in the registry

The prefixes assigned immediately before and after 00:0A:CA:

FAQ

Which company owns MAC address prefix 00:0A:CA?: MAC address prefix 00:0A:CA is registered to YOKOYAMA SHOKAI CO.,Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 00:0A:CA has a network interface built by YOKOYAMA SHOKAI CO.,Ltd..
What is the OUI 00:0A:CA?: 00:0A:CA is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to YOKOYAMA SHOKAI CO.,Ltd.. It covers every address from 00:0A:CA:00:00:00 to 00:0A:CA:FF:FF:FF, or 16,777,216 addresses in total. It is also written 00-0A-CA.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 00:0A:CA:00:00:00 that is 00:0A:CA — 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 YOKOYAMA SHOKAI CO.,Ltd. located?: YOKOYAMA SHOKAI CO.,Ltd. is listed at 6-96 Matsumura Kanazawa Ishikawa JP 920-0348 in the IEEE OUI registry entry for 00:0A:CA. This is the address the organization registered with the IEEE, which may differ from its current operating address.