Which company owns MAC address prefix B0:E3:9D?

MAC address prefix B0:E3:9D is registered to CAT SYSTEM CO.,LTD. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B0:E3:9D has a network interface built by CAT SYSTEM CO.,LTD..

What is the OUI B0:E3:9D?

B0:E3:9D is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to CAT SYSTEM CO.,LTD.. It covers every address from B0:E3:9D:00:00:00 to B0:E3:9D:FF:FF:FF, or 16,777,216 addresses in total. It is also written B0-E3-9D.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in B0:E3:9D:00:00:00 that is B0:E3:9D — 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 CAT SYSTEM CO.,LTD. located?

CAT SYSTEM CO.,LTD. is listed at 3-147-27 Higasi-sinmachi Hirohata-ku Himeji Hyogo JP 671-1121 in the IEEE OUI registry entry for B0:E3:9D. This is the address the organization registered with the IEEE, which may differ from its current operating address.

CAT SYSTEM CO.,LTD.

MAC address prefix B0:E3:9D is registered to CAT SYSTEM CO.,LTD. in the IEEE OUI registry. Any device whose MAC address begins with B0:E3:9D has a network interface built by CAT SYSTEM 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 B0:E3:9D:00:00:00 to B0:E3:9D:FF:FF:FF.

OUI prefix: B0:E3:9D
Hyphen form: B0-E3-9D
MAC range: B0:E3:9D:00:00:00 – B0:E3:9D:FF:FF:FF
Addresses in block: 16,777,216
Organization: CAT SYSTEM CO.,LTD.
Address: 3-147-27 Higasi-sinmachi Hirohata-ku Himeji Hyogo JP 671-1121
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 "CAT SYSTEM CO.,LTD."
archived source →
2026-07-17Assigned to "CAT SYSTEM CO.,LTD."

Nearby in the registry

The prefixes assigned immediately before and after B0:E3:9D:

FAQ

Which company owns MAC address prefix B0:E3:9D?: MAC address prefix B0:E3:9D is registered to CAT SYSTEM CO.,LTD. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B0:E3:9D has a network interface built by CAT SYSTEM CO.,LTD..
What is the OUI B0:E3:9D?: B0:E3:9D is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to CAT SYSTEM CO.,LTD.. It covers every address from B0:E3:9D:00:00:00 to B0:E3:9D:FF:FF:FF, or 16,777,216 addresses in total. It is also written B0-E3-9D.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in B0:E3:9D:00:00:00 that is B0:E3:9D — 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 CAT SYSTEM CO.,LTD. located?: CAT SYSTEM CO.,LTD. is listed at 3-147-27 Higasi-sinmachi Hirohata-ku Himeji Hyogo JP 671-1121 in the IEEE OUI registry entry for B0:E3:9D. This is the address the organization registered with the IEEE, which may differ from its current operating address.