Which company owns MAC address prefix 3C:99:8C?

MAC address prefix 3C:99:8C is registered to Houwa System Design Corp. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 3C:99:8C has a network interface built by Houwa System Design Corp..

What is the OUI 3C:99:8C?

3C:99:8C is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Houwa System Design Corp.. It covers every address from 3C:99:8C:00:00:00 to 3C:99:8C:FF:FF:FF, or 16,777,216 addresses in total. It is also written 3C-99-8C.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 3C:99:8C:00:00:00 that is 3C:99:8C — 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 Houwa System Design Corp. located?

Houwa System Design Corp. is listed at 4F Matubara Building 3-22-14 Shibuyaku Higashi Tokyo JP 150-0011 in the IEEE OUI registry entry for 3C:99:8C. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Houwa System Design Corp.

MAC address prefix 3C:99:8C is registered to Houwa System Design Corp. in the IEEE OUI registry. Any device whose MAC address begins with 3C:99:8C has a network interface built by Houwa System Design Corp.. 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 3C:99:8C:00:00:00 to 3C:99:8C:FF:FF:FF.

OUI prefix: 3C:99:8C
Hyphen form: 3C-99-8C
MAC range: 3C:99:8C:00:00:00 – 3C:99:8C:FF:FF:FF
Addresses in block: 16,777,216
Organization: Houwa System Design Corp.
Address: 4F Matubara Building 3-22-14 Shibuyaku Higashi Tokyo JP 150-0011
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.

2023-07-11Assigned to "Houwa System Design Corp."
archived source →
2026-07-17Assigned to "Houwa System Design Corp."

Nearby in the registry

The prefixes assigned immediately before and after 3C:99:8C:

FAQ

Which company owns MAC address prefix 3C:99:8C?: MAC address prefix 3C:99:8C is registered to Houwa System Design Corp. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 3C:99:8C has a network interface built by Houwa System Design Corp..
What is the OUI 3C:99:8C?: 3C:99:8C is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Houwa System Design Corp.. It covers every address from 3C:99:8C:00:00:00 to 3C:99:8C:FF:FF:FF, or 16,777,216 addresses in total. It is also written 3C-99-8C.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 3C:99:8C:00:00:00 that is 3C:99:8C — 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 Houwa System Design Corp. located?: Houwa System Design Corp. is listed at 4F Matubara Building 3-22-14 Shibuyaku Higashi Tokyo JP 150-0011 in the IEEE OUI registry entry for 3C:99:8C. This is the address the organization registered with the IEEE, which may differ from its current operating address.