Which company owns MAC address prefix D0:40:EF?

MAC address prefix D0:40:EF is registered to Murata Manufacturing Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with D0:40:EF has a network interface built by Murata Manufacturing Co., Ltd..

What is the OUI D0:40:EF?

D0:40:EF is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Murata Manufacturing Co., Ltd.. It covers every address from D0:40:EF:00:00:00 to D0:40:EF:FF:FF:FF, or 16,777,216 addresses in total. It is also written D0-40-EF.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in D0:40:EF:00:00:00 that is D0:40:EF — 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 Murata Manufacturing Co., Ltd. located?

Murata Manufacturing Co., Ltd. is listed at 1-10-1, Higashikotari Nagaokakyo-shi Kyoto JP 617-8555 in the IEEE OUI registry entry for D0:40:EF. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does Murata Manufacturing Co., Ltd. own?

Murata Manufacturing Co., Ltd. holds 76 OUI prefixes in the IEEE registry, of which D0:40:EF is one. A device made by Murata Manufacturing Co., Ltd. could carry a MAC address from any of them.

Murata Manufacturing Co., Ltd.

MAC address prefix D0:40:EF is registered to Murata Manufacturing Co., Ltd. in the IEEE OUI registry. Any device whose MAC address begins with D0:40:EF has a network interface built by Murata Manufacturing 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 D0:40:EF:00:00:00 to D0:40:EF:FF:FF:FF.

OUI prefix: D0:40:EF
Hyphen form: D0-40-EF
MAC range: D0:40:EF:00:00:00 – D0:40:EF:FF:FF:FF
Addresses in block: 16,777,216
Organization: Murata Manufacturing Co., Ltd.
Address: 1-10-1, Higashikotari Nagaokakyo-shi Kyoto JP 617-8555
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.

Other prefixes from Murata Manufacturing Co., Ltd.

Murata Manufacturing Co., Ltd. holds 76 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

Assignment history (2)

The IEEE registry publishes current state only — this is the change record we've kept since we started tracking it daily.

2020-11-28Assigned to "Murata Manufacturing Co., Ltd."
archived source →
2026-07-17Assigned to "Murata Manufacturing Co., Ltd."

Nearby in the registry

The prefixes assigned immediately before and after D0:40:EF:

FAQ

Which company owns MAC address prefix D0:40:EF?: MAC address prefix D0:40:EF is registered to Murata Manufacturing Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with D0:40:EF has a network interface built by Murata Manufacturing Co., Ltd..
What is the OUI D0:40:EF?: D0:40:EF is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Murata Manufacturing Co., Ltd.. It covers every address from D0:40:EF:00:00:00 to D0:40:EF:FF:FF:FF, or 16,777,216 addresses in total. It is also written D0-40-EF.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in D0:40:EF:00:00:00 that is D0:40:EF — 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 Murata Manufacturing Co., Ltd. located?: Murata Manufacturing Co., Ltd. is listed at 1-10-1, Higashikotari Nagaokakyo-shi Kyoto JP 617-8555 in the IEEE OUI registry entry for D0:40:EF. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does Murata Manufacturing Co., Ltd. own?: Murata Manufacturing Co., Ltd. holds 76 OUI prefixes in the IEEE registry, of which D0:40:EF is one. A device made by Murata Manufacturing Co., Ltd. could carry a MAC address from any of them.