Which company owns MAC address prefix B4:89:10?

MAC address prefix B4:89:10 is registered to Coster T.E. S.P.A. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B4:89:10 has a network interface built by Coster T.E. S.P.A..

What is the OUI B4:89:10?

B4:89:10 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Coster T.E. S.P.A.. It covers every address from B4:89:10:00:00:00 to B4:89:10:FF:FF:FF, or 16,777,216 addresses in total. It is also written B4-89-10.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in B4:89:10:00:00:00 that is B4:89:10 — 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 Coster T.E. S.P.A. located?

Coster T.E. S.P.A. is listed at Via San Giovanni Battista De La Salle 4/a Milano MI IT 20132 in the IEEE OUI registry entry for B4:89:10. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Coster T.E. S.P.A.

MAC address prefix B4:89:10 is registered to Coster T.E. S.P.A. in the IEEE OUI registry. Any device whose MAC address begins with B4:89:10 has a network interface built by Coster T.E. S.P.A.. 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 B4:89:10:00:00:00 to B4:89:10:FF:FF:FF.

OUI prefix: B4:89:10
Hyphen form: B4-89-10
MAC range: B4:89:10:00:00:00 – B4:89:10:FF:FF:FF
Addresses in block: 16,777,216
Organization: Coster T.E. S.P.A.
Address: Via San Giovanni Battista De La Salle 4/a Milano MI IT 20132
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 "Coster T.E. S.P.A."
archived source →
2026-07-17Assigned to "Coster T.E. S.P.A."

Nearby in the registry

The prefixes assigned immediately before and after B4:89:10:

FAQ

Which company owns MAC address prefix B4:89:10?: MAC address prefix B4:89:10 is registered to Coster T.E. S.P.A. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B4:89:10 has a network interface built by Coster T.E. S.P.A..
What is the OUI B4:89:10?: B4:89:10 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Coster T.E. S.P.A.. It covers every address from B4:89:10:00:00:00 to B4:89:10:FF:FF:FF, or 16,777,216 addresses in total. It is also written B4-89-10.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in B4:89:10:00:00:00 that is B4:89:10 — 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 Coster T.E. S.P.A. located?: Coster T.E. S.P.A. is listed at Via San Giovanni Battista De La Salle 4/a Milano MI IT 20132 in the IEEE OUI registry entry for B4:89:10. This is the address the organization registered with the IEEE, which may differ from its current operating address.