Which company owns MAC address prefix B4:81:BF?

MAC address prefix B4:81:BF is registered to Meta-Networks, LLC in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B4:81:BF has a network interface built by Meta-Networks, LLC.

What is the OUI B4:81:BF?

B4:81:BF is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Meta-Networks, LLC. It covers every address from B4:81:BF:00:00:00 to B4:81:BF:FF:FF:FF, or 16,777,216 addresses in total. It is also written B4-81-BF.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in B4:81:BF:00:00:00 that is B4:81:BF — 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 Meta-Networks, LLC located?

Meta-Networks, LLC is listed at Office 106C, 5/2, Varshavskaya street Saint-Petersburg Saint-Petersburg RU 196128 in the IEEE OUI registry entry for B4:81:BF. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Meta-Networks, LLC

MAC address prefix B4:81:BF is registered to Meta-Networks, LLC in the IEEE OUI registry. Any device whose MAC address begins with B4:81:BF has a network interface built by Meta-Networks, LLC. 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 B4:81:BF:00:00:00 to B4:81:BF:FF:FF:FF.

OUI prefix: B4:81:BF
Hyphen form: B4-81-BF
MAC range: B4:81:BF:00:00:00 – B4:81:BF:FF:FF:FF
Addresses in block: 16,777,216
Organization: Meta-Networks, LLC
Address: Office 106C, 5/2, Varshavskaya street Saint-Petersburg Saint-Petersburg RU 196128
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.

2018-12-21Assigned to "Meta-Networks, LLC"
archived source →
2026-07-17Assigned to "Meta-Networks, LLC"

Nearby in the registry

The prefixes assigned immediately before and after B4:81:BF:

FAQ

Which company owns MAC address prefix B4:81:BF?: MAC address prefix B4:81:BF is registered to Meta-Networks, LLC in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B4:81:BF has a network interface built by Meta-Networks, LLC.
What is the OUI B4:81:BF?: B4:81:BF is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Meta-Networks, LLC. It covers every address from B4:81:BF:00:00:00 to B4:81:BF:FF:FF:FF, or 16,777,216 addresses in total. It is also written B4-81-BF.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in B4:81:BF:00:00:00 that is B4:81:BF — 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 Meta-Networks, LLC located?: Meta-Networks, LLC is listed at Office 106C, 5/2, Varshavskaya street Saint-Petersburg Saint-Petersburg RU 196128 in the IEEE OUI registry entry for B4:81:BF. This is the address the organization registered with the IEEE, which may differ from its current operating address.