Which company owns MAC address prefix 20:3A:EF?

MAC address prefix 20:3A:EF is registered to Sivantos GmbH in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 20:3A:EF has a network interface built by Sivantos GmbH.

What is the OUI 20:3A:EF?

20:3A:EF is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Sivantos GmbH. It covers every address from 20:3A:EF:00:00:00 to 20:3A:EF:FF:FF:FF, or 16,777,216 addresses in total. It is also written 20-3A-EF.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 20:3A:EF:00:00:00 that is 20:3A: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 Sivantos GmbH located?

Sivantos GmbH is listed at Henri-Dunant-Strasse 100 Erlangen Bavaria DE 91058 in the IEEE OUI registry entry for 20:3A:EF. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does Sivantos GmbH own?

Sivantos GmbH holds 2 OUI prefixes in the IEEE registry, of which 20:3A:EF is one. A device made by Sivantos GmbH could carry a MAC address from any of them.

Sivantos GmbH

MAC address prefix 20:3A:EF is registered to Sivantos GmbH in the IEEE OUI registry. Any device whose MAC address begins with 20:3A:EF has a network interface built by Sivantos GmbH. 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 20:3A:EF:00:00:00 to 20:3A:EF:FF:FF:FF.

OUI prefix: 20:3A:EF
Hyphen form: 20-3A-EF
MAC range: 20:3A:EF:00:00:00 – 20:3A:EF:FF:FF:FF
Addresses in block: 16,777,216
Organization: Sivantos GmbH
Address: Henri-Dunant-Strasse 100 Erlangen Bavaria DE 91058
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 Sivantos GmbH

Sivantos GmbH holds 2 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

D4:87:CC

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 "Sivantos GmbH"
archived source →
2026-07-17Assigned to "Sivantos GmbH"

Nearby in the registry

The prefixes assigned immediately before and after 20:3A:EF:

FAQ

Which company owns MAC address prefix 20:3A:EF?: MAC address prefix 20:3A:EF is registered to Sivantos GmbH in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 20:3A:EF has a network interface built by Sivantos GmbH.
What is the OUI 20:3A:EF?: 20:3A:EF is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Sivantos GmbH. It covers every address from 20:3A:EF:00:00:00 to 20:3A:EF:FF:FF:FF, or 16,777,216 addresses in total. It is also written 20-3A-EF.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 20:3A:EF:00:00:00 that is 20:3A: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 Sivantos GmbH located?: Sivantos GmbH is listed at Henri-Dunant-Strasse 100 Erlangen Bavaria DE 91058 in the IEEE OUI registry entry for 20:3A:EF. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does Sivantos GmbH own?: Sivantos GmbH holds 2 OUI prefixes in the IEEE registry, of which 20:3A:EF is one. A device made by Sivantos GmbH could carry a MAC address from any of them.