Which company owns MAC address prefix 20:FA:BB?

MAC address prefix 20:FA:BB is registered to Cambridge Executive Limited in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 20:FA:BB has a network interface built by Cambridge Executive Limited.

What is the OUI 20:FA:BB?

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

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 20:FA:BB:00:00:00 that is 20:FA:BB — 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 Cambridge Executive Limited located?

Cambridge Executive Limited is listed at St John's Innovation Centre Cambridge Cambridgeshire GB CB40WS in the IEEE OUI registry entry for 20:FA:BB. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Cambridge Executive Limited

MAC address prefix 20:FA:BB is registered to Cambridge Executive Limited in the IEEE OUI registry. Any device whose MAC address begins with 20:FA:BB has a network interface built by Cambridge Executive Limited. 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:FA:BB:00:00:00 to 20:FA:BB:FF:FF:FF.

OUI prefix: 20:FA:BB
Hyphen form: 20-FA-BB
MAC range: 20:FA:BB:00:00:00 – 20:FA:BB:FF:FF:FF
Addresses in block: 16,777,216
Organization: Cambridge Executive Limited
Address: St John's Innovation Centre Cambridge Cambridgeshire GB CB40WS
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 "Cambridge Executive Limited"
archived source →
2026-07-17Assigned to "Cambridge Executive Limited"

Nearby in the registry

The prefixes assigned immediately before and after 20:FA:BB:

FAQ

Which company owns MAC address prefix 20:FA:BB?: MAC address prefix 20:FA:BB is registered to Cambridge Executive Limited in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 20:FA:BB has a network interface built by Cambridge Executive Limited.
What is the OUI 20:FA:BB?: 20:FA:BB is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Cambridge Executive Limited. It covers every address from 20:FA:BB:00:00:00 to 20:FA:BB:FF:FF:FF, or 16,777,216 addresses in total. It is also written 20-FA-BB.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 20:FA:BB:00:00:00 that is 20:FA:BB — 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 Cambridge Executive Limited located?: Cambridge Executive Limited is listed at St John's Innovation Centre Cambridge Cambridgeshire GB CB40WS in the IEEE OUI registry entry for 20:FA:BB. This is the address the organization registered with the IEEE, which may differ from its current operating address.