Which company owns MAC address prefix 74:99:75?

MAC address prefix 74:99:75 is registered to IBM Corporation in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 74:99:75 has a network interface built by IBM Corporation.

What is the OUI 74:99:75?

74:99:75 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to IBM Corporation. It covers every address from 74:99:75:00:00:00 to 74:99:75:FF:FF:FF, or 16,777,216 addresses in total. It is also written 74-99-75.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 74:99:75:00:00:00 that is 74:99:75 — 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 IBM Corporation located?

IBM Corporation is listed at 4400 North First Street San Jose CA US 95134 in the IEEE OUI registry entry for 74:99:75. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does IBM Corporation own?

IBM Corporation holds 2 OUI prefixes in the IEEE registry, of which 74:99:75 is one. A device made by IBM Corporation could carry a MAC address from any of them.

IBM Corporation

MAC address prefix 74:99:75 is registered to IBM Corporation in the IEEE OUI registry. Any device whose MAC address begins with 74:99:75 has a network interface built by IBM Corporation. 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 74:99:75:00:00:00 to 74:99:75:FF:FF:FF.

OUI prefix: 74:99:75
Hyphen form: 74-99-75
MAC range: 74:99:75:00:00:00 – 74:99:75:FF:FF:FF
Addresses in block: 16,777,216
Organization: IBM Corporation
Address: 4400 North First Street San Jose CA US 95134
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 IBM Corporation

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

6C:AE:8B

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 "IBM Corporation"
archived source →
2026-07-17Assigned to "IBM Corporation"

Nearby in the registry

The prefixes assigned immediately before and after 74:99:75:

FAQ

Which company owns MAC address prefix 74:99:75?: MAC address prefix 74:99:75 is registered to IBM Corporation in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 74:99:75 has a network interface built by IBM Corporation.
What is the OUI 74:99:75?: 74:99:75 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to IBM Corporation. It covers every address from 74:99:75:00:00:00 to 74:99:75:FF:FF:FF, or 16,777,216 addresses in total. It is also written 74-99-75.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 74:99:75:00:00:00 that is 74:99:75 — 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 IBM Corporation located?: IBM Corporation is listed at 4400 North First Street San Jose CA US 95134 in the IEEE OUI registry entry for 74:99:75. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does IBM Corporation own?: IBM Corporation holds 2 OUI prefixes in the IEEE registry, of which 74:99:75 is one. A device made by IBM Corporation could carry a MAC address from any of them.