IEEE Registration Authority
MAC address prefix E0:5A:9F is registered to IEEE Registration Authority in the IEEE OUI registry. Any device whose MAC address begins with E0:5A:9F has a network interface built by IEEE Registration Authority. 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 E0:5A:9F:00:00:00 to E0:5A:9F:FF:FF:FF.
- OUI prefix
- E0:5A:9F
- Hyphen form
- E0-5A-9F
- MAC range
- E0:5A:9F:00:00:00 – E0:5A:9F:FF:FF:FF
- Addresses in block
- 16,777,216
- Organization
- IEEE Registration Authority
- Address
- 445 Hoes Lane Piscataway NJ US 08554
- 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 "IEEE Registration Authority"archived source →
- 2026-07-17Assigned to "IEEE Registration Authority"
Nearby in the registry
The prefixes assigned immediately before and after E0:5A:9F:
- Emergent Vision Technologies Inc.E0:55:97
- Lootom Telcovideo Network (Wuxi) Co LtdE0:56:89
- Yunhight MicroelectronicsE0:56:94
- AxesNetwork Solutions inc.E0:56:F4
- Laerdal MedicalE0:58:9E
- Espressif Inc.E0:5A:1B
- Innovid, Co., Ltd.E0:5B:70
- Ruijie Networks Co.,LTDE0:5D:54
- Oy Everon AbE0:5D:5C
- Detlef Fink Elektronik & SoftwareentwicklungE0:5D:A6
- Apple, Inc.E0:5F:45
- Cisco Systems, IncE0:5F:B9
FAQ
- Which company owns MAC address prefix E0:5A:9F?
- MAC address prefix E0:5A:9F is registered to IEEE Registration Authority in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with E0:5A:9F has a network interface built by IEEE Registration Authority.
- What is the OUI E0:5A:9F?
- E0:5A:9F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to IEEE Registration Authority. It covers every address from E0:5A:9F:00:00:00 to E0:5A:9F:FF:FF:FF, or 16,777,216 addresses in total. It is also written E0-5A-9F.
- How do I find the manufacturer of a MAC address?
- Take the first three octets of the address — in E0:5A:9F:00:00:00 that is E0:5A:9F — 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 IEEE Registration Authority located?
- IEEE Registration Authority is listed at 445 Hoes Lane Piscataway NJ US 08554 in the IEEE OUI registry entry for E0:5A:9F. This is the address the organization registered with the IEEE, which may differ from its current operating address.