Private
MAC address prefix 58:09:43 is registered to Private in the IEEE OUI registry. Any device whose MAC address begins with 58:09:43 has a network interface built by Private. 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 58:09:43:00:00:00 to 58:09:43:FF:FF:FF.
- OUI prefix
- 58:09:43
- Hyphen form
- 58-09-43
- MAC range
- 58:09:43:00:00:00 – 58:09:43:FF:FF:FF
- Addresses in block
- 16,777,216
- Organization
- Private
- 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 "Private"archived source →
- 2026-07-17Assigned to "Private"
Nearby in the registry
The prefixes assigned immediately before and after 58:09:43:
- Tianjin Huisun Technology Co.,Ltd.58:04:CB
- LABRIS NETWORKS58:05:28
- Elettronica GF S.r.L.58:05:56
- Seiko Epson Corporation58:05:D9
- Nokia Solutions and Networks GmbH & Co. KG58:07:F8
- Fiber Optic & telecommunication INC.58:08:FA
- Amazon Technologies Inc.58:09:87
- Kivic Inc.58:09:E5
- Cisco Systems, Inc58:0A:20
- Apple, Inc.58:0A:D4
- GREE ELECTRIC APPLIANCES, INC. OF ZHUHAI58:0D:0D
- Sagemcom Broadband SAS58:0E:85
FAQ
- Which company owns MAC address prefix 58:09:43?
- MAC address prefix 58:09:43 is registered to Private in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 58:09:43 has a network interface built by Private.
- What is the OUI 58:09:43?
- 58:09:43 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Private. It covers every address from 58:09:43:00:00:00 to 58:09:43:FF:FF:FF, or 16,777,216 addresses in total. It is also written 58-09-43.
- How do I find the manufacturer of a MAC address?
- Take the first three octets of the address — in 58:09:43:00:00:00 that is 58:09:43 — 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.