Which company owns MAC address prefix A4:4A:D3?

MAC address prefix A4:4A:D3 is registered to ST Electronics(Shanghai) Co.,Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A4:4A:D3 has a network interface built by ST Electronics(Shanghai) Co.,Ltd.

What is the OUI A4:4A:D3?

A4:4A:D3 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to ST Electronics(Shanghai) Co.,Ltd. It covers every address from A4:4A:D3:00:00:00 to A4:4A:D3:FF:FF:FF, or 16,777,216 addresses in total. It is also written A4-4A-D3.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in A4:4A:D3:00:00:00 that is A4:4A:D3 — 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 ST Electronics(Shanghai) Co.,Ltd located?

ST Electronics(Shanghai) Co.,Ltd is listed at Floors 1&3, No.6 Building, No.1151 Lianxi Road Shanghai Shanghai CN 201204 in the IEEE OUI registry entry for A4:4A:D3. This is the address the organization registered with the IEEE, which may differ from its current operating address.

ST Electronics(Shanghai) Co.,Ltd

MAC address prefix A4:4A:D3 is registered to ST Electronics(Shanghai) Co.,Ltd in the IEEE OUI registry. Any device whose MAC address begins with A4:4A:D3 has a network interface built by ST Electronics(Shanghai) Co.,Ltd. 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 A4:4A:D3:00:00:00 to A4:4A:D3:FF:FF:FF.

OUI prefix: A4:4A:D3
Hyphen form: A4-4A-D3
MAC range: A4:4A:D3:00:00:00 – A4:4A:D3:FF:FF:FF
Addresses in block: 16,777,216
Organization: ST Electronics(Shanghai) Co.,Ltd
Address: Floors 1&3, No.6 Building, No.1151 Lianxi Road Shanghai Shanghai CN 201204
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 "ST Electronics(Shanghai) Co.,Ltd"
archived source →
2026-07-17Assigned to "ST Electronics(Shanghai) Co.,Ltd"

Nearby in the registry

The prefixes assigned immediately before and after A4:4A:D3:

FAQ

Which company owns MAC address prefix A4:4A:D3?: MAC address prefix A4:4A:D3 is registered to ST Electronics(Shanghai) Co.,Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A4:4A:D3 has a network interface built by ST Electronics(Shanghai) Co.,Ltd.
What is the OUI A4:4A:D3?: A4:4A:D3 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to ST Electronics(Shanghai) Co.,Ltd. It covers every address from A4:4A:D3:00:00:00 to A4:4A:D3:FF:FF:FF, or 16,777,216 addresses in total. It is also written A4-4A-D3.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in A4:4A:D3:00:00:00 that is A4:4A:D3 — 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 ST Electronics(Shanghai) Co.,Ltd located?: ST Electronics(Shanghai) Co.,Ltd is listed at Floors 1&3, No.6 Building, No.1151 Lianxi Road Shanghai Shanghai CN 201204 in the IEEE OUI registry entry for A4:4A:D3. This is the address the organization registered with the IEEE, which may differ from its current operating address.