Which company owns MAC address prefix 3C:CF:B4?

MAC address prefix 3C:CF:B4 is registered to Telink Semiconductor (Shanghai) Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 3C:CF:B4 has a network interface built by Telink Semiconductor (Shanghai) Co., Ltd..

What is the OUI 3C:CF:B4?

3C:CF:B4 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Telink Semiconductor (Shanghai) Co., Ltd.. It covers every address from 3C:CF:B4:00:00:00 to 3C:CF:B4:FF:FF:FF, or 16,777,216 addresses in total. It is also written 3C-CF-B4.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 3C:CF:B4:00:00:00 that is 3C:CF:B4 — 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 Telink Semiconductor (Shanghai) Co., Ltd. located?

Telink Semiconductor (Shanghai) Co., Ltd. is listed at No. 1500 Zuchongzhi Rd, Building #3 Shanghai CN 201203 in the IEEE OUI registry entry for 3C:CF:B4. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does Telink Semiconductor (Shanghai) Co., Ltd. own?

Telink Semiconductor (Shanghai) Co., Ltd. holds 8 OUI prefixes in the IEEE registry, of which 3C:CF:B4 is one. A device made by Telink Semiconductor (Shanghai) Co., Ltd. could carry a MAC address from any of them.

Telink Semiconductor (Shanghai) Co., Ltd.

MAC address prefix 3C:CF:B4 is registered to Telink Semiconductor (Shanghai) Co., Ltd. in the IEEE OUI registry. Any device whose MAC address begins with 3C:CF:B4 has a network interface built by Telink Semiconductor (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 3C:CF:B4:00:00:00 to 3C:CF:B4:FF:FF:FF.

OUI prefix: 3C:CF:B4
Hyphen form: 3C-CF-B4
MAC range: 3C:CF:B4:00:00:00 – 3C:CF:B4:FF:FF:FF
Addresses in block: 16,777,216
Organization: Telink Semiconductor (Shanghai) Co., Ltd.
Address: No. 1500 Zuchongzhi Rd, Building #3 Shanghai CN 201203
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 Telink Semiconductor (Shanghai) Co., Ltd.

Telink Semiconductor (Shanghai) Co., Ltd. holds 8 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

Assignment history (2)

The IEEE registry publishes current state only — this is the change record we've kept since we started tracking it daily.

2022-07-11Assigned to "Telink Semiconductor (Shanghai) Co., Ltd."
archived source →
2026-07-17Assigned to "Telink Semiconductor (Shanghai) Co., Ltd."

Nearby in the registry

The prefixes assigned immediately before and after 3C:CF:B4:

FAQ

Which company owns MAC address prefix 3C:CF:B4?: MAC address prefix 3C:CF:B4 is registered to Telink Semiconductor (Shanghai) Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 3C:CF:B4 has a network interface built by Telink Semiconductor (Shanghai) Co., Ltd..
What is the OUI 3C:CF:B4?: 3C:CF:B4 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Telink Semiconductor (Shanghai) Co., Ltd.. It covers every address from 3C:CF:B4:00:00:00 to 3C:CF:B4:FF:FF:FF, or 16,777,216 addresses in total. It is also written 3C-CF-B4.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 3C:CF:B4:00:00:00 that is 3C:CF:B4 — 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 Telink Semiconductor (Shanghai) Co., Ltd. located?: Telink Semiconductor (Shanghai) Co., Ltd. is listed at No. 1500 Zuchongzhi Rd, Building #3 Shanghai CN 201203 in the IEEE OUI registry entry for 3C:CF:B4. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does Telink Semiconductor (Shanghai) Co., Ltd. own?: Telink Semiconductor (Shanghai) Co., Ltd. holds 8 OUI prefixes in the IEEE registry, of which 3C:CF:B4 is one. A device made by Telink Semiconductor (Shanghai) Co., Ltd. could carry a MAC address from any of them.