Which company owns MAC address prefix C4:EE:F5?

MAC address prefix C4:EE:F5 is registered to II-VI Incorporated in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C4:EE:F5 has a network interface built by II-VI Incorporated.

What is the OUI C4:EE:F5?

C4:EE:F5 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to II-VI Incorporated. It covers every address from C4:EE:F5:00:00:00 to C4:EE:F5:FF:FF:FF, or 16,777,216 addresses in total. It is also written C4-EE-F5.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in C4:EE:F5:00:00:00 that is C4:EE:F5 — 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 II-VI Incorporated located?

II-VI Incorporated is listed at Network Solutions,343 Daniel Zenker Dr., Suite 102 Horseheads NY US 14845 in the IEEE OUI registry entry for C4:EE:F5. This is the address the organization registered with the IEEE, which may differ from its current operating address.

II-VI Incorporated

MAC address prefix C4:EE:F5 is registered to II-VI Incorporated in the IEEE OUI registry. Any device whose MAC address begins with C4:EE:F5 has a network interface built by II-VI Incorporated. 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 C4:EE:F5:00:00:00 to C4:EE:F5:FF:FF:FF.

OUI prefix: C4:EE:F5
Hyphen form: C4-EE-F5
MAC range: C4:EE:F5:00:00:00 – C4:EE:F5:FF:FF:FF
Addresses in block: 16,777,216
Organization: II-VI Incorporated
Address: Network Solutions,343 Daniel Zenker Dr., Suite 102 Horseheads NY US 14845
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 (3)

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 "Oclaro, Inc."
archived source →
2017-09-08Renamed from "Oclaro, Inc." to "II-VI Incorporated"
archived source →
2026-07-17Assigned to "II-VI Incorporated"

Nearby in the registry

The prefixes assigned immediately before and after C4:EE:F5:

FAQ

Which company owns MAC address prefix C4:EE:F5?: MAC address prefix C4:EE:F5 is registered to II-VI Incorporated in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C4:EE:F5 has a network interface built by II-VI Incorporated.
What is the OUI C4:EE:F5?: C4:EE:F5 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to II-VI Incorporated. It covers every address from C4:EE:F5:00:00:00 to C4:EE:F5:FF:FF:FF, or 16,777,216 addresses in total. It is also written C4-EE-F5.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in C4:EE:F5:00:00:00 that is C4:EE:F5 — 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 II-VI Incorporated located?: II-VI Incorporated is listed at Network Solutions,343 Daniel Zenker Dr., Suite 102 Horseheads NY US 14845 in the IEEE OUI registry entry for C4:EE:F5. This is the address the organization registered with the IEEE, which may differ from its current operating address.