What this means
The IEEE assigned the MA-L block 3891FB to Xenox Holding BV. Every network interface they manufacture under this block has a MAC address beginning with these digits, followed by a unique per-device identifier. If a device on your network shows a MAC starting 38:91:FB, it is Xenox Holding BV hardware.
Frequently Asked Questions
Who owns MAC prefix 3891FB?
3891FB is registered to Xenox Holding BV in the IEEE MA-L registry.
What does the MA-L registry type mean?
An MA-L assignment, the IEEE's original OUI format, gives the vendor the first three octets and 16,777,216 device addresses under them. Xenox Holding BV's block covers 16,777,216 addresses.
What devices use 3891FB?
Any network device with a MAC address starting 38:91:FB was manufactured by or for Xenox Holding BV.