82599 Phantom MAC address

[gregsachs]

Ok, I'm confused by an "extra" MAC showing up on an intel IOM 82599 Dual port card ( AXX10GBNIAIOM ).
From the switch,
MAC-Address Port Type Index VLAN
001e.67b5.c5d2 1/2/1 Dynamic 22200 1
001e.67b5.c5d0 1/2/1 Dynamic 36384 1
D0 is the MAC that is shown in windows device manager.
D1 is Port #2 on the card, which I am not using. So where is the D2 MAC coming from? The H-V virtual switch has the same MAC as the NIC port, D0.
So why does the icx6450 show this extra MAC?

 

[altmind]

could it be some intel v-pro/LOM on a shared network port?

 

[gregsachs]

could it be some intel v-pro/LOM on a shared network port?

I can't find any information/way of accessing/documentation if it is. The BMC does not show that MAC as a NIC.
The 82599 data sheet only shows 2 MAC blocks.