I have no idea if it is an OEM wing, i was led to believe that when i bought the car a few years ago, that it was a special edition GTS-T (from the factory), and with it came
Carbon fibre gear knob / handbrake
Body kit (with a GTR rear wing)
and a GTR Active LSD
However i don't have any tangible evidence that this is the case. I don't know how to check whether it is genuine or not... to be honest i dont care, its a wing that does very little but please some people aesthetically. Its got all the stuff in the right places as per genuine units...