Not OEM. Some people get an M3 bumper then they see something like the Hamman lip kit which is only compatable with a stock bumper and then want it so they switch.
My 328i has an M3 bumper. I used to have Velocity Splitters on it as well but since i lowered it the splitters kept scrapping so i took em off.
heres what it looks like on my car (with the splitters):