Hi. Just going to change oil on my 2012 1.3 multijet. Manual says 5w/30 C2

I had intended to use GM dexos 2 oil 5w/30 But it is to C3 spec. I'm a little puzzled as as far as I know my van is the same as vauxhall combo 1.3 cdti, and Dexos 2 is specified for the combo. Is it just a matter of manufacturers recommending their own oil?