There's no filter for variation listings. But you can use HideDuplicateItems which will reduce the listings to one entry. Then when processing the results, check the flag and exclude the variation listings.
@clickimusprime Thanks for your response and for clarifying that there is no filter option! Yes thats exactly what i have currently implemented :) If someone from the ebay-team is reading this question, i would be very happy if you would implement this option.