In my opinion (as I have stated a few times), while it is true that the bulk of the R1b was brought to Europe with the Indo-European migrations of the Eneolithic/Bronze Age, I think that there was most probably some R1b (without the L11 mutation) in Neolithic Southeast Europe brought about by widely attested (archaeologically) migrations to what is now the Bulgarian Black Sea Coast from northern Anatolia. This, in my opinion, is supported by the frequency of R1b-M269 (xL11) in SE Europe: