A 10 dimensional spinor has 8 degrees of freedom (it is Weyl-Majorana), and the Standard Model fermions sum 96 degrees of freedom. So 12 fermions of 8 degree of freedom each are the minimum to account for the standard model. Is there any theory, amateur or profesional, containing only this minimum for the fermion sector? (It should be OK if there is additional bosonic content, and/or of course gauge content beyond the SM). To note: -In the age of massless neutrinos, the sm only had 90 dof. So no match for it in groups of 8. -Thus, any old theory matching "12 of 8" is actually a prediction for right-handed neutrinos, and probably a prediction for massive neutrinos. But it is not very striking, because any GUT in the ways of SO(10) has it. -It is interesting, even without a theory to back it, to consider which fermions should fill a 8-tuple. First idea is to pair electron with neutrino and up with down.