  We present a systematic study of galaxy biasing in the presence of primordial
non-Gaussianity. For a large class of non-Gaussian initial conditions, we
define a general bias expansion and prove that it is closed under
renormalization, thereby showing that the basis of operators in the expansion
is complete. We then study the effects of primordial non-Gaussianity on the
statistics of galaxies. We show that the equivalence principle enforces a
relation between the scale-dependent bias in the galaxy power spectrum and that
in the dipolar part of the bispectrum. This provides a powerful consistency
check to confirm the primordial origin of any observed scale-dependent bias.
Finally, we also discuss the imprints of anisotropic non-Gaussianity as
motivated by recent studies of higher-spin fields during inflation.
