Invariant measures for subshifts arising from substitutions of some primitive components

The class of substitutions of some primitive components is introduced. A bilateral subshift arising from a substitution of some primitive components is decomposed into pairwise disjoint, locally compact, shift-invariant sets, on each of which an invariant Radon measure is unique up to scaling. It is completely characterized in terms of eigenvalues of an incidence matrix when the unique invariant measure is finite.