The appearance of a maximum in the intensity of scattered light at a nonzero wave vector for systems undergoing a polymerization-induced phase separation (PIPS) has been considered in the past as conclusive evidence of the presence of a spinodal demixing mechanism. However, recent results from Light scattering studies of colloidal aggregation and phase separation in aqueous biopolymers systems and polymer blends prove that the maximum may also be generated by a nucleation-growth process (NG). The origin of this scattering behavior is the presence of a layer surrounding dispersed-phase particles that contains less solute concentration than the bulk (depletion layer). We apply this concept to a system undergoing PIPS through an NG mechanism. The analysis is constrained to the generation of a diluted dispersion of spherical particles where concentration profiles around particles may be analytically derived. Both Rayleigh-Gans and Mie scattering theories are used to describe the patterns of scattered light. It is shown that in a diffusion-controlled growth process a maximum will appear in the scattered light pattern at a nonzero wave vector. This maximum increases in intensity and shifts to lower values of the wave vector as the population of particles grows. For particular cases where the continuation of nucleation leads to a decrease in the average size of the particles, the maximum may shift to higher values of the wave vector, as recent experimental evidence has demonstrated. For the diluted dispersion, situations where the usual patterns ascribed to NG are obtained, i.e., scattered intensity decaying from the zero wave vector, are (a) the absence of diffusion control in the growth process, (b) starting solutions that are very diluted in the component that will be phase separated, and (c) generation of a very broad distribution of particle sizes.