In this paper, we consider the conditions for inhibiting the growth of precipitates from a metastable supersaturated solid solution and at the evaporation-condensation stage during spinodal decomposition of a three-component alloy. The formation of a “locking” shell around precipitates was shown to be an effective mechanism for inhibiting decomposition, provided that the solubility or diffusion coefficients of the alloy components are reduced in the shell. The thermodynamic and kinetic conditions for the appearance of such shells are formulated. The features of decomposition inhibition mechanisms in specific alloys are discussed.