Cyclic 1,3,5,7-tetrakis(trimethylsilyl) tetraphenyltetrasilsesquioxane (T4OTMS), 3,7,14-tris(trimethylsilyl)heptaphenyltricyclo[7.3.3.1(5,11)]heptasilses quioxane (T7OTMS), and 5,11,14,17-tetrakis(trimethylsilyl)octaphenyltetracyclo[7.3.3.3(3,7)]oct asilsesquioxane (DDT8OTMS) were found to be formed by the hydrolysis of completely condensed polyhedral oligomeric silsesquioxanes (POSS) followed by trimethylsilyl (TMS)-capping. The reaction was shown to be a reshuffling process by the scrambling of substitutents in co-hydrolysis of differently substituted POSS.