The properties of carbon black filled rubber compounds are greatly influenced by the extent of filler micro-dispersion. Dispersion takes place during mixing where carbon black pellets are broken up under shear forces into individual aggregates/agglomerates and distributed throughout the polymer matrix. After the mixing process, both the polymer and filler matrices can rearrange, leading to the reaglomeration of the filler network. This process is called flocculation. In this paper, flocculation is evaluated by the variation of the electrical resistivity of rubber samples aged under different conditions. A broad range of carbon black filled compounds were analyzed. Additionally, the correlation between flocculation and bound rubber was studied.