The TEM method is of broad use in oil and gas exploration in southern Siberian Craton, with about ten thousand soundings acquired yearly. The multi-offset TEM systems with 500 - 600 m square loops, which have been in use recently, can reveal also induced polarization (IP). IP-affected TEM data make about 75 % of the total amount of transient responses recorded in the area. The IP effects can be estimated qualitatively from difference between the right-hand branches of apparent resistivity curves obtained with in-loop and off-loop configurations. Processing of these data consists of several steps. First, TEM responses at reference points within the study area are inverted in a semi-automatic mode with IP effects included in terms of the Cole-Cole model. The polarization parameters of the resulting reference models are interpolated over the whole area with regard to difference between in-loop and off-loop responses. The equivalence is reduced by locking two out of four Cole-Cole parameters (most often c and τ).