Experimental evidence shows that the acceptor‐state levels in Sb‐doped positive‐temperature‐coefficient‐type BaTiO3are compensated up to a critical acceptor‐state density. Using the slope of the natural logarithm of the resistivity with respect to 1/T, instead of maximum resistivity as a measure for the acceptor‐state density, it is possible to estimate this critical value. The value obtained (4.2 × 1017m−2) is believed to be the first reported estimate based on experimental data. It is in good agreement with the estimate of 6 × 1017m−2(first reported by Jonker) obtained from the spontaneous polarization of BaTiO3. This shows that the ferroelectric behavior of BaTiO3is indeed a feasible explanation for the low resistivity below the Curie point, as