The paper deals with MSiBCN (M = Ti, Zr, Hf) thin films prepared by pulsed dc reactive magnetron sputtering of M15Si20(B4C)(65) targets. We focus on the effect of M choice and N-2 + Ar discharge gas mixture composition. The experimental results are complemented and explained by ab-initio calculations. We find that the transition from Ti through Zr to Hf leads to (i) increasing driving force towards segregation, (ii) weaker role of M around the Fermi level and opening of a wider band gap in N-rich compositions, (iii) higher electrical resistivity and lower extinction-coefficient in N-rich compositions, (iv) increasing energy resulting from the oxidation of constituent M-containing phases, and consequently decreasing oxidation resistance of N-poor compositions and (v) increasing oxidation resistance of N-rich compositions. The results are important for the design of future coatings with tailored combinations of mechanical, electrical and optical properties and oxidation resistance. (C) 2016 Elsevier B.V. All rights reserved.