The Independent Power Transmission Operator (IPTO or ADMIE) S.A. undertakes the role of Transmission System Operator for the Greek Electricity Transmission System. As such, IPTO performs the duties of System operation, control, maintenance and development so as to ensure Greece’s electricity supply in an adequate, safe, efficient and reliable manner. Furthermore, IPTO operates the Greek electricity market in accordance with the principles of transparency, equality and free competition. The shareholder structure of IPTO is as follows: - 51% ADMIE HOLDING S.A. - 25% DES ADMIE S.A. - 24% State Grid Europe Limited