Member States shall ensure that from 3 March 2012:
(a) each undertaking which owns a transmission system acts as a transmission system operator;
(b) the same person or persons are entitled neither:
(i) directly or indirectly to exercise control over an under taking performing any of the functions of generation or supply, and directly or indirectly to exercise control or exercise any right over a transmission system operator or over a transmission system; nor
(ii) directly or indirectly to exercise control over a transmis sion system operator or over a transmission system, and directly or indirectly to exercise control or exercise any right over an undertaking performing any of the func tions of generation or supply;
(c) the same person or persons are not entitled to appoint mem bers of the supervisory board, the administrative board or bodies legally representing the undertaking, of a transmission system operator or a transmission system, and directly or indirectly to exercise control or exercise any right over an undertaking performing any of the functions of generation or supply; and
(d) the same person is not entitled to be a member of the super visory board, the administrative board or bodies legally rep resenting the undertaking, of both an undertaking performing any of the functions of generation or supply and a transmission system operator or a transmission system.
Source
Directive 2009/72/EC
Date 14.12.2011.