In order to facilitate the emergence of well functioning and trans? parent retail markets in the Community, Member States shall ensure that the roles and responsibilities of transmission system operators, distribution system operators, supply undertakings and customers and if necessary other market parties are defined with respect to contractual arrangements, commitment to customers, data exchange and settlement rules, data ownership and metering responsibility.
Those rules shall be made public, be designed with the aim to facilitate customers’ and suppliers’ access to networks and they shall be subject to review by the regulatory authorities or other relevant national authorities.
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