The Council of the EU has adopted a new regulation to reinforce market surveillance against manipulations and ensure open and fair competition in the wholesale energy markets. This Regulation amends the Regulation on wholesale energy market integrity and transparency, Regulation (EU) 1227/2011 (the REMIT regulation) and the Regulation on the establishment of ACER, Regulation (EU) 2019/942. It creates clearer and stricter requirements for market participants in the EU who are resident in a third country who will have to designate, through a written mandate, a representative in a Member State in which they are active in the wholesale energy market. Also, this new Regulation gives the European Union Agency for the Cooperation of Energy Regulators (ACER) the right to investigate cases with a cross-border dimension, where at least two Member States are affected although national regulatory authorities will have up to three months to object to the exercise of ACER’s investigatory powers when these have been formally initiated or an investigation has been conducted based on the same facts. The power to impose fines for infringements or breaches of the prohibitions or substantive obligations included in the Regulation will remain in the hands of the Member States. The Regulation will enter into force 20 days after publication in the Official Journal of the EU.