Case T-556/23: Judgment of the General Court of 8 October 2025 – Swissgrid v ACER (Energy – Internal market for electricity – Guideline on electricity balancing – Article 1 of Regulation (EU) 2017/2195 – European platform for the imbalance netting process – Non-participation of the Swiss Transmission System Operator – ACER decision amending the Implementation Framework for the platform – Appeal brought before the ACER Board of Appeal – Specific conditions and arrangements for appeals – Article 28 of Regulation (EU) 2019/942 – Inadmissibility for lack of standing to bring proceedings before the Board of Appeal – Direct and individual concern)