Spain's national competition and markets regulator, the CNMC (Comisión Nacional de los Mercados y la Competencia), has opened sweeping sanctions proceedings against multiple companies and power installations in connection with the nationwide blackout of 28 April 2025, which cut electricity supply across the entire Iberian Peninsula. The regulator says it has identified evidence of possible violations of Spain's Electricity Sector Law by a wide range of facilities — including renewables, gas combined-cycle plants, and nuclear stations — though it has not named those under investigation and stresses that the blackout had multifactorial causes, meaning sanctions would not automatically imply responsibility for the outage itself. The announcement comes less than two weeks before the first anniversary of the blackout, a legally significant deadline after which affected companies — including energy firm Repsol and insurer Mapfre, which have signalled intentions to seek hundreds of millions of euros in damages — can begin filing claims in court.