The European Commission published a new registry regulation for Phase IV of the EU ETS this summer (New Registry Regulation)i . The publication of the New Registry Regulation appears to have hardly been noticed. The New Registry Regulation came into force on 22 July 2019. It partially amends Commission Regulation (EU) No. 389/2013 (the current Registry Regulation) (effective immediately) and, from 1 January 2021, will entirely replace the current Registry Regulation in respect of EU ETS transactions. We summarise below some of the key points to note from this development.