This Regulation amends the Auctioning Regulation in three main aspects: • Aligning the Auctioning Regulation with the architecture of phase 4 of EU ETS (2021-2030) as set out in the revised ETS Directive; • Aligning the Auctioning Regulation with the financial market legislation and market oversight regime and taking into account the classification of emission allowances as financial instruments; • Incorporating lessons learned from auctioning in phase 3 of EU ETS (2013-2020).