The option expiry on Wednesday acted as a volatility suppressant rather than a catalyst. Weekly turnover in the December 2025 contract eased to 184 million tonnes (Mt). Once the expiry cleared, prices pushed higher to EUR84.40 before a second attempt on Friday faded into consolidation. The review of 2025 in the EU ETS highlights the structural impact of major regulatory resets such as the Market Stability Reserve in 2018 and the Green Deal in 2021. The drawdown and draw-up profile shows that political and regulatory interventions have historically skewed risk to the upside. Investor positioning reached record levels in EUR terms in September and a new all-time high in terms of physical exposure (i.e., in tonnes) in December. Auction supply is set to decline materially from 2026, a structural tightening that should underpin EUA prices. Such a shift would be critical in unlocking both physical decarbonisation investments and longer-dated forward purchasing. What does this mean for the market? We remain constructive on EUAs and the "trend remains our friend."