With the adoption of EU Directive 959/2023, the scope of the European Trading System (ETS) has been extended to international maritime navigation. Following a usual pattern in this régime, the Directive sets out mandatory reduction targets, made more flexible by the possibility to allocate free GHG allowances, while establishing the application of a 50% share for journeys between an EU member state and a third state. At the same time, the adoption of a global market-based measure has been the object of attention within IMO, whose mandate and institutional setting, in contrast, assign a more prominent role to the principle of non-discrimination and to the integrity of obligations, including those relating to emission reduction. The adoption of a global emission trading scheme for shipping is therefore likely to be fraught with difficulties stemming, inter alia, from a fragmented vision of the ultimate purpose of economic measures in climate regulation, as well as from the ‘competitiveness concern’ that constitutes one of the main features of the ETS.
