The Carbon Boundary Adjustment Mechanism: An Overview of the Technical and Practical Aspects of the Transitional Registry. Climate change is a global problem that requires global solutions. As the EU increases its own climate ambitions, and as less stringent climate policies prevail in many non-EU countries, there is a risk of so-called "carbon leakage". Carbon leakage occurs when EU-based companies move carbon-intensive production abroad to countries with less stringent climate policies than in the EU, or when EU products are replaced by higher-carbon imports. (More on taxation-customs.ec.europa.eu)