The European Securities and Markets Authority (ESMA) has published a new Trends, Risks and Vulnerabilities (TRV) article examining the implications of Maximal Extractable Value (MEV) in cryptocurrency markets. Released under ESMA’s Digital Finance and Innovation section, the article analyses how MEV practices influence crypto market operations and trading behaviour. The article finds that MEV is widespread on Ethereum and is increasing on other blockchains, although available data are limited and subject to constraints. MEV arises from the decentralised structure of blockchain systems and enables certain actors, such as miners or validators to reorder transactions within a block to maximise their own gains. While MEV may address some inefficiencies in decentralised finance (DeFi) protocols, it often results in financial losses for users and raises concerns regarding transparency, fairness and market integrity. Existing counter-measures have not resolved these issues. Although newer approaches show potential, they remain under development. ESMA emphasises the need for further research and the development of effective solutions by the crypto community to mitigate the adverse effects of MEV and support trust in DeFi and broader crypto markets.