In light of the growing complexities of data-driven digital markets, traditional ex-post competition laws are often insufficient, prompting many jurisdictions to adopt ex-ante regulatory frameworks. This paper examines the compatibility of ex-ante competition regulations, such as the European Union’s Digital Markets Act (DMA), with the General Agreement on Trade in Services (GATS), focusing on the potential violation of national treatment and most-favoured-nation obligations. The paper critiques the Appellate Body’s narrow approach in Argentina–Financial Services, which limits the consideration of regulatory intent in the GATS non-discrimination analysis. It advocates for a broader approach that integrates regulatory purpose in assessing ‘likeness’ and ‘less favourable treatment’. The paper concludes that such a perspective would ensure that ex-ante competition regulations, like the DMA, can be justified under GATS without undermining fair competition, while allowing states to regulate digital markets effectively.