The recent intensification of global competition in clean technologies, particularly by the U.S. and China, has driven the EU to strengthen its green industrial policy efforts. While the EU’s turn towards green market activism has been documented, there is less understanding of the coalition politics that facilitated a swift EU response in this policy area despite salient political cleavages. This paper uses an actor-centered institutionalist framework to examine the policy process that led to the adoption of the Net-Zero Industry Act (NZIA), the first European legal framework for clean technologies, as a case study of EU green industrial policy implementation. Building on document analysis and semi-structured interviews with European policymakers and stakeholders, it specifically analyses how the scope of the legislation – determining which technologies are classified as ‘net-zero’ – was constructed and negotiated by European actors, from the European Commission’s proposal in early 2023 to the Regulation’s final adoption in June 2024. This contributes to a deeper understanding of the external and domestic factors enabling and constraining EU industrial policymaking in a context of intensifying geoeconomic competition and increasing politicisation of European policymaking, as well as sheds light on the political economy of the green transition in Europe.