Green Rules, Fragmented Fields: Member-State Approaches to Sustainability in EU Competition Law

This article provides a comparative, normative-evaluative examination of how sustainability is being incorporated into European competition law. Combining doctrinal legal analysis with economic reasoning, it clarifies competing definitions of sustainability, maps the contest between the consumer-welfare paradigm and sustainability proponents, and evaluates the legal and institutional implications of the Commission’s 2023 Horizontal Cooperation Guidelines. Drawing on national initiatives across Member States plus the UK, the study highlights contrasting instruments, from Austria’s statutory environmental exemption to the Dutch soft-law safe harbour and Greece’s experimental sustainability sandbox, and shows how these divergent approaches produce fragmentation and legal uncertainty for cross-border cooperative initiatives. It concludes that competition law cannot substitute for sector-specific sustainability regulation but can materially support the Green Deal if EU and national authorities harmonise standards, specify clear evidentiary criteria for exemptions and enforcement, and deploy pragmatic tools, including coordinated ECN guidance, together with targeted enforcement practices to reconcile sustainability objectives with market predictability.