Greening the Supply Chain: CSR Clauses and Codes of Conduct in Light of the Corporate Sustainability Due Diligence Directive (CS3D)

Corporate social responsibility has historically been a voluntary practice. However, in recent years, a clear shift has taken place, particularly in the national legislation of some European States: corporate responsibility as a tool for mitigating environmental and human rights impacts has progressively transitioned from the realm of voluntary commitments to legally enforceable obligations. This transformation did not occur overnight, but is the result of a long regulatory evolution, culminating in the adoption of the European Union (“EU”) Directive on Corporate Sustainability Due Diligence (hereinafter “CS3D” or “Directive”)—a subject of intense debate within the EU in recent years. The impact of this Directive extends beyond European borders. Like previous EU legal instruments, the CS3D will have extraterritorial effects, making it essential for companies outside the EU to understand its requirements; under certain conditions, indeed, non-EU companies operating within the European market will be subject to compliance obligations.This Article examines the potential implications of the transition from soft law to hard law, with a particular focus on sustainability clauses in commercial contracts and the drafting of codes of conduct. It explores how—and to what extent—the CS3D reshapes contractual governance in supply chains; the challenges associated with its implementation, particularly for small- and medium-sized enterprises (“SMEs”); and the possible unintended consequences of regulatory overreach.Section I of this Article traces the historical evolution of corporate social responsibility from voluntary initiatives to a mandatory regulatory legal framework. Section II outlines the core obligations imposed by the new CS3D. Section III examines the state of sustainability clauses and codes of conduct before the Directive’s adoption, while Section IV analyzes how they may evolve once the Directive’s mandatory provisions become applicable. Finally, Section V discusses the specific challenges faced by SMEs before concluding with a critical assessment of the Directive’s potential impact.