European Contract Law in Transition: Privity and Value Creation under the Corporate Sustainability Due Diligence Directive

The thesis examines how the EU Corporate Sustainability Due Diligence Directive (CSDDD) affects European contract law, and how firms established within the Internal Market can create value based on the CSDDD and its underlying climate law principles. Thus, the thesis is situated at the intersection of European contract law and the EU climate framework. It is structured as a paper-based dissertation consisting of three articles placed within a cappa. It centres on the overall research question: How does the CSDDD affect European contract law, explicitly focusing on the principle of privity of contract, and how can the firms established within the Internal Market create value based on the CSDDD and its underlying climate law principles? This question is addressed through three sub-questions corresponding to the three articles: I) How do Articles 10 and 11 of the EU Corporate Sustainability Due Diligence Directive affect the doctrine of privity of contract in European contract law? II) What effect does the Corporate Sustainability Due Diligence Directive have on the doctrine of third-party beneficiary claims? III) How can the contractual framework support value creation within the EU's climate legislation framework? Methodologically, the thesis adopts transnational legal pluralism as its analytical lens, supplemented by insights from legal positivism, and combines legal analysis with applied economics. The unit of analysis is the contract concluded by a lead firm within the Internal Market and the chain of activity through which CSDDD-compliant codes of conduct and contractual assurances are cascaded. The dissertation is structured in three parts: Part I: The Subject, Methodology, and Structure of the Dissertation; Part II: The Three Articles; Part III: Omnibus and Conclusion. Part I sets out the subject, methodology, and legal framework and comprises three chapters. Chapter 1 introduces the relevance of the CSDDD as a shift from corporate governance to contractual governance in global value chains; formulates the overall research question and sub-questions; defines core concepts, including European contract law, sustainability, climate, and the chain of activity; and presents the overall structure. Chapter 2 presents transnational legal pluralism and the applied economic approach, specifically strategic contracting, explaining how overlapping legal and contractual norm systems generate tensions of validity and legitimacy when obligations set out in CSDDD penetrate chain-internal norms. Chapter 3 maps the legal framework, defining European contract law as an overlapping core of national contract laws, EU law, soft law instruments such as the Principles of European Contract Law (PECL) and Draft Common Frame of Reference (DCFR), and scholarly work on common principles, and situates the CSDDD within the layered EU climate regime derived from the international climate framework. Part II contains the three articles. Chapter 4 analyses the principle of privity of contract and its main exemptions, and argues that, within its scope, the CSDDD operates as a lex generalis framework for exemptions from privity in business-to-business relationships by mandating appropriate measures such as contractual assurances and targeted SME support along chains of activity. Chapter 5 examines third-party beneficiary claims as an exemption to the principle of privity and shows how obligations arising from the CSDDD that must be embedded in codes of conduct and contracts can potentially constitute a right and inform the interpretation of intention, arguably making such claims more straightforward to establish in some settings, while remaining contingent on national legal systems and judicial interpretation. Chapter 6 situates strategic contracting within the EU climate framework and argues that contracts, when designed around resource complementarity, strategic fit, knowledge exchange, and relationship-specific investments, can function as complementary governance mechanisms that both cascade CSDDD obligations and create economic and environmental value. Part III is the last part of the thesis. Chapter 7 analyses the implications of the Omnibus amendments adopted on 16 December 2025 and reflects on their impact on the analyses and findings in this thesis. Chapter 8 concludes the thesis. The main findings are that the CSDDD transitions contracts from primarily private ordering towards also having a more regulatory role in EU climate and sustainability governance. It shows that the Directive establishes a general framework for exemptions from privity, increases the potential role of third-party beneficiaries, and creates a regulatory environment in which strategic contracting can, in principle, turn compliance with due diligence obligations into a source of value creation for firms within the Internal Market, while emphasising that the realisation of these potentials remains structurally contingent on transposition, judicial practice, and contracting behaviour.