Functional Differentiation and Prospective Compatibility Between the CPTPP and IPEF: Evidence from Indo-Pacific Labour and Supply-Chain Governance

This article examines whether treaty-based and cooperation-oriented institutions can perform complementary functions in Indo-Pacific economic governance. It compares the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) and the Indo-Pacific Economic Framework for Prosperity (IPEF), while treating the Regional Comprehensive Economic Partnership (RCEP) and other regional mechanisms as contextual alternatives. Drawing on a structured 53-document corpus of legal, policy, institutional, scholarly, and project-level materials, the study maps overlapping participation and agreement-specific legal status, then analyses labour and supply-chain governance in Malaysia and Vietnam and an attribution boundary case on clean-energy cooperation in Indonesia. It develops selective complementarity as an issue-specific evaluative framework distinguishing thematic overlap, functional differentiation, prospective compatibility, operational interaction, and institutionalised interaction. The findings show functional differentiation and prospective compatibility in Malaysia and Vietnam, but no cross-framework linkage, transmission, uptake, or additional implementation value was documented within the defined corpus and period. Indonesia demonstrates that policy alignment does not convert bilateral, development-finance, or adjacent regional initiatives into IPEF activities. Japan is best understood as a cross-case facilitating actor because the evidence does not establish a stable bridging mechanism between the two frameworks. By setting clear evidentiary thresholds and identifying evidence that would count against complementarity, the study contributes to research on regime complexity, institutional interaction, and sustainability-oriented regionalism.