The ICJ Advisory Opinion of July 2025 goes beyond restating climate obligations and establishes a legally operative standard of integrated compliance that runs across the full landscape of multilateral environmental agreements. It operates on a spectrum of differentiation that the UNFCCC's static Annex categories cannot contain, and is already having domestic litigation consequences. While internal treaty compliance (such as filing NDCs, submitting national reports, and engaging in transparency reviews) remains necessary, it is no longer sufficient. This information brief seeks to provide an overview of the possible legal and policy implications of this opinion across the policy landscape at global level.