This guidance developed by ISEAL on Chain of Custody (CoC) Models and Definitions is a reference document for sustainability standards systems that complements ISEAL's Sustainability Claims Good Practice Guide.
The ISEAL Chain of Custody Models and Definitions Guidance provides a shared baseline reference for different Chain of Custody (CoC) models, supporting consistency in understanding and implementation across different industries and sustainability systems.
Since its initial publication in 2016, the guidance has served as a valuable resource for organisations seeking to align CoC models with credible sustainability claims. In 2024, we launched a revision process and public consultation to ensure the guidance remains relevant and practical for today’s shifting traceability landscape. The updated guidance was introduced during a launch webinar in July 2025. The 2025 guidance reflects this evolving traceability landscape and includes:
- New models like Controlled Blending and Controlled Mass Balance
- Clarified definitions and key concepts
- Lots of practical diagrams to support learning and application across sectors
This guidance is aligned and complementary to the ISEAL Code of Good Practice for Sustainability Systems (‘the ISEAL Code’). It can be used as a reference to understand the different CoC models used in sustainability systems, which can help support a consistent understanding of ISEAL Code requirements relevant to CoC. It also identifies conditions under which each CoC model is appropriate for different supply chains, which can help inform discussions about which strategies may be relevant to specific clauses in the ISEAL Code. For example, truthfulness of allowed claims (8.2) and chain of custody (8.4).
For more information and related resources, visit the Chain of Custody Models and Definitions Guidance information page