Decentralised Supply Chain Reputation: A Privacy and Self-Sovereign Identity Perspective

Supply chain reputation systems are critical in determining product quality and auditing regulatory compliance throughout the supply chain lifecycle. This paper conducts a systematic review of blockchain-based reputation systems in supply chains, evaluating their alignment with privacy and self-sovereign identity (SSI) principles. By analysing literature published between January 2022–2025, we identify critical gaps in existing frameworks, including fragmented trust mechanisms, reliance on centralised authorities, and insufficient integration of SSI for end-to-end accountability. Our findings reveal that while blockchain enhances transparency and immutability, challenges persist in balancing privacy setting including data minimisation and sovereignty with regulatory compliance. We propose future directions such as hybrid reputation models, decentralised identity governance, and interoperable incentive structures to bridge these gaps, fostering resilient and user-centric supply chains in Industry 4.0.