Fraunhofer SIT Microsoft Microsoft Microsoft A transparent and authentic Transparent Registry service in support of a supply chain's integrity, transparency, and trust requires all peers that contribute to the Registry operations to be trustworthy and authentic. In this document, a countersigning variant is specified that enables trust assertions on Merkle-tree based operations for global supply chain registries. A generic procedure for producing payloads to be signed and validated is defined and leverages solutions and principles from the Concise Signing and Encryption (COSE) space.