self addressing data
Definition
While all KERI event messages are self-addressing data (SAD), there is a broad class of SADs that are not KERI events but that require signature attachments. ACDC Verifiable credentials fit into this class of SADs. With more complex data structures represented as SADs, such as verifiable credentials, there is a need to provide signature attachments on nested subsets of SADs.
(Philip Feairheller, ietf-cesr-proof)