This paper describes a content-addressed blind attestation system where an attestation server cryptographically signs the Merkle root of per-field hash commitments from a multi-field encrypted document, without the server ever accessing any plaintext field value. The resulting attestation signature is bound to the document content (Merkle root of field hashes), not to any storage location, enabling the encrypted document to be freely moved between storage backends while maintaining signature validity. Novelty claims disclosed in this publication include: (1) The first system combining blind attestation with Merkle-based selective disclosure, (2) Storage-delinked signatures where the signature is bound to content rather than storage location, (3) An explicit detach/reattach lifecycle protocol for removing and restoring server copies without re-signing, (4) Multi-provider attestation on a single Merkle root, and (5) Re-encryption resilience where signatures survive re-encryption because they are bound to plaintext hashes instead of ciphertext.
Dmitry O. Prúdnikov (Thu,) studied this question.