{
  "id": "v21-proof-with-family-signature",
  "chapter": "06",
  "title": "a real proof carrying issuer_signature: leaf hash, inclusion, tree head, family signature, and the did:key derivation of the family key id",
  "note": "Frozen from the live production proof for tr_8e59bb9641e8 (leaf 49 of tree_size 68) plus the issuer_signature block /api/verify-receipt already serves publicly. The key_established_at ordering is advisory and is deliberately NOT part of the verdict.",
  "check": "proof",
  "input": {
    "proof": {
      "receipt_id": "tr_8e59bb9641e8",
      "leaf_index": 49,
      "tree_size": 68,
      "leaf_payload": "{\"issued_at\":\"2026-07-21T01:36:44.197Z\",\"prefix\":\"tr\",\"receipt_id\":\"tr_8e59bb9641e8\",\"sha256\":\"8e59bb9641e87b7d080a99a2dd99595ba6925e1137a602f0f16dc56b53db9a97\"}",
      "leaf_hash": "436f38bb6dd0cc0e734acc5b52b1f5accf3b47dbf96e9393e1f29f32d5aacf0c",
      "audit_path": [
        "89bd581fdd0abea59a60c3fe2eead898bb1f064117462ee492a8b163fcf07320",
        "357d8e0cf899e5bc5474a64c09505060a78e537eed132f68ac5b37a5850fc3ce",
        "a661e29666caed26a92bf142ece4c456b8ec26a182b76baf0422e2a2c17c3c69",
        "e242e096c54ae66eee623f6749cb19aaa9a9697b57e2399a21b929356f1eff5c",
        "db9b6962e43dde80d3b0212eae6075ad459712d403a940422f0007831c5943d5",
        "32fb7e1bf3dba1947eefe7eaf637bac646575617186910c63d47200c1f8a6d6f",
        "25a0d86c92df1a44a793d7c884826d4507adaac9ac07b885ddfa1ce9e9c5d9d6"
      ],
      "sth": {
        "chain_hash": "24779a0ea237d649a3158c30c0220d6df19585b7a1eb44983d3262c81ad85aa3",
        "key_id": "did:web:eformogi.com#key-1",
        "log_id": "eformogi-receipt-log-v1",
        "root_hash": "7d7772555fa389d2bd4c0192e5a0809b7ae4833e5c5aabeaff8b37bb9dd98354",
        "timestamp": "2026-09-05T04:30:46.946Z",
        "tree_size": 68,
        "version": 1,
        "signature": "z553QftbxQS5qvhGod3Je3Ud9oWjiBy5iovk7tKu8cS6wGjc6JRtT2qS3WVreirFFXhcHh2MzLbXiFWjfa1d63ZXb"
      },
      "did_document": "https://eformogi.com/.well-known/did.json",
      "issuer_signature": {
        "sig": "z3JB8S2Ak5grGzJ9Qc3dgZPPm1u9FV9xupMofQaHfMra36UPqbkwFELkNdf9Lfv3et6FKn65AP89diC8hgbEa9aXa",
        "key_id": "did:key:z6Mkq5WoP9yJiPQuyrFVgbBJDoKERPZLMe2XULmt9D3bgj49",
        "alg": "Ed25519",
        "context": "eformogi-receipt-sig-v1:",
        "public_jwk": {
          "x": "nd52QnmVbrI8iPYU4VmDpBMfKHk7hKIYa-5fXIZ9-hY",
          "crv": "Ed25519",
          "kty": "OKP"
        },
        "kb_receipt_id": "kb_39da937a793a",
        "key_established_at": "2026-07-21T01:26:37.618+00:00",
        "custody": "escrowed_by_eformogi"
      }
    }
  },
  "expect": {
    "verdict": "pass"
  }
}