{
  "height": 68,
  "block_hash": "c4c3c19b59c154726f3b092defc0da327b32a59a1d21f8cdea8fcb556b69628f",
  "status": "confirmed",
  "bitcoin_block_height": 974880,
  "digest": {
    "alg": "sha256",
    "hex": "c4c3c19b59c154726f3b092defc0da327b32a59a1d21f8cdea8fcb556b69628f",
    "preimage": "block:{\"at\":\"2026-11-07T01:54:15.190Z\",\"entry_count\":2,\"first_seq\":160,\"height\":68,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":161,\"merkle_root\":\"a45e877dcd592ced14bf7ea6e0e92d2eca0fd4bd8610d1938da4ed4085dd8737\",\"prev_hash\":\"f0a060aa9e784551f5cbc2b804923a65340833b57e4d871754fab03f981615ce\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T01:58:43.462Z",
      "updated_at": "2026-11-07T03:58:43.477Z",
      "bitcoin_block_height": 974880,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee85d530b38540f24a7c72b3e2dd2628b2df9ee7b0301225892978f3ad64fc8f3f6eed85e32510c125f85c"
        },
        {
          "type": "bitcoin",
          "block_height": 974880,
          "merkle_root": "e20917e92c25ba0bebbc60b5b7fe48f0ee84f05c3eb4987c3107d249f2c7113d"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T01:58:43.462Z",
      "updated_at": "2026-11-07T04:58:43.484Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee85d67c5cea1ddd2cddb9a22e82915f14b60df4dc244f5bd067a49419baf0387211273e8ecaaa32841956"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "pending",
      "submitted_at": "2026-11-07T01:58:43.462Z",
      "updated_at": "2026-11-07T01:58:43.462Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee85d6eccc4d7197f1d7142928ea78b3cd2abc9591dab40253a67eddd9fb966fa4c98c7e0be220d74b2cce"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/68/anchor.ots",
  "how_to_verify": "Download the .ots proof and run `ots verify -d <block_hash> <file>.ots` with the OpenTimestamps client, which checks the Bitcoin attestation against Bitcoin block headers. The digest is the block hash: sha256 of digest.preimage, the text \"block:\" followed by the canonical block header, which is the same header the issuer signs."
}