{
  "height": 62,
  "block_hash": "27a5ac77eba4b89643c4a8f75e22d275ff752b76ca65a751a541b2425fa6006f",
  "status": "confirmed",
  "bitcoin_block_height": 974877,
  "digest": {
    "alg": "sha256",
    "hex": "27a5ac77eba4b89643c4a8f75e22d275ff752b76ca65a751a541b2425fa6006f",
    "preimage": "block:{\"at\":\"2026-11-07T01:40:45.152Z\",\"entry_count\":1,\"first_seq\":152,\"height\":62,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":152,\"merkle_root\":\"bd43a4fc4080961358e03bc77dddd2461cbaab3a0c49bec129117b2c42e0be00\",\"prev_hash\":\"bb7edad7238c4b4536f3e8e642dfb44c0e231d75fb032a454899ee1c1ce5cb49\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T01:48:43.461Z",
      "updated_at": "2026-11-07T03:48:43.477Z",
      "bitcoin_block_height": 974880,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee837c1837597324c223853691d4b7884c134e4958e0afb8a7e0e9f1c9bb01edb2f1919fc5cc6f558de852"
        },
        {
          "type": "bitcoin",
          "block_height": 974880,
          "merkle_root": "e20917e92c25ba0bebbc60b5b7fe48f0ee84f05c3eb4987c3107d249f2c7113d"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T01:48:43.461Z",
      "updated_at": "2026-11-07T04:48:43.485Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee837d78fdbe1b11f74609ae2d0d437711b6605892e296a38043976e62ae9c6e08c5d13f8f91ccc3bf2591"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "confirmed",
      "submitted_at": "2026-11-07T01:48:43.461Z",
      "updated_at": "2026-11-07T03:48:43.477Z",
      "bitcoin_block_height": 974877,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee837d1e7b9457e6f1209cffbd4fc6bc28a9bfe1a775e87cd05312d33c939ebf21d2c6944da6326486fc03"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/62/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."
}