{
  "height": 67,
  "block_hash": "f0a060aa9e784551f5cbc2b804923a65340833b57e4d871754fab03f981615ce",
  "status": "confirmed",
  "bitcoin_block_height": 974880,
  "digest": {
    "alg": "sha256",
    "hex": "f0a060aa9e784551f5cbc2b804923a65340833b57e4d871754fab03f981615ce",
    "preimage": "block:{\"at\":\"2026-11-07T01:52:15.184Z\",\"entry_count\":1,\"first_seq\":159,\"height\":67,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":159,\"merkle_root\":\"2790d81c947d8379e8fffa9d3fc2540964b325219cbc153951379efefecf16b7\",\"prev_hash\":\"c04f96262bc0e5072a528fb99a52e33dc28371e6306aed93a4c726c083a12ebd\",\"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": "6aee85d43897e675d9d2e781b504ee5092aec0882adf8d7e6b9feec185bd233d224fac25f7bc0ae3fc9e36e0"
        },
        {
          "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": "6aee85d531d9aad4e97c7e9a206f5b4cd8f5bec30d48bcf3f35077730f4a6505414efe4b6f44505c859f30d9"
        },
        {
          "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": "6aee85d59fb347e1f1378c9cd71e7be4eded4c4a6055d587b916f92bffe9f884544a0ddeab3d5e9ee023fef3"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/67/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."
}