{
  "height": 41,
  "block_hash": "eb5dccf6f00a5a26cc442f12378d31ac5a1572fb0370cf57643b70719ae244c5",
  "status": "confirmed",
  "bitcoin_block_height": 974874,
  "digest": {
    "alg": "sha256",
    "hex": "eb5dccf6f00a5a26cc442f12378d31ac5a1572fb0370cf57643b70719ae244c5",
    "preimage": "block:{\"at\":\"2026-11-07T00:49:14.902Z\",\"entry_count\":2,\"first_seq\":119,\"height\":41,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":120,\"merkle_root\":\"f86732ec743fafe7406ac8ed9ab81a8c7eec673d74ae5fb3a12ca485875789df\",\"prev_hash\":\"45f2b1657391f919af26bfca46d1f95b5e86adeaa6bde2d2b925a00513e64194\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T00:58:43.456Z",
      "updated_at": "2026-11-07T02:58:43.471Z",
      "bitcoin_block_height": 974874,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee77c4a81d5de98c4c2b6f9fdd2b3563349f20c2b0100c3097eb695b4774be21eeb00755bcd1417e656090"
        },
        {
          "type": "bitcoin",
          "block_height": 974874,
          "merkle_root": "fa522f272a37cb03554d5be30f11a1564362627a0d248c198befb5a303c3a302"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "pending",
      "submitted_at": "2026-11-07T00:58:43.456Z",
      "updated_at": "2026-11-07T00:58:43.456Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee77c42db8cd8db3de835d0a5f2aee4b17cc2f0f50575eb84c8bd0f03abcf86c39ae5af6396e9bebd6f82e"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "pending",
      "submitted_at": "2026-11-07T00:58:43.456Z",
      "updated_at": "2026-11-07T00:58:43.456Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee77c3d159bb737dc45b3a5301fcf0f31af91842411fe8ac2229615b64146e745f0336d2eeebe2f15a5ba0"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/41/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."
}