Get list of users addresses that minted native asset NFT

Question

I would like to get a list of user addresses, that minted a native asset NFT. Is this possible? I do not want current holders of the NFT, but the original minting NFT holders.

Answer 1

Here's a way using the https://blockfrost.io API:

Fist you need to get the asset id, I assume you already have this because you know which NFT you want to look up.

Then you would query all transactions of this asset using the Cardano > Assets > Asset Transactions API endpoint:

https://docs.blockfrost.io/#tag/Cardano-Assets/paths/~1assets~1{asset}~1transactions/get

This returns a list of transactions, where this asset has been involved.

[
  {
    "tx_hash": "8788591983aa73981fc92d6cddbbe643959f5a784e84b8bee0db15823f575a5b",
    "tx_index": 6,
    "block_height": 69,
    "block_time": 1635505891
  },
  {
    "tx_hash": "52e748c4dec58b687b90b0b40d383b9fe1f24c1a833b7395cdf07dd67859f46f",
    "tx_index": 9,
    "block_height": 4547,
    "block_time": 1635505987
  },
  {
    "tx_hash": "e8073fd5318ff43eca18a852527166aa8008bee9ee9e891f585612b7e4ba700b",
    "tx_index": 0,
    "block_height": 564654,
    "block_time": 1834505492
  }
]

Now you take the tx_hash of the transaction with the lowest block_height and query the Cardano > Transactions > Transaction UTxOs endpoint:

https://docs.blockfrost.io/#tag/Cardano-Transactions/paths/~1txs~1{hash}~1utxos/get

This will result in an object like this:

{
  "hash": "1e043f100dce12d107f679685acd2fc0610e10f72a92d412794c9773d11d8477",
  "inputs": [ ... ],
  "outputs": [
    {
      "address": "addr1q9ld26v2lv8wvrxxmvg90pn8n8n5k6tdst06q2s856rwmvnueldzuuqmnsye359fqrk8hwvenjnqultn7djtrlft7jnq7dy7wv",
      "amount": [
        {
          "unit": "lovelace",
          "quantity": "42000000"
        },
        {
          "unit": "b0d07d45fe9514f80213f4020e5a61241458be626841cde717cb38a76e7574636f696e",
          "quantity": "12"
        }
      ],
      "output_index": 0,
      "data_hash": "9e478573ab81ea7a8e31891ce0648b81229f408d596a3483e6f4f9b92d3cf710",
      "inline_datum": "19a6aa",
      "collateral": false,
      "reference_script_hash": "13a3efd825703a352a8f71f4e2758d08c28c564e8dfcce9f77776ad1"
    }
  ]
}

Go through the outputs of this object and find the one that contains your NFT in the list of amount objects. The address of this output is the original receiver of your NFT.