<p>It would be rejected.  The coinbase input must use a very specific previous <a href="https://bitcoin.org/en/developer-reference#raw-transaction-format" rel="nofollow">outpoint</a>: <code>0x0000000000000000000000000000000000000000000000000000000000000000ffffffff</code>. This prevents it from referring to an actual previous outpoint.</p>

CC BY-SA 3.0
2014-11-22T20:21:50.943Z
2014-11-22T20:21:50.943Z
David A. Harding
<p>I know the coinbase transaction's input is usually just has a dummy <code>scriptSig</code>, but what if a miner used it to spend an UTXO? Would it be verified as an actual spend, or would the block be rejected?</p>

<mining-reward><utxo>
Can the coinbase transaction be used to spend an UTXO?
morsecoder
# Can the coinbase transaction be used to spend an UTXO?

(Asked by: username_0 on 2014-11-22)

I know the coinbase transaction's input is usually just has a dummy `scriptSig`, but what if a miner used it to spend an UTXO? Would it be verified as an actual spend, or would the block be rejected?

**Tags:** mining-reward, utxo


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## 1 answers

### Answer by username_1 on 2014-11-22. Score: 4 | Accepted answer

It would be rejected. The coinbase input must use a very specific previous [outpoint](https://bitcoin.org/en/developer-reference#raw-transaction-format): `0x0000000000000000000000000000000000000000000000000000000000000000ffffffff`. This prevents it from referring to an actual previous outpoint.


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