<p>In Confidential Transactions (as used in Blockstream's Elements and Liquid), there are still identifiable UTXOs.</p>

<p>The only change is that instead of the amount, a homomorphic commitment to the amount is stored. While not technically correct, you could see it as a form of encryption that is compatible with addition and subtraction. So if <em>a+b=c+d</em> then <em>E(a)+E(b)=E(c)+E(d)</em> (where <em>E()</em> is the encryption function). This lets the verifiers still ascertain that the amounts in input and outputs match up.</p>

CC BY-SA 4.0
2018-12-05T17:54:42.790Z
2018-12-05T17:54:42.790Z
Pieter Wuille
<p>There must be magical cryptographic reason why CT doesn't create an UTXO.
If it did make an UTXO, it'd be trivial to calculate the input + output right?</p>

<privacy><utxo><confidential-transactions>
Do confidential transactions produce an UTXO
Bertram Lund
# Do confidential transactions produce an UTXO

(Asked by: username_0 on 2018-12-05)

There must be magical cryptographic reason why CT doesn't create an UTXO.
If it did make an UTXO, it'd be trivial to calculate the input + output right?

**Tags:** privacy, utxo, confidential-transactions


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## 1 answers

### Answer by username_1 on 2018-12-05. Score: 7 | Accepted answer

In Confidential Transactions (as used in Blockstream's Elements and Liquid), there are still identifiable UTXOs.

The only change is that instead of the amount, a homomorphic commitment to the amount is stored. While not technically correct, you could see it as a form of encryption that is compatible with addition and subtraction. So if *a+b=c+d* then *E(a)+E(b)=E(c)+E(d)* (where *E()* is the encryption function). This lets the verifiers still ascertain that the amounts in input and outputs match up.


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