<p>Yes, that method would work. It only works if the 0.1 BTC that you use as taint was mined after the fork. If it was from before the fork, then the transactions can still be replayed.</p>

CC BY-SA 3.0
2017-07-12T01:19:39.123Z
2017-07-12T01:19:39.123Z
Ava Chow
<p>I've got a very precise question about (self-)protection vs replay attacks in Bitcoin but to clearly explain myself, I need to explain what I did with Ethereum. </p>

<p>When the Ethereum fork happened (ETH / ETC) I did split my ETH / ETC myself.  At first I failed (my tx got replayed on both chains, but I was in control of all the addresses, including the destination address) and then I did it like this:</p>

<ul>
<li>I had 2500 ETH pre-fork on a single address, so post post fork I had 2500 ETH and 2500 ETC.</li>
<li>sent 5 ETHs on the ETH chain only</li>
<li>Move 2505 ETHs to an ETH-only wallet</li>
<li>Move 2500 ETC to an ETC-only wallet</li>
</ul>

<p>My thinking was that the tx to move 2505 ETH on the ETH chain wouldn't be replayable (because on the ETC chain I had only 2500 ETC, not 2505 ETC) and, surely enough, this time it worked. </p>

<p>I know that there were other ways to achieve the same result but that's how I choosed to do it because I really liked the idea of creating a tx that wouldn't be valid on the other chain.</p>

<p>However I'm not familiar enough with Bitcoin and UTXO and what precisely makes a tx nor how it is signed to understand how this would work under Bitcoin.</p>

<p>If there's one (or several) hard fork, can I use the same technique to "split the BTCs" myself?</p>

<p>For example if I have 80 BTC on a hierarchical deterministic wallet (Ledger Nano S in my case), can I send 0.1 BTC there, then move 80.1 BTC and be sure this movement of 80.1 BTC is not going to be replayable on the fork where I still only have 80 BTC?</p>

<p>Would that work?</p>

<p>Note that this question is not: <em>"How do I split my coins in case of a hardfork?"</em> but <em>"Would this particular method of splitting work on Bitcoin too, just liked it worked for me on Ethereum?"</em></p>

<transactions><signature><blockchain-fork><utxo>
How to create a tx that cannot be replayed?
Cedric Martin
# How to create a tx that cannot be replayed?

(Asked by: username_0 on 2017-07-12)

I've got a very precise question about (self-)protection vs replay attacks in Bitcoin but to clearly explain myself, I need to explain what I did with Ethereum.

When the Ethereum fork happened (ETH / ETC) I did split my ETH / ETC myself. At first I failed (my tx got replayed on both chains, but I was in control of all the addresses, including the destination address) and then I did it like this:

* I had 2500 ETH pre-fork on a single address, so post post fork I had 2500 ETH and 2500 ETC.
* sent 5 ETHs on the ETH chain only
* Move 2505 ETHs to an ETH-only wallet
* Move 2500 ETC to an ETC-only wallet

My thinking was that the tx to move 2505 ETH on the ETH chain wouldn't be replayable (because on the ETC chain I had only 2500 ETC, not 2505 ETC) and, surely enough, this time it worked.

I know that there were other ways to achieve the same result but that's how I choosed to do it because I really liked the idea of creating a tx that wouldn't be valid on the other chain.

However I'm not familiar enough with Bitcoin and UTXO and what precisely makes a tx nor how it is signed to understand how this would work under Bitcoin.

If there's one (or several) hard fork, can I use the same technique to "split the BTCs" myself?

For example if I have 80 BTC on a hierarchical deterministic wallet (Ledger Nano S in my case), can I send 0.1 BTC there, then move 80.1 BTC and be sure this movement of 80.1 BTC is not going to be replayable on the fork where I still only have 80 BTC?

Would that work?

Note that this question is not: *"How do I split my coins in case of a hardfork?"* but *"Would this particular method of splitting work on Bitcoin too, just liked it worked for me on Ethereum?"*

**Tags:** transactions, signature, blockchain-fork, utxo


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## 1 answers

### Answer by username_1 on 2017-07-12. Score: 1

Yes, that method would work. It only works if the 0.1 BTC that you use as taint was mined after the fork. If it was from before the fork, then the transactions can still be replayed.


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