<p>A lexicographical order on transaction inputs and outputs could help improve transaction homogeneity and mitigate unnecessary privacy leaks present in some wallets if adopted by the entire ecosystem.</p>
<p>However, it is unlikely to ever be adopted by a majority of wallets, because a) some transaction uses have conflicting requirements for the order of inputs and outputs, and b) many wallet developers appear to either be indifferent or opposed to BIP 69.</p>
<p>As you mention in the question, while only a minority of transactions adopts BIP 69, it represents a wallet fingerprint. My understanding is that some Bitcoin Core contributors do not support implementing BIP 69 in Bitcoin Core, and there probably also hasn’t been a contributor sufficiently invested to make it happen.</p>

CC BY-SA 4.0
2024-10-07T14:39:39.727Z
2024-10-07T14:39:39.727Z
Murch
<p>I know (I sort of get) Core Qt is currently fingerprinted by means other than <em>lexicographical analysis of order of inputs and outputs</em>.</p>
<p>And yet I suppose it could make sense to have a status label in coin control advicing whether current tentative transaction complies BIP 69 or not.</p>
<p>Can you explain why there is no such facility?<br />
Can you link Core discussions on BIP 69?<br />
Can you link any Core PR exploring the BIP 69 concepts?</p>

CC BY-SA 4.0
2024-10-02T00:25:28.710Z
https://github.com/bitcoin/bitcoin/issues/12457, https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2018-October/016457.html
Murch
<bitcoin-core><transactions><bip><coin-control>
Why aren't any BIP 69 facilities in Core Qt coin control?
Mercedes
# Why aren't any BIP 69 facilities in Core Qt coin control?

(Asked by: username_0 on 2024-10-01)

I know (I sort of get) Core Qt is currently fingerprinted by means other than *lexicographical analysis of order of inputs and outputs*.

And yet I suppose it could make sense to have a status label in coin control advicing whether current tentative transaction complies BIP 69 or not.

Can you explain why there is no such facility?  
Can you link Core discussions on BIP 69?  
Can you link any Core PR exploring the BIP 69 concepts?

**Tags:** bitcoin-core, transactions, bip, coin-control

> **Comments:**
> **username_1**: https://github.com/bitcoin/bitcoin/issues/12457, https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2018-October/016457.html  

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## 1 answers

### Answer by username_1 on 2024-10-07. Score: 1 | Accepted answer

A lexicographical order on transaction inputs and outputs could help improve transaction homogeneity and mitigate unnecessary privacy leaks present in some wallets if adopted by the entire ecosystem.

However, it is unlikely to ever be adopted by a majority of wallets, because a) some transaction uses have conflicting requirements for the order of inputs and outputs, and b) many wallet developers appear to either be indifferent or opposed to BIP 69.

As you mention in the question, while only a minority of transactions adopts BIP 69, it represents a wallet fingerprint. My understanding is that some Bitcoin Core contributors do not support implementing BIP 69 in Bitcoin Core, and there probably also hasn’t been a contributor sufficiently invested to make it happen.


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