user119973: Due to the recent change in regulatory bodies, crypto businesses are now being asked to prevent their customers from facilitating transactions used for money laundering and other illicit activities such a purchasing illegal goods or services. A preventative measure called Know Your Transaction (KYT) has become a necessity to combat this.
KYT services use on-chain analysis to determine if a sender's address is high or low risk.
However I have recently come across the issue that some bitcoin transactions appear to have multiple input addresses (example). I have read some posts here outlining that it is difficult to determine the true sender address from one of these transactions.
I would like to know if providing one of the sender addresses is good enough for the KYT service to determine if the transaction is high risk, or should I attempt to pass each of the sender addresses (for multi-sender transactions) as separate transactions. One drawback of the latter is that we pay per usage for each sender address, so it would result in higher fees.
I would like to point out that:

I am using Coinbase Analytics
I'm not sure if this is relevant but the transaction occurs on-chain and if it is flagged as high risk we would return the BTC to the customer


user13866: 
I would like to know if providing one of the sender addresses is good enough for the KYT service to determine if the transaction is high risk

I don't see how it could be good enough. If one of the other sender addresses is high risk, your service would give a false result. Wouldn't you knowingly have failed to adequately assess the risk and thereby aided in the processing of criminally obtained funds? At the least it seems negligent.
However I am not a KYT compliance officer, just some random person in the Internet. You should probably instead ask both your KYT service and a lawyer.

119973: <p>Due to the recent change in regulatory bodies, crypto businesses are now being asked to prevent their customers from facilitating transactions used for money laundering and other illicit activities such a purchasing illegal goods or services. A preventative measure called Know Your Transaction (KYT) has become a necessity to combat this.</p>
<p>KYT services use on-chain analysis to determine if a sender's address is high or low risk.</p>
<p>However I have recently come across the issue that some bitcoin transactions appear to have multiple input addresses (<a href="https://www.blockchain.com/btc/tx/6faef7b9cd63eaaa217006f6f52c2a42c898842987167bdd36331eac3413423b" rel="nofollow noreferrer">example</a>). I have read some posts here outlining that it is difficult to determine the true sender address from one of these transactions.</p>
<p>I would like to know if providing one of the sender addresses is good enough for the KYT service to determine if the transaction is high risk, or should I attempt to pass each of the sender addresses (for multi-sender transactions) as separate transactions. One drawback of the latter is that we pay per usage for each sender address, so it would result in higher fees.</p>
<p>I would like to point out that:</p>
<ol>
<li>I am using Coinbase Analytics</li>
<li>I'm not sure if this is relevant but the transaction occurs on-chain and if it is flagged as high risk we would return the BTC to the customer</li>
</ol>
 13866: <blockquote>
<p>I would like to know if providing one of the sender addresses is good enough for the KYT service to determine if the transaction is high risk</p>
</blockquote>
<p>I don't see how it could be good enough. If one of the other sender addresses is high risk, your service would give a false result. Wouldn't you knowingly have failed to adequately assess the risk and thereby aided in the processing of criminally obtained funds? At the least it seems negligent.</p>
<p>However I am not a KYT compliance officer, just some random person in the Internet. You should probably instead ask both your KYT service and a lawyer.</p>
