You don’t need to get that complicated. Just demand a list of who they sold to, then who they sold to and so on until the trail goes cold. If you can’t get an

You don’t need to get that complicated. Just demand a list of who they sold to, then who they sold to and so on until the trail goes cold. If you can’t get an answer, sanction everyone involved and you’ll find they’ll stop selling to unknown customers very quickly. It’s similar to banks and KYC rules. That was one solution off the top of my head. I’m sure the government has something more sophisticated in place that could be more effective.