This is big news. What is interesting about this to me is that unlike many crypocurrency exchanges, bitmex only deals in derivatives. What this means for them is that you can only deposit BTC, and only take out BTC. So they do not give anyone USD, and they do not deposit or withdraw money from anyone's bank.<p>It is also, by far, the best way to gain leverage in cryptocurrency products, with lower fees, great security, and even a wonderful blog and transparency.<p>I'm interested to what extent the government believes the BSA needs to apply to this, since a different area of the government (IRS) decided BTC was not even a currency. Of course, all of the relevant governing bodies (of which there are <i>many</i> in the US) can all choose their own designations, which may result in apparent inconsistencies, but I wonder to what extent they were warned about this beforehand.<p>What is also interesting is that Bitmex did not allow US residents to use their exchange via blocking US IP addresses and asking for country of residence, aside from perhaps the first few months. Some US residents would use a VPN and use it instead, but they (the client) would have to lie to Bitmex in doing so. It appears that's what the argument here is - that they did a poor job, knowingly so, of stopping US residents from using their services. BitMex was, over time, implementing tougher KYC, but currently it's not required by all of their clients for a few more months.