One of the most important aspects of cryptocurrencies from a civil liberties perspective is that they can provide privacy protections for their users. But EFF is concerned that the U.S. government has been increasingly taking steps to undermine the anonymity of cryptocurrency transactions and importing the widespread financial surveillance of the traditional banking system to cryptocurrencies. On Friday, the Department of the Treasury’s Financial Crimes Enforcement Network (FinCEN) announced a proposed regulation that would require money service businesses (which includes, for example, cryptocurrency exchanges) to collect identity data about people who transact with their customers using self-hosted cryptocurrency wallets or foreign exchanges. The proposed regulation would require them to keep that data and turn it over to the government in some circumstances (such as when the dollar amount of transactions in a day exceeds a certain threshold).