http://pandodaily.com/2013/05/17/bitcoin-is-legal-but-mainstream-adoption-will-mandate-playing-by-the-rules/A number of questions remain unanswered regarding the current Department of Homeland Security (DHS) case against Mt. Gox in particular. But contrary to the concerns of many conspiracy theorists, a paper published in March by the Financial Crimes Enforcement Network (FinCEN) makes it clear that decentralized digital currencies, such as bitcoin, are legal. (The agency also opined on other alternative currencies such as e-currencies, e-precious metals, and centralized digital currencies.)