Financial loss: Bitcoin prices historically have been highly volatile, and fluctuations could result in significant losses for investors.Fraud and cybercrime: These already have occurred. For example, in 2011, Japan-based Mt. Gox, then the largest Bitcoin exchange, experienced a security breach in which 850,000 Bitcoins worth approximately $450 million were stolen. In November 2017, a cryptocurrency called Tether reported a $31 million theft.