US prosecutors have requested a five-year prison sentence for Ilya "Dutch" Lichtenstein, the mastermind behind the infamous Bitfinex hack. Lichtenstein and his wife, rapper Heather Morgan, were charged with laundering $4.5 billion in cryptocurrency stolen from the exchange in 2016. The Justice Department had previously recommended an 18-month sentence for Morgan. The sentencing for both defendants is scheduled for next month. The Bitfinex hack was one of the largest cryptocurrency thefts in history. Prosecutors allege that Lichtenstein and Morgan used a sophisticated money laundering scheme to conceal the origin of the stolen funds. The couple faces multiple charges, including conspiracy to commit money laundering and operating an unlicensed money transmitting business. If convicted, Lichtenstein could face up to 20 years in prison. However, prosecutors are seeking a more lenient sentence, citing his cooperation with investigators and his lack of criminal history. The sentencing of Lichtenstein and Morgan will be closely watched by the cryptocurrency community. It will send a message about the consequences of cryptocurrency theft and money laundering.