U.S. federal prosecutors filed an appeal seeking to increase the prison sentence of the prime suspect in the HashFlare mining fraud case.

On August 27, Decrypt reported that U.S. federal prosecutors appealed to the Ninth Circuit Court of Appeals, seeking to increase the "time served" sentence for Estonian citizens Sergei Potapenko and Ivan Turõgin in the $577 million HashFlare crypto assets Ponzi Scheme case, claiming it was "exceptionally lenient." The two previously pleaded guilty to conspiracy charges, defrauding 440,000 victims globally through false mining contracts from 2015 to 2019, showcasing fictitious returns with a "fake dashboard," and using the funds for luxury items and paying early withdrawers. The judge had previously sentenced the two to only three years of supervised release and a $25,000 fine each, rejecting the prosecutors' request for 10 years in prison on the grounds of concerns over the treatment of foreign defendants in the U.S., including potential "indefinite detention." Legal experts stated that the judge's reasoning based on "time served, immigration risk, and restitution issues" was sufficient, and the Ninth Circuit typically respects the discretion of district judges, so the likelihood of the ruling being upheld is high, but a lenient sentence could undermine the deterrent effect against economic crimes. The case has seized $400 million for victim compensation and is referred to as the "largest fraud case" in the Western District of Washington.