Sergei Potapenko & Ivan Turõgin

What the public record shows

Sergei Potapenko and Ivan Turõgin, Estonian nationals, ran HashFlare, a purported cryptocurrency-mining service. They pleaded guilty in February 2025 to conspiracy to commit wire fraud and were sentenced in August 2025 to time served (roughly 16 months already in custody), a $25,000 fine each, and community service — alongside forfeiture of assets exceeding $400 million. This is a criminal conviction — not an allegation. (Note: the ultimate sentence was lenient relative to the scale of the fraud, reflecting the plea agreement and the court’s assessment; the guilty plea and forfeiture are the operative facts.)

The scheme

According to the Department of Justice:

• Between 2015 and 2019, HashFlare sold contracts entitling customers to a share of cryptocurrency the company claimed to mine, totaling more than $577 million in sales.
• HashFlare did not possess anywhere near the computing capacity needed to perform the mining it claimed — customers were shown fake online dashboards falsely reporting mining activity and returns.
• The pair also ran a related scheme, Polybius, promising to build a bank for virtual currency and pay investors dividends; they raised at least $25 million and diverted most of it.
• Investor money funded real estate, luxury vehicles, and personal investment accounts.

Why we rate this 1 / 10 — Avoid

A guilty plea for a $577 million fraud built on a fabricated performance dashboard — customers could “see” mining results that were simply invented.

Red flags this case teaches

• Any dashboard or performance report you cannot independently verify against real, auditable infrastructure (in this case, actual computing hardware) may be entirely fictional.
• “Mining as a service” contracts, where you never see or control the actual hardware, require proof the infrastructure exists at the scale claimed.
• A related “we’re building a bank” pitch from the same operators (Polybius) is a classic sign of a promoter running multiple schemes simultaneously.

Bottom line

Convicted by guilty plea, with $400 million+ forfeited. If you can’t verify the physical infrastructure behind a “mining” or yield product, the dashboard showing your returns may be nothing more than a well-designed lie.

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