South Dakota crypto investor indicted over $20M Ponzi scheme
Federal prosecutors have charged a South Dakota investor with running a $20 million cryptocurrency Ponzi scheme, adding to a widening crackdown on digital-asset fraud by US authorities.
A federal grand jury has indicted Benjamin Paul Wiener on 29 counts of wire fraud, money laundering, bank fraud, and aggravated identity theft tied to an alleged $20 million fraud scheme. Wiener, a 43-year-old Sioux Falls resident, appeared before US Magistrate Judge Veronica L. Duffy on July 10 and pleaded not guilty to the charges. He was released on bond ahead of a scheduled September 15 trial.
Prosecutors allege Wiener operated a Ponzi structure using eight separate entities, including several limited liability companies. He used materially false statements to collect both fiat currency and digital assets from dozens of victims located across South Dakota and Minnesota. When existing investors requested their capital back or the pool of funds dwindled, Wiener allegedly tapped new investors to satisfy the earlier obligations.
To hide the movement of capital, authorities claim Wiener routed the funds through traditional financial institutions and cryptocurrency exchanges, obscuring the source, ownership, and control of the money before spending it on personal expenses. The indictment also highlights a specific bank fraud count originating in April 2025. Wiener allegedly falsified documents and used another individual's identifying information without authorization to secure a $1 million line of credit from a Sioux Falls financial institution.
The legal exposure for the alleged crimes is substantial. Wire fraud and money laundering each carry maximum prison sentences of 20 years, while the bank fraud count carries a 30-year maximum. Furthermore, the aggravated identity theft charge mandates a minimum two-year sentence that must run consecutively to any other imposed penalties.
This prosecution arrives amid a visible acceleration in federal enforcement actions targeting cryptocurrency-related fraud. In February, authorities charged a New England man who posed as a successful crypto investor before losing nearly $1 million of victim funds on the offshore gambling platform Stake.com. In June, a Washington state resident received a five-year prison sentence for his role in laundering nearly $100 million in proceeds from overseas scams through dozens of bank and exchange accounts.
The IRS Criminal Investigation unit and the FBI are handling the case alongside US Attorney Ron Parsons. For investors and compliance professionals, the indictment illustrates the continued federal priority of tracking illicit digital-asset flows across both decentralized networks and traditional banking infrastructure.
