Sioux Falls Crypto Investor Charged with $20M Fraud Scheme

A prominent crypto investor in Sioux Falls has been charged with using eight companies and new investor funds to keep an alleged $20 million fraud alive. Benjamin Paul Wiener, who pleaded not guilty on July 10, is accused of making materially false statements and fraudulent representations to induce people to invest money and digital currency with his companies.

According to the indictment, Wiener moved investor funds through various financial institutions and cryptocurrency exchanges to conceal their location, source, ownership, and control. He allegedly controlled and spent the funds on personal expenses when victim funds became depleted or an investor requested a return of investment.

The government estimates the alleged losses at approximately $20 million across dozens of victims. Wiener used new money for personal expenses and to repay previous investors. The indictment also alleges that Wiener obtained a $1 million line of credit from a Sioux Falls financial institution in April 2025 by falsifying documents, information, and correspondence.

Prosecutors say he used another individual's personal identifying information without authorization to secure the credit. The Justice Department does not identify the bank or the individual whose information was allegedly used. Wiener's trial is scheduled for September 15.