Federal authorities have unveiled charges against ten executives and employees from four cryptocurrency market-making companies in what officials describe as a coordinated international effort to combat deceptive trading practices in the digital asset sector. The indictments, handed down by grand juries in San Francisco and Oakland, target individuals accused of running sophisticated pump-and-dump operations that artificially boosted trading volumes and prices of various cryptocurrencies, ultimately harming investors across the United States and beyond.
The defendants worked for firms including Gotbit, Vortex, Contrarian, and its partner Antier Solutions.
Prosecutors allege the groups employed so-called “wash trading” techniques—coordinated buys and sells that created the illusion of high demand and rising values without genuine market activity.
Once prices were inflated, the perpetrators allegedly sold off their own holdings at peak levels, leaving ordinary buyers with substantial losses.
Among those charged in the Gotbit case, indicted in San Francisco in March 2025, are Taiwanese national Antoine Tsao, the firm’s business development manager, along with Russian sales manager Ian Sofronov and Serbian account manager Nemanja Popov.
All face counts of wire fraud conspiracy and wire fraud.
Tsao was detained at New York’s JFK Airport and later pleaded guilty, receiving his sentence from U.S. District Judge Araceli Martínez-Olguín.
Popov, arrested at San Francisco International Airport, also entered a guilty plea and was sentenced in February 2026.
A separate Oakland indictment from August 2025 names Vortex CEO Gleb Gora, a 24-year-old Russian national, along with chief financial officer Sergei Ryzhkov and business development manager Michael Vogel.
In the third case, filed the following month, Contrarian CEO Manu Singh (Indian national, age 34), chief financial officer Kushagra Srivastava, business development associate Vasu Sharma (Indian national, age 26), and Antier business development manager Sabby Singh stand accused of identical offenses.
Three of the defendants—Gora, Singh, and Sharma—were taken into custody in Singapore in October 2025 following a U.S. request and subsequently extradited.
They made their initial court appearances in Oakland federal court on March 30, 2026, and remain in custody. Each of the ten individuals faces a maximum penalty of 20 years in prison and fines up to $250,000 per count if convicted.
The cases stem from a lengthy undercover investigation led by the FBI, which created its own cryptocurrency tokens to expose the alleged schemes.
IRS Criminal Investigation agents provided crucial support.
More than $1 million in digital assets has been seized as part of the operation. International cooperation proved essential: Singapore authorities, the Justice Department’s Office of International Affairs, and the FBI’s attaché office in Singapore assisted with arrests and extraditions.
The announcement was made jointly by U.S. Attorney Craig H. Missakian for the Northern District of California, FBI Acting Special Agent in Charge Matt Cobo, and IRS-CI Oakland Field Office Special Agent in Charge Linda Nguyen.
Assistant U.S. Attorneys Benjamin K. Kleinman, Daniel M. Pastor, and Molly K. Priedeman are prosecuting the matters.
This action underscores growing U.S. efforts to hold foreign actors accountable for exploiting cryptocurrency markets, signaling to the industry that manipulative practices will face aggressive enforcement regardless of borders. The probe highlights vulnerabilities in decentralized finance and the government’s commitment to protecting retail investors from fraudulent trading tactics.