SEC files action against BitConnect, its founder Satish Kumbhani, its top U.S. promoter, and his affiliated company.
BitConnect purportedly raised 325,000 Bitcoin for its Ponzi scheme, worth $2 billion at the time.
The regulator says BitConnect allegedly induced investors to deposit funds for the firm to deploy them in its volatility software trading bot.
The SEC already reached settlements with two of the five individuals charged in a related action for promoting BitConnect and Glenn Arcaro, who pleaded guilty.
The legal action seeks injunctive relief, disgorgement plus interest, and civil penalties.
The defendants are accused of violating the antifraud and registration provisions of the federal securities laws.