The Commodity Futures Trading Commission (CFTC) has charged three decentralized financial services companies (DeFi) – Opyn, Inc., ZeroEx (0x), Inc. and Deridex, Inc. – of illegal derivatives trading, the agency said in a statement released Thursday.

The three companies are accused of using blockchain-based protocols and smart contracts as trading platforms, according to the CFTC. The U.S. derivatives regulator ordered Opyn, ZeroEx and Deridex to cease violations and pay fines of $250,000, $200,000 and $100,000, respectively. The companies agreed to these terms to settle the charges.

But the CFTC may have been particularly familiar with 0x, as it hired an acting director of LabCFTC from 0x Labs.

According to the CFTC, all three companies are accused of illegally offering retail leveraged commodity trades and margin trades using digital assets.

All of these companies, as well as ZeroEx, known for its 0x protocol, cooperated in the investigation, resulting in a reduced financial penalty, according to the CFTC.