Coinbase is facing a new lawsuit alleging that its employees and other insiders reaped huge gains by trading on nonpublic information that the cryptocurrency exchange planned to support transactions in a Bitcoin offshoot called Bitcoin Cash.

The class action suit, filed Thursday in the U.S. District Court for the Northern District of California, appears to be the first filed in a federal court alleging insider trading-like claims over Coinbase’s announcement that it would handle transactions in Bitcoin Cash last December.