A New York-based attorney—representing clients who say they were victimized in a bitcoin-mining scam—said a legal malpractice suit filed in Texas is baseless and meant to derail his clients’ claims.

T. Edward Williams of Williams LLP in New York City was sued in Harris County for legal malpractice by Kaboomracks Inc., RWVK LLC and their owner, Robert Van Kirk. Kaboomracks, a Houston firm that buys and sells bitcoin-mining equipment.