Sonoma County investors Ken Mattson, Tim LeFever and their shared corporations were served a federal class-action lawsuit by three firms based in San Francisco and San Diego. The lawsuits are on behalf of their investors. The complaint accuses Mattson and LeFever of fraud through a real estate scheme. Mattson and LeFever were lifelong friends, but their partnership severed in April when LeFever alerted investors that he had replaced Mattson as CEO of LeFever Mattson Inc.