Douglas Elliman is suing venture capital-backed brokerage Compass and its president Leonard Steinberg for an alleged “unlawful scheme” to steal its brokers and interfere with its exclusive contracts. Elliman, headed by Howard Lorber and Dottie Herman, has accused Steinberg and his colleague Herve Senequier, both former Elliman agents, of breaching non-solicit agreements by raiding the company’s talent pool, according to the complaint filed Monday in New York State Supreme Court.