In Ruiz v. Chwatt Assocs. (NYLJ, Aug. 20, 1997, at 21, col 4), an action in Supreme Court, New York County, for an alleged rent overcharge, involving a professional apartment on the ground floor of a large cooperative apartment building rented to a doctor, a residential lease was used, with a rider that restricted use to a medical office. The court concluded that the doctor was not given permission to move a bed in and live in what had been, for the former doctor tenant, an operating room, while using the rest as a medical office.