Jeffer Mangels Butler & Mitchell LLP | 3,601 followers on LinkedIn. Jeffer Mangels Butler & Mitchell LLP (JMBM) is a full service law firm of approximately 120 lawyers. From its offices in Los Angeles, San Francisco and Orange County, it serves its clients'​ needs worldwide. The firm's lawyers provide counseling and litigation services in a wide range of areas including environment, land use and energy, intellectual property, labor and employment, corporate, bankruptcy, entertainment, real estate, tax and trusts & estates.