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.