MDU Resources Group

Founded in 1924, MDU Resources Group engages in regulated energy delivery, and construction materials and services businesses in the United States. It operates through five segments: Electric, Natural Gas Distribution, Pipeline and Midstream, Construction Materials and Contracting, and Construction Services. It also offers utility excavation, and mechanical piping and services; and manufactures and distributes transmission line construction equipment and other supplies. The company is headquartered in Bismarck, North Dakota.