MDU Construction Services Group, Inc.
MDU Construction Services Group provides electrical and mechanical and transmission and distribution specialty contracting services. It serves customers in the utility, manufacturing, transportation, commercial, industrial, institutional, renewable and government markets.
MDU Resources Group, Inc.
Founded in 1924, MDU Resources Group provides essential products and services through two lines of business: regulated energy delivery and construction materials and services. The company has been traded on the New York Stock Exchange since 1948 under the symbol MDU.