M. A. Mortenson, Jr. A builder of skyscrapers, airports, sports arenas, schools, and manufacturing plants, when he became president of the M. A. Mortenson Company in 1969, it had 15 employees. By 2007, it had 1,200 employees, offices in six states, and annual revenues of $1.4 billion, and it had changed the skylines of dozens of American cities.