In 2001, the company acquired Litton Industries, a shipbuilder and defense electronics systems provider for the U.S. Navy. During the acquisition process, a new Delaware holding company, NNG, Inc., was formed, which merged with Northrop Grumman through a one-for-one common shares exchange in April 2001. Both Northrop Grumman and Litton became subsidiaries of the new holding company. The original Northrop Grumman Corporation then changed its name to "Northrop Grumman Systems Corporation"; the holding company, NNG, Inc., changed its name to "Northrop Grumman Corporation". Later that year, Newport News Shipbuilding was added.