NSC merger would significantly expand Union Pacific's rail network, potentially challenging the dominance of BNSF Railway, which Berkshire Hathaway acquired in

Union Pacific and Norfolk Southern are in merger talks to create the largest railroad in North America that would connect the East and West Coasts.

Union Pacific , the largest U.S. freight railroad operator, is exploring a possible acquisition of Norfolk Southern to create a $200 billion coast-to-coast rail network, a person familiar with the matter said.