No, Warren Buffett does not own Union Pacific (UNP). In fact, Union Pacific is the primary competitor to the railroad that Buffett does own: BNSF Railway (Burlington Northern Santa Fe). Through his conglomerate, Berkshire Hathaway, Buffett famously acquired BNSF in 2010 in a deal valued at approximately $44 billion, calling it an "all-in wager on the economic future of the United States." While Berkshire Hathaway is a massive investor in the transport sector and has occasionally held small, passive shares in various other railroads for its portfolio, BNSF is a wholly-owned subsidiary and the "crown jewel" of Buffett's rail holdings. Union Pacific remains a publicly-traded company (NYSE: UNP) owned by institutional and individual shareholders. The two railroads dominate the Western United States in a "duopoly," with Union Pacific and BNSF together accounting for the vast majority of freight rail traffic west of the Mississippi River, each operating massive networks of over 30,000 miles of track.