The combination of two large rail companies would create the first coast-to-coast network, but the deal could reduce competition.

Union Pacific (UNP) upgraded by Jefferies amid merger talks with Norfolk Southern (NSC). Explore how this deal could reshape the U.S. rail industry.

Railroad operator Union Pacific is exploring a deal to buy smaller rival Norfolk Southern , the Wall Street Journal reported, in a merger that would bolster the industry leader's heft and likely draw intense regulatory scrutiny.