The merger would create the United States’ first coast-to-coast rail network, spanning 50,000 miles and 43 states.

The proposed merger, announced Tuesday, would marry Union Pacific’s vast rail network in the West with Norfolk’s rails that snake across 22 Eastern states, and the District of Columbia.

Antitrust regulators have approved over 100 mergers so far in 2025. However, according to a recent report from Semafor, the ...