The agency rejected several motions to dismiss the proposed merger application of Union Pacific (UP) and Norfolk Southern (NS) before formal review by the Surface Transportation Board (STB).
The decision, issued in a Sept. 18 press release, comes after a series of challenges from rail carriers and shipper-led groups that questioned whether the revised application provides enough evidence to move forward. STB press release, Sept. 18
Several rail carriers and shipper groups filed motions to dismiss the revised application on the grounds that it failed to make a prima facie case on Aug. 18. The legal standard is set to show that there is enough evidence to support a claim. prima facie (Cornell Law School) (filing with STB docket)
CSX Transportation and BNSF Railroad were among the railroads seeking dismissal. Shipper associations including the American Chemistry Council, the American Fuel & Petrochemical Manufacturers and the Alliance for Chemical Distribution also banded together.
The proposed merger has remained under pressure as concerns have been raised over how the combination could change competition across the U.S. freight rail market.
UP and NS announced their intent to merge in June 2025. The proposed combination would create a network of more than 50,000 route miles in 43 states with access to 10 international interchanges and connections to approximately 100 ports.
Industry groups and other stakeholders have raised concerns about whether the deal could harm competition since the deal was announced. Several senators also have warned the STB that the transaction could put pressure on freight rates and service levels, noting that four of the six big U.S. freight rail carriers already control more than 90% of the market.
“ We will continue to make the case to the STB that a healthy freight rail network depends on competition and customer choice, not on increased market concentration and monopoly power,” said the American Chemistry Council.
The STB’s refusal of the latest motions paves the way for the merger application but the agency’s ruling did not deal with the broader competitive concerns surrounding the deal.
Opposing the motions to dismiss, STB board member Richard Kloster said the application lacks sufficient transparency and depth.
“Applicants have submitted thousands of pages of documents, but they don’t present a very robust plan for how they will address competitive concerns or minimize possible harms. They also rely heavily on the benefits to intermodal shipments, a market segment that by today’s standards is already competitive,” Kloster said in the docket filing.
This latest decision also comes after earlier procedural setbacks for UP and NS. The STB rejected the companies’ initial network merger application, filed Dec. 19, 2025, as incomplete and lacking information required under the board’s regulations.
In April 2026, UP and NS submitted a revised application that the agency accepted in May, moving the proposal to the next stage of the regulatory process.
But the STB emphasized its recent decision does not address the merits of the proposed merger and should not be read as a positive endorsement of the transaction. The parties are also at liberty to restate their arguments at the substantive review.
Comments on the merits of the merger are due by Nov. 18; responses to those comments must be filed by Feb. 16, 2027.
