STB Resumes Review of $85B Union Pacific–Norfolk Southern Merger, Timeline Extended into Mid‑2027

STB Resumes Review of $85B Union Pacific–Norfolk Southern Merger, Timeline Extended into Mid‑2027

Wed, September 23, 2026

The U.S. Surface Transportation Board (STB) has officially resumed its review of the proposed $85 billion merger between Union Pacific and Norfolk Southern (NYSE: NSC), ending a temporary pause and prescribing a detailed timeline that now extends into late spring of 2027.

Merger Review Resumes; No Endorsement Implied

On August 18, 2026, the STB announced it had removed the proceeding from abeyance, signaling the formal resumption of its review of the proposed merger, which would unite two of the nation’s largest freight railroads into the first coast‑to‑coast rail network. Importantly, regulators emphasized that this procedural step does not indicate approval of the merger proposal. These developments were reported by Reuters and confirm the move forward in review without any material judgments concluded.

The board’s action also required Union Pacific and Norfolk Southern to resubmit any previously “filtered or screened” workpapers, ensuring transparency in regulatory analysis. The deadline for submitting these unfiltered documents was set for August 28, reflecting the board’s insistence on full disclosure.

Extended Procedural Timeline Through Mid‑2027

Regulatory documents—confirmed via coverage from WOWT—outline a more drawn‑out timetable for the review process. The STB has set several key deadlines:

  • Submission of additional data omitted in earlier filings was mandated by August 28.
  • Stakeholders wishing to participate were required to file notice by September 4.
  • Preliminary comments from the Department of Justice (DOJ) and Department of Transportation (DOT) were due by December 3.
  • Responses to those comments and any filed protests were due by February 16, 2027.
  • Public hearings are expected to occur after March 29, 2027, with the final procedural stages—including possible evidentiary submissions—extending into late May 2027.

This extended schedule reflects the STB’s determination that the proposed merger’s scale and consolidation impact warrant a thorough, deliberate review process.

Implications for Norfolk Southern

The resumption and extension of the review process introduces a longer period of regulatory uncertainty for Norfolk Southern. While this maintains the integration timeline open through mid‑2027, it also delays any potential benefits from merger synergies, including streamlined service offerings and cost efficiencies.

This ongoing procedural oversight could weigh on investor sentiment, as the prolonged timeline and the requirement for full disclosure heighten scrutiny and complicate planning on both operational and strategic fronts.

Key Takeaways

  • The merger review is officially underway again, but approval remains far from certain.
  • The STB’s detailed procedural schedule stretches the process into late May 2027.
  • Norfolk Southern faces continued regulatory uncertainty, with implications for investor outlook and strategic execution.