Europe’s rail data layer is changing hands
Who owns the intelligence beneath Europe’s rail network? Four deals over two years are beginning to answer that question — and the answer matters to everyone who operates or maintains the network.
By Dan Jensen
Siemens Mobility agreed on 14 May to acquire the core businesses of Italian group Mermec — diagnostics, analytics, wayside signalling and data infrastructure — in a deal reportedly worth around EUR 1.2bn according to people familiar with the transaction. It is the latest in a sequence that includes three other deals reshaping the same market over two years:
Vossloh has agreed to acquire British LiDAR specialist Cordel, targeting automated line monitoring on live infrastructure, with completion expected Q3 2026.
Mermec acquired Hitachi Rail’s divested European signalling businesses, closing 31 July 2024, becoming one of Europe’s largest independent signalling players.
Hitachi acquired Thales GTS, closing 31 May 2024, after EU and UK regulators required divestment of Hitachi’s mainline signalling businesses in France, Germany and the UK as a condition of approval.
Four moves, one direction
The sequence begins in 2021, when Hitachi announced its EUR 1.66bn acquisition of Thales Ground Transportation Systems — a deal that took three years and clearance from 13 competition authorities to close. The European Commission and UK’s Competition and Markets Authority approved it in October 2023, but only on one condition: Hitachi had to sell its existing mainline signalling businesses in France, Germany and the UK.
The buyer was Mermec, an Italian rail technology group founded in 1970 and owned by Angelo Holding. The deal closed 31 July 2024, transferring around 550 employees and establishing new subsidiaries to manage the acquired operations: Compagnie des Signaux in France and Mermec Deutschland for Germany, Austria and Switzerland.
Mermec entered the transaction as a specialist in diagnostics and measurement technology. It emerged as one of Europe’s largest independent signalling players.
In May 2026, Siemens agreed to acquire Mermec’s core diagnostics, analytics and data infrastructure businesses. Those signalling subsidiaries — Compagnie des Signaux, Mermec Deutschland and Angelstar — are not part of the deal. They remain with Angelo Holding and will continue as independent signalling businesses under the Angel Signaling name, with around 800 employees and an order backlog of approximately EUR 2bn.
A day before the Siemens announcement, Vossloh — primarily a track hardware supplier of rails and switches — agreed to acquire British LiDAR specialist Cordel Group, targeting automated condition monitoring on live infrastructure.
Data as the product
What these transactions have in common is not signalling. It is the capacity to measure, analyse and operationalise infrastructure data at scale — in practice, the systems that record network condition, store years of degradation history and turn those patterns into maintenance decisions.
Siemens after closing would hold a vertical stack with few precedents in the rail technology market. The acquired Mermec businesses serve customers in more than 70 countries, generating continuous condition data on track geometry, overhead line status and structural integrity.
Combined with Siemens’ existing onboard and depot-based diagnostics, the result would be a platform covering the full cycle: data generated on the network, processed in the depot, analysed at the system level.
Siemens estimates revenue synergies from the combined platform at more than EUR 400m annually in the medium term, rising to EUR 500m in the long term. Those are the numbers of a structural repositioning, not a bolt-on.
Tells a parallel story
Vossloh’s move tells a parallel story. A company whose core business is manufacturing rails, switches and rail fastening systems has agreed to acquire a specialist in LiDAR-based automated line inspection. The physical layer and the data layer, under one roof.
The signalling market was already highly concentrated before any of these transactions. Siemens, Alstom and Hitachi-Thales hold the dominant positions on ETCS and mainline signalling infrastructure across Europe. The EU’s remedy in the Hitachi/Thales case was explicitly designed to create a viable fourth player — a counterweight to further concentration.
Those signalling businesses remain independent under Angelo Holding. What Siemens has chosen to acquire is something different: the diagnostics and data infrastructure that sits alongside signalling, and that is now moving into fewer hands.
What it means for operators and infrastructure managers
The practical consequence is a procurement question. When contracting diagnostics and condition monitoring services, the terms governing data ownership, portability, third-party access and exit rights matter as much as the service specification. In a more concentrated supplier market, the leverage to negotiate those terms decreases.
The switching cost in diagnostics is not the hardware. It is the data history. A train can be replaced at the end of a contract cycle. The diagnostics system that has spent years building a condition baseline for a specific network — tracking degradation curves, calibrating maintenance intervals, accumulating comparative data — is not easily swapped.
Infrastructure managers generate condition data through their own measurement operations. But the processing, the analytics platform, the algorithms that turn raw measurement into maintenance recommendations — those increasingly sit with the supplier. Who owns the output is not always the same question as who owns the infrastructure.
For anyone working on bids, projects and delivery in European rail, the market for independent diagnostics and monitoring capability is materially narrower than it was two years ago. The contracts being signed now will determine how much leverage remains in the next cycle.
Who is asking the question
The EU spent significant political capital ensuring competition in rail signalling. The Hitachi/Thales remedies worked as designed: the divested businesses continue as Angel Signaling, an independent player with a EUR 2bn order backlog. European regulators demonstrated they understood the stakes and were prepared to act.
The diagnostics and infrastructure data segment is a different question. The Siemens/Mermec and Vossloh/Cordel transactions are subject to regulatory approvals; no structural remedies have been announced to date.
Whether that changes depends on how regulators define the relevant market — and whether the convergence of diagnostics, condition monitoring and asset analytics into integrated supplier platforms registers as a competition concern or simply as industrial consolidation.