Seli Overseas

What Seli Overseas does

Seli Overseas S.p.A. is an Italian specialist civil engineering contractor focused exclusively on mechanized tunnel excavation using Tunnel Boring Machines (TBMs). Founded in Rome in 1950 by engineer Carlo Grandori and integrated into the Webuild Group in 2021 (after a 2018 acquisition by Salini Impregilo), the company operates across railways, roads, metros, sewers, aqueducts, and hydroelectric infrastructure, with a cumulative track record of 846 km of tunnels delivered across 32 countries on five continents. Its technology portfolio spans multiple TBM architectures — EPB (Earth Pressure Balance), Slurry/Mix-shield, Double Shield, Dual Mode, Multi Mode, TBM Compact, Telescopic Double Shield Universal, and Continuous Mining — supported by proprietary features including separated-spaces backup systems, real-time geoelectrical ahead-of-TBM geological detection, and Green TBM drives with high-efficiency PMSM motors.

The business model is project-based B2G contracting: Seli Overseas acts as a specialist subcontractor within consortiums and joint ventures led by large general contractors (primarily Webuild) and tenders for fixed-price or cost-plus contracts awarded by public infrastructure owners such as RFI (Italy), CNAIR SA (Romania), EMA (Algeria), and Petrojet (Egypt). Revenue is earned over the construction duration of each tunnel project, with no consumer-facing distribution and pricing determined through competitive public procurement rather than published price lists. Approximately 900 employees as of 2025/2026 support concurrent execution of mega-projects including the Terzo Valico dei Giovi, Salerno-Reggio Calabria and Messina-Catania high-speed railways in Italy, the Sibiu-Pitesti Motorway Lot 3 in Romania, the Lodz Railway Node in Poland, and Cairo Metro Line 4 in Egypt. The company is differentiated by 75 years of accumulated tunneling expertise spanning three generations of engineers, pioneering development of double-shield TBM technology in the 1970s, and a comprehensive certification stack (ISO 9001/14001/45001/37001, SA 8000, UNI PdR 125) that qualifies it for European public infrastructure tenders.

Name

Seli Overseas

Legal name

Seli Overseas S.p.A.

Website

https://selioverseas.com

Company type

Private

Founded year

1950

Operating status

Operating

Headcount range

51–100 employees

Short description

Seli Overseas is an Italian specialist civil engineering contractor and Webuild Group subsidiary that delivers mechanized tunnel excavation services using multiple TBM technologies (EPB, Double Shield, Dual Mode, Multi Mode, Slurry) for government rail, road, metro, sewer, aqueduct, and hydroelectric infrastructure projects globally.

Ownership category

akta.pro rank

Product category

Tunnel Construction Services

SIC

Water, Sewer, Pipeline, Comm & Power Line Construction (1623)

akta.pro primary industry

Tunnel Construction (Road, Rail, Utility) (IMAFAEAC)

Keywords

• Mechanized tunnel excavation
• Tunnel boring services
• Underground infrastructure construction
• TBM civil engineering
• Subway railway tunneling

Headquarters

HQ city

Rome

HQ country

Italy

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Supply Chain, Technology or R&D, Infrastructure, Marketing or Sales

Revenue model

1. Infrastructure Construction Contracts: SELI Overseas generates revenue through fixed-price or cost-plus contracts as a specialist subcontractor or joint venture partner on large civil infrastructure projects involving mechanized tunnel excavation. Revenue is project-based, earned over the duration of construction contracts. The company operates as part of consortiums and joint ventures on major railway, metro, road, and hydroelectric projects.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels6 records

Core offering

Seli Overseas is the Webuild Group company specializing in underground works and mechanized TBM tunnel excavation for the construction of subways, railways, sewer aqueducts, and hydroelectric plants. The company provides specialist subcontracting and joint-venture tunneling services across railway, road, sewer, urban metro, aqueduct, and hydroelectric infrastructure projects in 32 countries using EPB, Dual Mode, Mix-shield/slurry, Double Shield, and Continuous Mining TBM technologies.

Product overview

SELI Overseas is a construction company specializing in underground works and mechanized tunnel excavation with TBMs. As part of the Webuild Group, it offers a comprehensive suite of tunnel boring services utilizing multiple TBM technologies (EPB, Dual Mode, Mix-shield/slurry, Double Shield, and Continuous Mining systems) across infrastructure sectors including railways, roads, sewers, underground transit, aqueducts, and hydroelectric plants. The company has excavated over 846 km of tunnels in 32 countries over 75 years of operation.

Differentiator

Problem solved

Functional benefit

Products and services

• Mechanized Tunnel Excavation Services Specialized subcontracted mechanized tunnel excavation services using Tunnel Boring Machines (TBMs), including EPB, Dual Mode, Mix-shield/slurry, Double Shield, and Continuous Mining technologies, for infrastructure projects across railways, roads, sewers, underground transit, aqueducts, and hydroelectric applications. Awarded via competitive tendering to government infrastructure authorities (e.g., RFI, CNAIR SA) and general contractor consortiums led by firms such as Webuild.
• EPB TBM Tunnel Excavation Earth Pressure Balance Tunnel Boring Machine excavation service used in soft ground conditions, including alluvial deposits below the water table, balancing terrain pressure during advancement for maximum front stability and operational safety. Used in projects such as Lodz Railway Node (Poland), Radimero tunnel (Italy), Lonato tunnel (Italy), Poiana Tunnel (Romania), and Algiers Metro extension.
• Double Shield TBM Tunnel Excavation Double shield tunnel boring machine service with telescopic capabilities designed for hard rock conditions, featuring conical shields and advanced ground pre-treatment systems for challenging clay and squeezing ground conditions. Used in projects such as Terzo Valico dei Giovi, Tel Aviv-Jerusalem railway Line C, Kishanganga (India).
• Dual Mode TBM Tunnel Excavation Dual Mode Tunnel Boring Machine service capable of adapting operating parameters to varying geological conditions along the tunnel alignment, switching between modes as needed. Used in projects such as Fortezza-Ponte Gardena railway quadrupling and Beles Headrace (Ethiopia).
• Mix-shield/Slurry TBM Tunnel Excavation Mix-shield/slurry type TBM excavation service used in sandy and silt geological formations, featuring slurry support systems for face stability. Used in projects such as Cairo Metro Line 4 and Bergen Point outfall tunnel (USA).
• Continuous Mining Tunnel Excavation Green technology tunnel excavation service using a cyclic conventional advancement and segment lining ring assembly process that improves operational efficiency while significantly reducing energy consumption and environmental impact during excavation.
• TBM Compact Tunnel Excavation (Mining Tunnels) Specialized compact TBM excavation service developed for unlined tunnel mining applications, versatile and suitable for mining tunnels. Used in the Los Bronces copper mine expansion in Chile (7.6 km tunnel, completed 2010).
• Ground Freezing Shaft Excavation for Underwater Tunnels Ground freezing technology service used to stabilize soil during shaft excavation for underwater tunnel projects, combined with slurry TBM capable of pipe jacking mode and segment lining. Awarded Best Infrastructure Construction Site in the USA (2021) for the Bergen Point Water Treatment System Outfall Tunnel project.
• Asbestos-Affected Ground Tunnel Excavation Specialized tunnel excavation service in asbestos-containing ground, with dedicated equipment, containment, bagging, and specialized disposal systems. Used in the Radimero tunnel (7.5+7.5 km twin tubes) on the Terzo Valico dei Giovi project.
• Real-Time Geoelectrical Ahead-of-TBM Investigation Innovative geophysical survey service implemented during mechanized TBM advance for real-time detection of geological formations ahead of the TBM, deployed on the Doha Gold Line project.
• TBM Tunneling Technical Consultancy and Personnel Supply Technical consultancy and key personnel supply for mechanized tunnel excavation projects on EPB TBMs in alluvial ground under water table, provided to other tunnel contractors such as PBDiM for the Lodz Railway Node project in Poland.

Quantifiable outcome

• 846 km of tunnels excavated in 32 countries across 5 continents
• +6 more outcomes

Named customers13 records

Segments6 records

Ideal customer profiles3 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature12 records

Scale indicators5 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Ghella SpA: Italian civil engineering contractor specializing in underground works and mechanized tunneling. Direct competitor and frequent consortium partner with Seli Overseas and Webuild on Italian high-speed rail projects such as Terzo Valico and AV Salerno-Reggio Calabria.
• Implenia AG: Swiss construction group with a major tunneling division executing complex underground works across Europe. JV partner with Webuild/Seli Overseas on the Fortezza-Ponte Gardena quadrupling and competes for similar Alpine and metro tunneling tenders.

Broad incumbents

• Vinci Construction Grands Projets: Large French construction contractor with significant tunneling capabilities, executing major metro and rail tunnel projects globally. Operates a much broader portfolio but competes for the same large-scale underground infrastructure tenders as Seli Overseas.
• Bouygues Construction: Major French construction group executing complex underground works including metro and rail tunnels across Europe, Middle East, and Asia. Competes with Seli Overseas on large infrastructure tenders and is part of the broader competitive set.
• Strabag AG: Austrian construction group with a substantial tunneling division executing metro and rail tunnels across Europe. Competes with Seli Overseas for major underground infrastructure projects, particularly in Central Europe and Alpine regions.
• Skanska AB: Swedish construction group with significant tunneling and underground infrastructure capabilities, executing metro, rail, and road tunnel projects across the Nordics, UK, and North America. Comparable scale and project-type exposure to Seli Overseas.
• Acciona Infraestructuras: Spanish construction group executing large tunnel and underground infrastructure projects, including rail and metro work. Competes with Seli Overseas in European and Latin American tenders.

Emerging players

• China Railway Construction Corporation (CRCC): Chinese state-owned construction conglomerate with extensive tunneling capabilities and growing international presence through Belt and Road projects. Increasingly competes for major rail and metro tunneling tenders in Asia, Africa, and Middle East.

Regional players

• Taisei Corporation: Japanese construction major with strong tunneling and underground engineering capabilities, primarily active in Japan and select Asian markets. Comparable in technical expertise for complex geology but operates in a different primary geography.

Others

• Herrenknecht AG: World-leading manufacturer of TBMs and supplier of tunneling equipment to contractors including Seli Overseas. Not a direct contractor competitor but a critical technology enabler whose equipment portfolio and proprietary TBM designs shape the competitive landscape in which Seli Overseas operates.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat5 records

Key risks5 records

Key highlights6 records

Customer concentration

• LinkedInlinkedin.com/company/seli-overseas-s.p.a.

Compliance6 records

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Seli Overseas