Name

M Subs

Legal name

M Subs Ltd

Website

https://msubs.com

Company type

Private

Founded year

1986

Operating status

Operating

Headcount range

11–50 employees

Ownership category

akta.pro rank

Product category

Submersible Manufacturing

NAICS

Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing (334511), Ship and Boat Building (33661), Ship Building and Repairing (336611)

SIC

Search, Detection, Navagation, Guidance, Aeronautical Sys (3812)

akta.pro primary industry

Unmanned Underwater Vehicles (UUV) & Autonomous Subsea Platforms (IMABAIAF)

akta.pro secondary industries

Manned Submersible & Deep-Sea Research Vehicle Manufacturing (IMAJAOAD), Unmanned Surface Vehicles (USV) & Autonomous Maritime Surface Platforms (IMABAIAE), Unmanned Naval Vessels (USV/UUV) (IMAJABAH), Marine & Underwater Robotics (USVs/UUVs) (HDAAAIAH)

Keywords

• Unmanned underwater vehicles
• Manned submersibles
• Autonomous surface vessels
• Pressure vessel design
• Submersible operations support

Headquarters

HQ city

Lynmouth

HQ country

United Kingdom

HQ region

Europe

Offices3 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

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

Revenue model

1. Manned Submersibles: Design, manufacture and operation of specialized submersibles for military and commercial markets including diver lock-out and dry combat submersibles.
2. Unmanned Underwater Vehicles: UUV and autonomous surface vessel sales for defense and commercial applications including ASW training, mine countermeasures, and surveillance.
3. Engineering & Design Services: Pressure vessel design, control and navigation systems, HP gas and hydraulics, life support systems, GRP tooling, and DC motive power systems.
4. Operations & Support: Worldwide operation of submersibles by expert pilots and engineers, training and qualifying customer personnel on operations and maintenance.

Go-to-market motion1 record

Distribution channels2 records

Marketing channels4 records

Core offering

M Subs designs, manufactures, and operates specialized manned submersibles (diver lock-out and dry combat vehicles) and unmanned underwater vehicles (UUVs) for naval defense and commercial markets. The portfolio also includes autonomous surface vessels (USVs) for over-the-horizon missions, plus engineering design services for pressure vessels and control systems and worldwide submersible operations and training support delivered through sister-company Submergence Group.

Product overview

MSubs is a designer, manufacturer, and operator of both manned and unmanned submersibles for military and commercial markets. The company operates from Plymouth, UK and Roundrock, Texas with sister-company Submergence Group. Their product portfolio includes three main categories: (1) Unmanned Underwater Vehicles (UUVs) including MASTT training target, MORAY multi-role XLUUV, MUST test laboratory, and XLUUV/MANTA/S201; (2) Autonomous Surface Vessels including Oceanus12 and Oceanus17 USVs, and the Mayflower Autonomous Ship with Marine AI; (3) Manned Submersibles including S351 NEMESIS DCS, S302, S303, S361, S401 diver lock-out submarines and the DCS combat submersible. MSubs also provides engineering design services and global operations support.

Differentiator

Problem solved

Functional benefit

Products and services

• MASTT (Mobile Anti-Submarine Training Target) Unmanned underwater vehicle built for US Navy Anti-Submarine Warfare training, threat detection analysis, and torpedo system testing; developed from specification to operational in 13 months.
• MORAY Multi-role XLUUV Multi-role Extra-Large Uncrewed Underwater Vehicle system for sea-denial and maritime domain awareness; modular design configurable for ASW, ASuW, MCM, and ISR roles with networked sensor capabilities.
• MUST (Mobile Under Sea Test Laboratory) UUV developed from a decommissioned Lockheed Martin large-diameter UUV for Anti-Submarine Warfare fleet training and acoustic target services; tow-deployed with autonomous mission execution.
• S201 / XLUUV / MANTA 8.9-tonne Extra-Large Unmanned Underwater Vehicle capable of 48-hour operations at depths up to 305 m; rapid-prototype platform whose hull design is derived from proven manned submersibles and which can be operated manned or unmanned via SUBNAVSYS.
• XV Excalibur XLUUV 12-metre, 19-tonne Extra-Large Uncrewed Underwater Vehicle, the largest XLUUV in the Royal Navy's experimental fleet, developed under Project Cetus with demonstrated 16,000+ km remote operation capability.
• Oceanus12 USV Fully autonomous surface vessel built by Zero USV (M Subs subsidiary) for over-the-horizon operations with ranges up to 3,500 nautical miles; delivered to customers in Canada and the US for hydrographic and intelligence roles.
• Oceanus17 USV Larger 17-metre autonomous surface vessel variant of the Oceanus USV family.
• Mayflower Autonomous Ship AI-powered fully autonomous surface vessel project led by M Subs with MarineAI providing artificial intelligence software; designed for the world's first fully autonomous transatlantic crossing.
• S351 NEMESIS (Dry Combat Submersible) Long-range dry combat submersible with three watertight sections, transport compartment for up to 8 swimmers, and 66 nautical mile range at 5 knots submerged.
• S303 Diver Lock-out Submersible Light diver lock-out class submersible transportable in submarine dry shelters, on submarine decks, or via crane on surface ships; available for approximately £20M.
• S361 Diver Lock-out Submersible Medium payload diver lock-out mini-submarine with long range and endurance; available for approximately £25M.
• S302 Dry Combatant Submersible Dry Combatant Submersible (DCS) swimmer lock-out submersible operating from a submarine or independently, with 2-person crew and payload capacity for 6 swimmers.
• S401 Diver Lock-out Submersible Large payload, long-range, extended-endurance diver lock-out submersible (16 m length, 40-tonne weight) with flexible design that allows trade-off of passengers/payload with additional battery pods; culmination of lessons learned from prior electric, diesel-electric, and diver lock-out submersibles.
• DCS (Dry Combat Submersible) 12-metre dry combat submersible built for US Navy SEALs with 8-passenger capacity, speeds up to 5 knots, and range up to 60 nautical miles.
• Engineering & Design Services Engineering services covering pressure vessel design and construction, control and navigation systems, HP gas and hydraulics, life support systems, GRP tooling, and DC motive power systems.
• Operations & Support Worldwide submersible operations delivered by Submergence Group expert pilots and engineers; provides operational cadre for testing new submersibles and trains/qualifies customer pilots and engineers on submersible operations and maintenance.

Quantifiable outcome

• MASTT developed from specification to operational in 13 months
• +3 more outcomes

Named customers6 records

Segments3 records

Ideal customer profiles3 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration5 records

AI capability1 record

Feature6 records

Partnerships

Six partnerships are on record, tiered minor and core.

• BMTminorStrategic or Co-development Partner · 24 April 2026UK supplier collaboration as part of Teledyne's strategic partnerships to strengthen UK supplier base and meet regional sourcing expectations for UK and European defense programs.
• Teledyne MarinecoreStrategic or Co-development Partner · 27 February 2026Strategic collaboration via MoU signed February 27, 2026 to develop and pursue business opportunities with UK Royal Navy and international naval programs. Integration of advanced maritime technologies including sonars, autonomous systems, and underwater vehicles. Cooperation already underway with Teledyne SeaBat sonars integrated on Zero USV platforms at REPMUS 2025. Planned demonstrations using Slocum gliders and Osprey-class AUVs in UK and Iceland during Q1-Q2 2026.
• Lungteh ShipbuildingminorStrategic or Co-development Partner · 1 January 2025Partnership with Taiwanese shipbuilder Lungteh on a large unmanned underwater vehicle scheduled for completion in 2026, announced at Taipei Aerospace & Defence Technology Exhibition 2025.
• MarineAIcoreStrategic or Co-development PartnerSister company providing artificial intelligence software for the Mayflower Autonomous Ship program and Oceanus autonomous surface vessels. Marine AI provides the AI software while MSubs provides design, engineering and manufacturing.
• Zero USVcoreStrategic or Co-development PartnerZero USV is an MSubs subsidiary developing autonomous surface vessels including the Oceanus series USVs for over-the-horizon operations up to 3,500 nautical miles. Matthew Ratsey is founder and managing director of Zero USV.
• Manor MarineminorImplementation/ SI/ Consulting PartnerHull construction partner for Oceanus17 (17-metre variant of Oceanus USV) at Manor Marine in Portland, with full delivery scheduled for June 2026.

Scale indicators2 records

Recent moves6 records

Expansion highlights6 records

Others

• Teledyne Marine: Teledyne Marine supplies sonars, AUVs (Slocum gliders) and integrated subsea instrumentation to defense and commercial customers. MSubs is now a strategic partner (Feb 2026 MoU) integrating Teledyne sonars on its USVs and is a comparable supplier to the same naval end customers.

Broad incumbents

• Lockheed Martin: Lockheed Martin supplies US Navy submarine and unmanned underwater systems, including prior large-diameter UUVs from which MSubs derived the MUST program. Comparable as a defense prime competing for unmanned maritime and submarine-related defense programs.
• Kongsberg Maritime: Kongsberg Maritime manufactures HUGIN AUVs and a range of USV/autonomous maritime systems for naval and commercial customers. Comparable to MSubs on autonomous underwater and surface vessel technology serving overlapping defense and commercial survey markets.
• Saab: Saab develops autonomous underwater vehicles (Sea Wasp, AUV62) and submarine systems for naval customers globally. Comparable as a defense incumbent offering unmanned maritime products to similar navy buyers, though Saab has a much broader portfolio spanning aircraft, land systems and naval platforms.
• Huntington Ingalls Industries: HII is the largest US military shipbuilder and is expanding into unmanned underwater vehicles and large submersibles. Comparable to MSubs as a defense ship/submersible manufacturer competing for similar US Navy and allied navy procurement budgets.
• L3Harris Technologies: L3Harris develops autonomous surface and underwater maritime systems for defense customers. Comparable as a defense incumbent with overlapping unmanned maritime portfolio addressing similar ASW, MCM and ISR mission sets.
• ThyssenKrupp Marine Systems: TKMS designs and builds submarines (Type 209/212/214) and is developing large unmanned underwater vehicles for European navies. Comparable to MSubs on submersible design and manufacture, though operating at much larger scale and focused on conventional submarines.

Emerging players

• Anduril Industries: Anduril is a US-based defense technology company building autonomous underwater and surface vehicles (e.g., Dive-LD, Bolt) for defense customers. It is comparable to MSubs as an emerging defense tech player bringing capital efficiency and software-defined autonomy to the maritime unmanned market.

Direct peers

• Oceaneering International: Oceaneering designs, manufactures and operates subsea robotic vehicles including ROVs and AUVs for offshore energy, survey and defense customers. Direct peer to MSubs on submersible design, manufacturing, and operations, with similar business model spanning hardware and managed services.

Regional players

• Hanwha Ocean: Hanwha Ocean (formerly DSME) builds submarines and naval vessels primarily for the Republic of Korea Navy and is expanding into unmanned underwater systems. Comparable to MSubs on submarine and large UUV manufacturing for defense customers, though geographically focused on the Korean and Indo-Pacific market.

Market position

Strengths5 records

Weaknesses4 records

Competitive moat5 records

Key risks6 records

Key highlights6 records

Customer concentration

Compliance1 record

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Subsidiaries2 records

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 M Subs