What Siepel does

Siepel is a French electromagnetic engineering company founded in 1986, operating since September 2021 as a Business Unit of Cegelec Défense (Vinci Energies Group). The company designs and manufactures two integrated product families at its 10,000 m² production site in La Trinité-sur-Mer (Brittany): (1) electromagnetic test equipment, including anechoic chambers (HERA, HERMES, ARES, CHRONOS, ATHENA series), reverberation chambers (EOLE series), Faraday cages, modular shielded rooms, and a complete SEA absorber product line (pyramidal, hybrid, ferrite, metamaterial, weatherproof, walkway types) covering 30 MHz to 110 GHz with power handling up to 15 kW/m²; and (2) infrastructure cybersecurity products, including SOTERIA secure conference rooms, Secure Box mobile enclosures, shielded racks, mini shielded rooms, and shielded pouches designed to counter TEMPEST, IEMI, and acoustic interception threats.

The company's core technology rests on proprietary electromagnetic absorption (LIV coating, polyurethane foam impregnated with carbon, ferrite tiles, honeycomb) and shielding (SIE-xD doors using brass knife and beryllium bronze contacts, power and signal line filters 14 kHz–40 GHz) combined with proprietary installation methods (Ferrite Smart Rail with 25-year mechanical warranty). Siepel Measurements, an ISO/IEC 17025 COFRAC-accredited entity (No. 1-7068), is the only anechoic chamber manufacturer worldwide with this accreditation, providing independent performance verification (shielding effectiveness, quiet zone, NSA, FU measurements) for all chamber brands.

Siepel operates a direct B2B enterprise sales model managed by dedicated Business Managers and Project Managers, with all design, manufacturing, installation, and measurement done in-house at La Trinité-sur-Mer. Revenue streams combine one-time capital-equipment sales (catalog chambers, absorbers, shielded enclosures), professional services (installation, commissioning, accredited measurement), and recurring maintenance contracts (MCO, spare parts, training). The customer base spans French and international government/defence (French Ministry of Defence since 1999, embassies since 1986), aeronautics/aerospace (satellite, missile, fighter aircraft testing per DO 160, MIL STD 461), telecommunications (5G, satellite, IoT), automotive EMC, and academic/research institutions, with installed references in France, Turkey, Singapore, Denmark, UK, South Korea, Tunisia, and Africa.

Name

Siepel

Legal name

Siepel

Website

https://siepel.com

Company type

Private

Founded year

1986

Operating status

Operating

Headcount range

101–250 employees

Short description

Siepel is a French manufacturer of electromagnetic test equipment (anechoic/reverberation chambers, absorbers, Faraday cages) and infrastructure cybersecurity products (shielded rooms, secure conference rooms, mobile enclosures), serving defence, aerospace, telecom, automotive, and government clients worldwide.

Ownership category

akta.pro rank

Product category

Electromagnetic Test Equipment

NAICS

Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals (334515), Testing Laboratories and Services (541380), Navigational, Measuring, Electromedical, and Control Instruments Manufacturing (33451)

SIC

Instruments For Meas & Testing Of Electricity & Elec Signals (3825), Services-Testing Laboratories (8734), Measuring & Controlling Devices, Nec (3829), Industrial Instruments For Measurement, Display, And Control (3823)

akta.pro primary industry

Third-Party Certification, Code Compliance & Regulatory Inspection (ASME/API/ISO) (EUAEAHAN)

Keywords

• Electromagnetic shielding
• Anechoic chambers
• EMC testing equipment
• Electromagnetic absorbers
• Faraday cages

Headquarters

HQ city

La Trinité-sur-mer

HQ country

France

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

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

Revenue model

1. Electromagnetic test equipment sales: Design, manufacture and sale of anechoic chambers (EMC and antenna measurement), reverberation chambers, Faraday cages, shielded rooms, electromagnetic absorbers (SEA product lines), shielded doors, filters, and honeycomb vents. Equipment sold as custom or standard catalogue products with optional turnkey integration including third-party instrumentation.
2. Installation and commissioning services: On-site installation of anechoic chambers, shielded rooms, and associated equipment. Includes supervision by dedicated project manager, logistics management worldwide, and integration of test instrumentation for turnkey projects.
3. Measurement and testing services (Siepel Measurements): Independent ISO 17025 accredited measurement entity providing performance verification of anechoic chambers and shielded rooms. Services include shielding effectiveness, site attenuation, field uniformity, and quiet zone measurements. Operates in France and internationally for all brands of chambers.
4. Maintenance and operational support (MCO): Preventive and corrective maintenance services for all types of Faraday cages, anechoic chambers, and shielded boxes. Includes spare parts supply, first-level maintenance training, and ongoing support. Quote-based engagement model.
5. Cybersecurity and data protection solutions: Sale of mobile security products (shielded pouches, secure boxes), secure conference rooms (SOTERIA), shielded racks, and mini shielded rooms for anti-eavesdropping and data protection applications.

Pricing tiers

Go-to-market motion2 records

Distribution channels3 records

Marketing channels4 records

Core offering

Siepel designs, manufactures, and installs electromagnetic test and protection solutions for industrial, defense, and research clients. Its core offerings include anechoic chambers (SEA series), shielded rooms (Faraday cages), pyramidal electromagnetic absorbers, RF access control doors, and cybersecurity shielding solutions. The company serves as a vertically integrated manufacturer and integrator of high-technology electromagnetic shielding systems.

Product overview

Siepel is a French company (Business Unit of Cegelec Défense, Vinci Energies Group) specializing in electromagnetic testing and protection solutions. The company offers two main product domains: (1) Test Means including EMC and antenna measurement chambers (Anechoic Chambers, Reverberation Chambers, EMC Absorbers, Microwave Absorbers), and (2) Data Security including infrastructure cybersecurity products (Shielded Rooms, Secure Conference Rooms, Shielded Racks, Mini Shielded Boxes) and mobile cybersecurity (Shielded Pouches, Secure Box). The product portfolio includes standardized chamber models (HERA, HERMES, ARES, CHRONOS, ATHENA, EOLE series), proprietary absorber lines (SEA-PM, SEA-HP, SEA-MP, SEA-WM, SEA-WW, SEA-MLM, SEA-F, SEA-WP, SEA-CM, SEA-META, SEA-FE, SEA-HY, SEA-HYT), shielded room components (doors, filters, honeycomb vents), and associated measurement/maintenance services through Siepel Measurements (ISO 17025 accredited). The company designs, manufactures, and installs all products at its 10,000 m² production facility with 60+ employees.

Differentiator

Problem solved

Functional benefit

Brands

• Siepel Measurements: ISO17025 accredited measurement entity providing shielding efficiency measurements, quiet zone measurements, NSA measurements, and material characterization services.
• SOTERIA
• Secure Box

Products and services

• SEA Anechoic Chambers
• SEA Pyramidal Absorbers
• Shielded Rooms / Faraday Cages
• RF Shielded Doors and Access Control
• Cybersecurity Shielding Solutions

Quantifiable outcome

• Electromagnetic attenuation values exceeding 100 dB (10 MHz to 10 GHz) for shielded racks
• +4 more outcomes

Named customers5 records

Segments5 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature10 records

Partnerships

Two partnerships are on record, tiered major and core.

• IETR (Institut d'Electronique et des Technologies du numéRique), University of Rennes 1majorStrategic or Co-development Partner · 22 September 2021Siepel delivered three anechoic chambers (CACENDRA, CAMILL, DIADEM) for IETR's new research hall at University of Rennes 1. Siepel handled faradisation (shielding) of spaces 15m x 6m x 6m and 14m x 4m x 4m, and installed approximately 5,000 absorber blocks. Contract notified in March 2021, completed September 2022. Project showcased Siepel's ability to deliver unique, complex research infrastructure.
• Cegelec Défense Mechatronics Solutions (CDMS), Clermont-FerrandcoreStrategic or Co-development PartnerTwo entities of Cegelec Défense worked jointly on the IETR project. Siepel handled faradisation and absorbers while CDMS supplied large-dimension spherical positioning systems and vertical scanners covered with Siepel absorbers. The partnership was facilitated by shared belonging to Cegelec Défense group.

Scale indicators10 records

Recent moves7 records

Expansion highlights5 records

Direct peers

• ETS-Lindgren: ETS-Lindgren is the largest global manufacturer of anechoic and reverberation chambers, EMC absorbers, and shielded rooms. Directly competes with Siepel across virtually the entire HERA/HERMES/EOLE product portfolio for the same aerospace, defense, automotive, and wireless customers.
• Albatross Projects: Germany-based Albatross Projects is a turnkey EMC/RF testing facility builder specializing in chambers and absorbers. Competes with Siepel on the same aerospace, automotive, and defense tenders, particularly in the German-speaking European market.
• TDK RF Solutions: TDK RF Solutions (formerly EPCOS) manufactures EMC/RF absorbers and components, including ferrite tiles and pyramidal foam absorbers that compete head-to-head with Siepel's SEA-FE, SEA-PM, and SEA-HY product lines used in anechoic chambers.
• Microwave Vision Group (MVG): MVG designs antenna measurement systems and anechoic chambers for telecommunications, aerospace, and defense. Competes with Siepel in antenna measurement chambers and RCS testing infrastructure for satellite, 5G, and defense applications.
• Holland Shielding Systems: Holland Shielding Systems manufactures EMI/RFI shielding products including Faraday cages, shielded doors, and conductive gaskets. Directly comparable to Siepel's shielding portfolio (shielded rooms, SIE-xD doors) for data centers, medical, and government applications.
• Frankonia Group: Frankonia is a German provider of EMC test solutions including anechoic chambers, GTEM cells, and reverberation chambers. Directly competes with Siepel's EOLE reverberation chambers and HERA series for automotive and industrial EMC compliance testing.

Broad incumbents

• Rohde & Schwarz: Rohde & Schwarz is a broad incumbent in test & measurement that also offers shielded chambers, EMC test systems, and antennas as part of its wider instrumentation portfolio. Overlaps with Siepel on integrated turnkey EMC test facilities where R&S provides instrumentation.
• Keysight Technologies: Keysight is a major electronic measurement incumbent that supplies EMC test instrumentation and software paired with chamber installations. Adjacent competitor in end-to-end EMC test solutions where Keysight bundles its instruments with third-party chambers in Siepel's space.

Emerging players

• Comtest Engineering: Comtest Engineering is a Spanish EMC test solutions provider offering reverberation chambers and EMC consulting services. Comparable to Siepel's EOLE reverberation chambers and Siepel Measurements services for smaller European EMC testing customers.
• Aaronia AG: Aaronia AG offers RF shielding solutions, TEMPEST/TSCM products, and measurement chambers. Overlaps with Siepel on cybersecurity/anti-eavesdropping products (shielded pouches, Secure Box-like offerings) for government and high-security customers.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights6 records

Customer concentration

• LinkedInfr.linkedin.com/company/siepel

Compliance6 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Subsidiaries1 record

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 Siepel