# Top 30 companies with in-house R&D in the Seine-Maritime department
Tamtam tracks 67 companies with in-house R&D headquartered in the Seine-Maritime department. This list ranks the 30 largest by number of employees on LinkedIn, led by Sidel, CHU de Rouen and Novacel. Their median headcount is 119. Half of them were founded in 1985 or later. The most common headquarters are Rouen (4), Le Havre (3) and Saint-脡tienne-du-Rouvray (2).
The Seine-Maritime department hosts a mix of established companies and institutions with a focus on in-house research and development. This includes large entities like Sidel, which provides packaging equipment, and CHU de Rouen, a major hospital network. Mid-sized firms such as Novacel, specializing in protective films, and Alpha Maintenance, offering engineering services for the oil and energy sector, also feature.
The data shows a diverse industrial base. For example, Groupe Nutriset and Nexira are active in food and beverage manufacturing, with the former focused on nutritional products and the latter on natural ingredients. ESIGELEC is a higher education institution, while SOGET provides IT services for port community systems, indicating a blend of manufacturing, healthcare, education, and technology sectors.
馃嚝馃嚪 Seine-Maritime 路 30 companies 路 Updated Nov 13, 2026
| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [Sidel](https://www.tamtam.ai/c/sidel) (sidel.com)
Provides equipment, services for packaging beverages, food, home and personal care products in various materials, focusing on customer needs and performance. | Machinery Manufacturing | 馃嚝馃嚪 Octeville-sur-Mer | 6,370 | 1965 |
| 2 | [CHU de Rouen](https://www.tamtam.ai/c/chu-de-rouen) (chu-rouen.fr)
Large hospital network providing patient care, medical education, and research, supporting regional healthcare and training future health professionals. | Hospitals and Health Care | 馃嚝馃嚪 Rouen | 3,823 | |
| 3 | [Novacel](https://www.tamtam.ai/c/novacel) (novacel-solutions.com)
Provides technical films, tapes, papers, and machines to protect and preserve material surfaces across various industrial market segments. | International Trade and Development | 馃嚝馃嚪 D茅ville-l猫s-Rouen | 390 | |
| 4 | [ESIGELEC : 脡COLE D'ING脡NIEURS-ES G脡N脡RALISTES](https://www.tamtam.ai/c/esigelec-ecole-d-ingenieurs-es-generalistes) (esigelec.fr)
Specializing in general engineering education, the company offers various programs in Intelligent and Connected Systems, emphasizing project-based learning, internships, entrepreneurship, and innovation for over 10,000 graduates | Higher Education | 馃嚝馃嚪 Saint-脡tienne-du-Rouvray | 341 | |
| 5 | [Alpha Maintenance](https://www.tamtam.ai/c/alpha-maintenance) (alpha.fr)
Company specializing in oil and energy sector, providing services and solutions based in Port-de-Bouc, France. | Engineering Services | 馃嚝馃嚪 Rouen | 333 | 1986 |
| 6 | [Groupe Nutriset](https://www.tamtam.ai/c/groupe-nutriset) (groupenutriset.fr)
Research, production, and distribution of nutritional products to treat and prevent malnutrition among vulnerable populations worldwide. | Food and Beverage Manufacturing | 馃嚝馃嚪 Malaunay | 246 | 1986 |
| 7 | [Les Ateliers du Go没t](https://www.tamtam.ai/c/les-ateliers-du-gout) (les-ateliers-du-gout.fr)
Production of homemade-style French recipes for professional restaurateurs, emphasizing quality, teamwork, and regional manufacturing workshops. | Food and Beverage Manufacturing | 馃嚝馃嚪 Dieppe | 212 | 2018 |
| 8 | [Pressalit](https://www.tamtam.ai/c/pressalit) (pressalit.com)
A Danish company producing high-quality toilet seats, accessible bathrooms, and height-adjustable kitchens for people with reduced mobility since 1954 | Plastics Manufacturing | 馃嚝馃嚪 Ry | 211 | 1954 |
| 9 | [Nexira](https://www.tamtam.ai/c/nexira) (nexira.com)
Family-owned company, world leader acacia gum, global leader natural ingredients, botanical extracts, food, nutrition, dietary supplements, clean label. | Food and Beverage Manufacturing | 馃嚝馃嚪 Rouen | 200 | 1895 |
| 10 | [Abysse Corp Group](https://www.tamtam.ai/c/abysse-corp-group) (abyssecorp.com)
Design, manufacture, and distribute licensed pop culture merchandise including manga, cinema, video games, with global offices and multiple product lines. | Wholesale | 馃嚝馃嚪 Grand Couronne | 192 | 2003 |
| 11 | [SOGET](https://www.tamtam.ai/c/soget) (soget.fr)
A global leader in Port Community Systems, offering e-Customs solutions, Warehouse Management, and container tracking services to streamline port operations worldwide | IT Services and IT Consulting | 馃嚝馃嚪 Le Havre | 171 | 1983 |
| 12 | [G茅n茅rale de Manutention Portuaire](https://www.tamtam.ai/c/generale-de-manutention-portuaire) (gmportuaire.fr)
Leading French port handling company managing container terminals, exceptional cargo, refrigerated container repair, and inland transport with eco-friendly, digitalized operations. | Transportation, Logistics, Supply Chain and Storage | 馃嚝馃嚪 Le Havre | 127 | |
| 13 | [LEADER](https://www.tamtam.ai/c/leader-octeville-sur-mer) (leader-group.company)
Designs, manufactures, and supplies advanced firefighting and rescue equipment including ventilation fans, fire hoses, thermal cameras, and victim search devices worldwide. | Retail Office Equipment | 馃嚝馃嚪 Octeville-sur-Mer | 127 | 1985 |
| 14 | [ACEREL](https://www.tamtam.ai/c/acerel) (acerel.fr)
Specializing in industrial electrical, automation, robotics, and instrumentation Offering design, manufacturing, integration, and maintenance services with a team of 200 passionate experts Operating in 5 locations | Automation Machinery Manufacturing | 馃嚝馃嚪 Offranville | 125 | 1979 |
| 15 | [SERAPID Group](https://www.tamtam.ai/c/serapid-group) (serapid.com)
Leading provider of Rigid Chain technology for heavy linear motion in industries like kinetic architecture, nuclear, medical, aerospace, automotive, and more worldwide | Industrial Machinery Manufacturing | 馃嚝馃嚪 Martin-脡glise | 119 | 1972 |
| 16 | [2H ENERGY](https://www.tamtam.ai/c/2h-energy) (2henergy.fr)
Specialized in energy systems, providing design, manufacturing, installation, and maintenance services for various sectors including military, nuclear, oil and gas, telecommunications, and healthcare | Industrial Machinery Manufacturing | 馃嚝馃嚪 F茅camp | 111 | 1947 |
| 17 | [Institut national des Sciences appliqu茅es de Rouen](https://www.tamtam.ai/c/institut-national-des-sciences-appliquees-de-rouen) (insa-rouen.fr)
It is a prominent engineering school in Normandy, offering diverse programs, conducting research, and fostering strong industry partnerships for future engineers. | Higher Education | 馃嚝馃嚪 Saint-脡tienne-du-Rouvray | 101 | 1985 |
| 18 | [Compagnie Fluviale de Transport](https://www.tamtam.ai/c/compagnie-fluviale-de-transport) (sogestran.com)
A company that specializes in French barging services and operates as a shipping operator as well | Maritime Transportation | 馃嚝馃嚪 Le Havre | 96 | 1988 |
| 19 | [TUBAO SAS](https://www.tamtam.ai/c/tubao-sas) (tubao.fr)
Specializing in water processing and management, offering high-quality HDPE pipes for various industries, with a focus on innovation, engineering, and project security | Civil Engineering | 馃嚝馃嚪 Saint-Sa毛ns | 93 | 1950 |
| 20 | [DEFION Security NL](https://www.tamtam.ai/c/defion-security-nl) (defion.security)
Provides independent, full-service cybersecurity to reduce risk, ensure compliance, and strengthen resilience, connecting prevention, detection, and response with strategic advisory and research. | Computer and Network Security | 馃嚝馃嚪 Eu | 92 | 1997 |
| 21 | [ARLANXEO ELASTOMERES FRANCE SAS](https://www.tamtam.ai/c/arlanxeo-elastomeres-france-sas) (arlanxeo.fr)
Development, manufacturing, and marketing of high-performance synthetic rubber for automotive, tire, construction, oil, and gas industries across multiple countries. | Chemical Manufacturing | 馃嚝馃嚪 Lillebonne | 89 | 1960 |
| 22 | [Trace Software](https://www.tamtam.ai/c/trace-software) (trace-software.com)
Global leader in CAD & CAE software for industrial engineering, specializing in electrical design Empowering electrical solutions for manufacturing, energy, and transportation industries | Software Development | 馃嚝馃嚪 Saint-Romain-de-Colbosc | 85 | 1987 |
| 23 | [PAUMIER](https://www.tamtam.ai/c/paumier) (paumier-sa.fr)
Design and manufacture of tailored HVAC and refrigerating systems for marine and offshore sectors, including air handling and cooling equipment. | Machinery Manufacturing | 馃嚝馃嚪 F茅camp | 82 | 1963 |
| 24 | [Polytechs](https://www.tamtam.ai/c/polytechs) (polytechs.fr)
Production of masterbatches, compounds, and additive blends for plastics industry, serving polymer producers to recycling companies worldwide. | Plastics Manufacturing | 馃嚝馃嚪 Cany-Barville | 71 | 1980 |
| 25 | [ROUSSEAU - identit茅 visuelle](https://www.tamtam.ai/c/rousseau-identite-visuelle) (rousseau-sa.fr)
An environmentally conscious industrial player specializing in urban furniture, signage, metal structures, and facades for prestigious clients, offering a complete product lifecycle approach | Business Supplies & Equipment | 馃嚝馃嚪 Offranville | 69 | 1921 |
| 26 | [CELEC - Electronics specialist](https://www.tamtam.ai/c/celec-electronics-specialist) (celec.fr)
Design and manufacture of custom electronic automation solutions and sensors for diverse industries, serving global markets with high-quality products. | Computers and Electronics Manufacturing | 馃嚝馃嚪 Neufch芒tel-en-Bray | 69 | 1990 |
| 27 | [MILLB脛KER SAS](https://www.tamtam.ai/c/millbaker-sas) (millbaker.com)
Design and manufacture of ingredient solutions for wheat-flour-bread sector, including flour correctors, bakery improvers, and fermented sourdoughs. | Food and Beverage Manufacturing | 馃嚝馃嚪 Torcy-le-Petit | 63 | 2005 |
| 28 | [Robocath](https://www.tamtam.ai/c/robocath) (robocath.com)
A French medtech company specializes in developing and commercializing robotic solutions for treating cardiovascular diseases, focusing on precision and interventional conditions improvement | Medical Equipment Manufacturing | 馃嚝馃嚪 Rouen | 59 | 2009 |
| 29 | [Groupe SUMPAR](https://www.tamtam.ai/c/groupe-sumpar) (sumpar.com)
specializes in supplying complex metal parts and assemblies for aerospace, offering design, machining, quality control, and assembly services | Industrial Machinery Manufacturing | 馃嚝馃嚪 Boos | 52 | 1975 |
| 30 | [EcoTechnilin](https://www.tamtam.ai/c/ecotechnilin) (eco-technilin.com)
Industrial design and manufacture of technical materials from natural fibers like flax and hemp for advanced composite applications across multiple global markets. | Textile Manufacturing | 馃嚝馃嚪 Valliquerville | 47 | 2005 |
## How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 13, 2026.
## More company lists in the Seine-Maritime department
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- [Manufacturers in the Seine-Maritime department](https://www.tamtam.ai/l/manufacturers-seine-maritime) (72)
- [Public sector organisations in the Seine-Maritime department](https://www.tamtam.ai/l/public-sector-organisations-seine-maritime) (65)
- [Distributors and wholesalers in the Seine-Maritime department](https://www.tamtam.ai/l/distributors-and-wholesalers-seine-maritime) (53)
- [Professional services firms in the Seine-Maritime department](https://www.tamtam.ai/l/professional-services-firms-seine-maritime) (51)
- [Critical infrastructure operators in the Seine-Maritime department](https://www.tamtam.ai/l/critical-infrastructure-operators-seine-maritime) (46)
- [Family-owned companies in the Seine-Maritime department](https://www.tamtam.ai/l/family-owned-companies-seine-maritime) (44)
- [IT services companies in the Seine-Maritime department](https://www.tamtam.ai/l/it-services-companies-seine-maritime) (40)
- [Hardware manufacturers in the Seine-Maritime department](https://www.tamtam.ai/l/hardware-companies-seine-maritime) (38)
- [Education providers in the Seine-Maritime department](https://www.tamtam.ai/l/education-companies-seine-maritime) (36)
- [Healthcare providers in the Seine-Maritime department](https://www.tamtam.ai/l/healthcare-providers-seine-maritime) (34)
- [Logistics companies in the Seine-Maritime department](https://www.tamtam.ai/l/logistics-companies-seine-maritime) (34)
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- [Real Estate companies in the Seine-Maritime department](https://www.tamtam.ai/l/real-estate-companies-seine-maritime) (30)
- [Higher Education companies in the Seine-Maritime department](https://www.tamtam.ai/l/higher-education-companies-seine-maritime) (28)
- [Software Development companies in the Seine-Maritime department](https://www.tamtam.ai/l/software-development-companies-seine-maritime) (28)
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- [Consulting firms in the Seine-Maritime department](https://www.tamtam.ai/l/consulting-firms-seine-maritime) (26)
- [Hospitals and Health Care companies in the Seine-Maritime department](https://www.tamtam.ai/l/hospitals-and-health-care-companies-seine-maritime) (25)
## The same list elsewhere in France
- [Companies with in-house R&D in France](https://www.tamtam.ai/l/r-and-d-companies-france) (8,748)
- [Companies with in-house R&D in 脦le-de-France](https://www.tamtam.ai/l/r-and-d-companies-ile-de-france) (2,695)
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- [Companies with in-house R&D in Provence-Alpes-C么te d'Azur](https://www.tamtam.ai/l/r-and-d-companies-provence-alpes-cote-dazur) (612)
- [Companies with in-house R&D in Nouvelle-Aquitaine](https://www.tamtam.ai/l/r-and-d-companies-nouvelle-aquitaine) (566)
- [Companies with in-house R&D in the Hauts-de-Seine department](https://www.tamtam.ai/l/r-and-d-companies-hauts-de-seine) (510)
- [Companies with in-house R&D in the Rh么ne department](https://www.tamtam.ai/l/r-and-d-companies-rhone) (509)
- [Companies with in-house R&D in Pays de la Loire](https://www.tamtam.ai/l/r-and-d-companies-pays-de-la-loire) (480)
- [Companies with in-house R&D in Hauts-de-France](https://www.tamtam.ai/l/r-and-d-companies-hauts-de-france) (410)
- [Companies with in-house R&D in Brittany](https://www.tamtam.ai/l/r-and-d-companies-brittany) (366)
- [Companies with in-house R&D in the Haute-Garonne department](https://www.tamtam.ai/l/r-and-d-companies-haute-garonne) (323)
- [Companies with in-house R&D in the Bouches-du-Rh么ne department](https://www.tamtam.ai/l/r-and-d-companies-bouches-du-rhone) (320)
- [Companies with in-house R&D in the Is猫re department](https://www.tamtam.ai/l/r-and-d-companies-isere) (304)
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- [Companies with in-house R&D in Normandy](https://www.tamtam.ai/l/r-and-d-companies-normandy) (227)
- [Companies with in-house R&D in the Gironde department](https://www.tamtam.ai/l/r-and-d-companies-gironde) (225)
- [Companies with in-house R&D in the Loire-Atlantique department](https://www.tamtam.ai/l/r-and-d-companies-loire-atlantique) (207)
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## The same list elsewhere
- [Companies with in-house R&D in the world](https://www.tamtam.ai/l/r-and-d-companies-in-the-world) (34,334)
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Source: https://www.tamtam.ai/l/r-and-d-companies-seine-maritime