# The 26 largest companies with in-house R&D in Massy
Tamtam tracks 26 companies with in-house R&D headquartered in Massy. This list ranks all of them by number of employees on LinkedIn, led by R茅seau DEF, Orano DS and Infovista. Their median headcount is 49. Half of them were founded in 2012 or later.
The companies with in-house R&D in Massy are primarily mid-sized firms in software development, manufacturing, and specialized industrial services. Noteworthy examples include R茅seau DEF, an international network for fire safety systems; Orano DS, providing nuclear expertise; Infovista, which optimizes network performance; and Horoquartz, offering workforce management solutions. MyUnisoft develops accounting platforms, while Exotrail focuses on space mobility systems.
A significant cluster of these companies operates in software development, with firms like Infovista, Horoquartz, MyUnisoft, and CODRA all headquartered in Massy. This concentration suggests a local specialization in digital solutions, alongside a strong presence in industrial and high-tech manufacturing.
馃嚝馃嚪 Massy 路 26 companies 路 Updated Nov 11, 2026
| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [R茅seau DEF](https://www.tamtam.ai/c/reseau-def) (reseau-def.com)
International network of expert companies providing detection, extinguishing, smoke extraction, and exit management systems through manufacturing and research facilities across several countries. | Appliances, Electrical, and Electronics Manufacturing | 馃嚝馃嚪 Massy | 3,484 | 1958 |
| 2 | [Orano DS](https://www.tamtam.ai/c/orano-ds) (orano.group)
Provides expertise and solutions to nuclear operators in industrial logistics, specialized maintenance, radiological safety, decommissioning, and waste management. | Nuclear Electric Power Generation | 馃嚝馃嚪 Massy | 2,118 | 2018 |
| 3 | [Infovista](https://www.tamtam.ai/c/infovista) (infovista.com)
Empowers service providers and enterprises with data-driven solutions for optimizing network performance, enhancing customer experience, and driving business success. | Software Development | 馃嚝馃嚪 Massy | 834 | 1995 |
| 4 | [Horoquartz](https://www.tamtam.ai/c/horoquartz) (horoquartz.com)
Provides integrated solutions for workforce management, planning optimization, activity tracking, access control, and identity management, serving over 5000 clients globally. | Software Development | 馃嚝馃嚪 Massy | 568 | 1971 |
| 5 | [MyUnisoft](https://www.tamtam.ai/c/myunisoft) (myu.fr)
Develops a collaborative cloud platform for accounting firms, simplifying daily tasks, automating workflows, and enhancing client relationships with integrated financial management and e-invoicing compliance. | Accounting | 馃嚝馃嚪 Massy | 242 | 2018 |
| 6 | [Exotrail](https://www.tamtam.ai/c/exotrail) (exotrail.com)
Develops and operates propulsion systems, mission simulation software, and orbital transfer vehicles for efficient, sustainable space mobility, enabling telecommunication, Earth observation, space exploration. | Defense and Space Manufacturing | 馃嚝馃嚪 Massy | 215 | 2015 |
| 7 | [ADALTRA](https://www.tamtam.ai/c/adaltra) (adaltra.fr)
Specializing in communication systems for various environments such as offices, hotels, hospitals, airports, stadiums, and more, our solutions are designed by CAE GROUPE | Manufacturing | 馃嚝馃嚪 Massy | 182 | |
| 8 | [CODRA](https://www.tamtam.ai/c/codra) (codra.net)
Specializing in industrial IT, our company offers automation and test system services while also developing and distributing software solutions for various industries | Software Development | 馃嚝馃嚪 Massy | 181 | 1986 |
| 9 | [Quandela](https://www.tamtam.ai/c/quandela) (quandela.com)
Specializing in photon-based quantum computing and cloud solutions to assist organizations in achieving quantum transformation | Nanotechnology Research | 馃嚝馃嚪 Massy | 157 | 2017 |
| 10 | [iObeya](https://www.tamtam.ai/c/iobeya) (iobeya.com)
Transforms physical workspaces into immersive, collaborative digital environments for sharing KPIs, plans, and ideas, fostering collective intelligence and quick decision-making. | Software Development | 馃嚝馃嚪 Massy | 156 | 2011 |
| 11 | [L枚wenstein Medical France](https://www.tamtam.ai/c/lowenstein-medical-france) (loewensteinmedical.com)
Development and supply of reliable respiratory assistance devices for hospitals and home care, focusing on patient quality of life and support. | Medical Equipment Manufacturing | 馃嚝馃嚪 Massy | 72 | 1996 |
| 12 | [Mecalectro](https://www.tamtam.ai/c/mecalectro-massy) (mecalectro.com)
Design and manufacture of custom electromagnetic actuators, locks, and safety latches for aerospace, defense, medical, and other sectors. | Aviation and Aerospace Component Manufacturing | 馃嚝馃嚪 Massy | 56 | 1948 |
| 13 | [Hamamatsu Photonics France](https://www.tamtam.ai/c/hamamatsu-photonics-france) (hamamatsu.com)
Manufactures optoelectronic components, modules, and systems covering the entire optical spectrum for demanding applications in medical, automotive, science, environmental, analytical, and industrial processes. | Semiconductor Manufacturing | 馃嚝馃嚪 Massy | 49 | 1985 |
| 14 | [Cuenod](https://www.tamtam.ai/c/cuenod) (cuenod.com)
With over 120 years of experience, this European burner manufacturer offers a wide range of environmentally-friendly heating solutions for residential, commercial, and industrial applications | Machinery Manufacturing | 馃嚝馃嚪 Massy | 46 | 1899 |
| 15 | [Cyberwatch](https://www.tamtam.ai/c/cyberwatch) (cyberwatch.fr)
French cybersecurity solutions provider, specializing in vulnerability and compliance management, offering penetration testing services and job opportunities. | Computer and Network Security | 馃嚝馃嚪 Massy | 42 | 2015 |
| 16 | [Sensome](https://www.tamtam.ai/c/sensome) (sensome.com)
Innovative start-up developing remote monitoring technology to transform invasive medical devices into connected healthcare devices EN ISO 13485:2016 certified | Medical Equipment Manufacturing | 馃嚝馃嚪 Massy | 40 | 2014 |
| 17 | [SpaceDreamS](https://www.tamtam.ai/c/spacedreams) (spacedreams.com)
Provides turnkey ground segment solutions, operational maintenance, launch services, and digital twins using modular, interoperable systems to reduce costs for European spaceports. | Aviation and Aerospace Component Manufacturing | 馃嚝馃嚪 Massy | 36 | 2021 |
| 18 | [Mecalectro](https://www.tamtam.ai/c/mecalectro) (mecalectro.com)
A European leader in electromagnetic solutions, offering a wide range of products such as electromagnets, electromagnet suction cups, safety locks, and electrodynamic actuators They provide innovative and reliable solutions for demanding markets | Industrial Machinery Manufacturing | 馃嚝馃嚪 Massy | 20 | 1948 |
| 19 | [AEROMAPPER](https://www.tamtam.ai/c/aeromapper) (aeromapper.com)
Designs and manufactures innovative unmanned aerial vehicles for surveillance, reconnaissance, and intelligence missions, serving both civil and military clients with high-performance, reliable solutions. | Aviation and Aerospace Component Manufacturing | 馃嚝馃嚪 Massy | 20 | 2012 |
| 20 | [Geoflex](https://www.tamtam.ai/c/geoflex) (geoflex.xyz)
Enhances GPS/GNSS applications to 4-centimeter accuracy for trains, cars, vessels, drones, and smartphones using patented technology and experienced team. | IT Services and IT Consulting | 馃嚝馃嚪 Massy | 18 | 2012 |
| 21 | [Cryo Pur](https://www.tamtam.ai/c/cryo-pur) (cryopur.com)
Specializing in gas separation and liquefaction, the company offers innovative equipment for various applications such as biogas upgrading, CO2 capture, and natural gas microliquefaction | Industrial Machinery Manufacturing | 馃嚝馃嚪 Massy | 11 | 2015 |
| 22 | [Diota](https://www.tamtam.ai/c/diota) (3ds.com)
Develops software solutions optimizing industrial performance through interactive digital continuity between engineering and field operations using advanced technologies, maximizing quality, traceability, and productivity. | IT Services and IT Consulting | 馃嚝馃嚪 Massy | 10 | 2009 |
| 23 | [HUB Parking Technology FR](https://www.tamtam.ai/c/hub-parking-technology-fr) (hubparking.fr)
Innovative parking technology company: develops, installs, and supports Parking Access and Revenue Control Systems worldwide Offers scalable solutions with remote management capabilities | IT Services and IT Consulting | 馃嚝馃嚪 Massy | 5 | 2015 |
| 24 | [Kos lighting](https://www.tamtam.ai/c/kos-lighting) (koslighting.eu)
A leading French company specializing in designing and manufacturing LED lighting fixtures and accessories, focused on providing innovative solutions for visual comfort and energy efficiency | Design Services | 馃嚝馃嚪 Massy | 4 | |
| 25 | [DEVERNE](https://www.tamtam.ai/c/deverne) (deverne-france.com)
Engineering firm specializing in embedded video systems, optronic solutions, and artificial intelligence for defense, mobility, surveillance, and medical diagnostics. | Appliances, Electrical, and Electronics Manufacturing | 馃嚝馃嚪 Massy | 4 | 2021 |
| 26 | [MilliDrop](https://www.tamtam.ai/c/millidrop) (millidrop.fr)
Develops and sells microbiology systems for incubating, analyzing, and handling thousands of nanoliter-scale samples in parallel, catering to research, industrial, and diagnostic sectors | Biotechnology Research | 馃嚝馃嚪 Massy | 3 | 2015 |
## 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 11, 2026.
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Source: https://www.tamtam.ai/l/r-and-d-companies-massy