# The 30 largest SaaS companies in the Essonne department

Tamtam tracks 41 SaaS companies headquartered in the Essonne department. This list ranks the 30 largest by number of employees on LinkedIn, led by Infovista, G4 and MyUnisoft. Their median headcount is 21. Half of them were founded in 2008 or later. The most common headquarters are Massy (11), Palaiseau (4) and Orsay (3).

The SaaS companies in Essonne are primarily software development and IT services firms. Companies such as Infovista, with 834 employees, focus on network performance solutions, while MyUnisoft (242 employees) develops collaborative accounting platforms. iObeya (156 employees) transforms physical workspaces into digital environments, and MEDIA IMMO (200 employees) provides digital solutions for real estate professionals. Olfeo (50 employees) specializes in internet content filtering, and Cyberwatch (42 employees) offers cybersecurity solutions.

Many of these companies, like Infovista, MyUnisoft, iObeya, Aprovall, Olfeo, and Cyberwatch, are headquartered in Massy, indicating a concentration of SaaS businesses in this city within Essonne. The founding dates span from 1995 (Infovista) to 2023 (Sylq), showing a mix of established firms and newer ventures.

🇫🇷 Essonne · 30 companies · Updated Nov 11, 2026

| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [Infovista](https://www.tamtam.ai/c/infovista) (infovista.com)<br>Empowers service providers and enterprises with data-driven solutions for optimizing network performance, enhancing customer experience, and driving business success. | Software Development | 🇫🇷 Massy | 834 | 1995 |
| 2 | [G4](https://www.tamtam.ai/c/g4) (g4.fr)<br>G4 specializes in streamlining information management within companies, optimizing tools for strategic alignment and providing practical support and expertise | Information Services | 🇫🇷 Arpajon | 254 | 2006 |
| 3 | [MyUnisoft](https://www.tamtam.ai/c/myunisoft) (myu.fr)<br>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 | 🇫🇷 Massy | 242 | 2018 |
| 4 | [MEDIA IMMO](https://www.tamtam.ai/c/media-immo) (media-immo.fr)<br>Provides digital solutions for generating risk reports and urban planning documents specifically designed for real estate professionals. | Software Development | 🇫🇷 Corbeil-Essonnes | 200 |  |
| 5 | [iObeya](https://www.tamtam.ai/c/iobeya) (iobeya.com)<br>Transforms physical workspaces into immersive, collaborative digital environments for sharing KPIs, plans, and ideas, fostering collective intelligence and quick decision-making. | Software Development | 🇫🇷 Massy | 156 | 2011 |
| 6 | [Sylq](https://www.tamtam.ai/c/sylq) (sylq.io)<br>A European payment platform offering cards, bank payments, and cryptocurrencies for merchants, with a focus on simplifying transactions and rewarding loyalty | Financial Services | 🇫🇷 Villejust | 67 | 2023 |
| 7 | [Aprovall](https://www.tamtam.ai/c/aprovall) (aprovall.com)<br>Comprehensive third-party lifecycle management platform supporting evaluation, onboarding, monitoring, and off-boarding across legal, finance, cybersecurity, and ethics domains. | Software Development | 🇫🇷 Massy | 61 | 2008 |
| 8 | [Olfeo](https://www.tamtam.ai/c/olfeo) (olfeo.com)<br>A French company specializing in Internet content filtering solutions, optimizing internal and external user access, including mobile devices, with five complementary products | IT Services and IT Consulting | 🇫🇷 Massy | 50 | 2003 |
| 9 | [Cyberwatch](https://www.tamtam.ai/c/cyberwatch) (cyberwatch.fr)<br>French cybersecurity solutions provider, specializing in vulnerability and compliance management, offering penetration testing services and job opportunities. | Computer and Network Security | 🇫🇷 Massy | 42 | 2015 |
| 10 | [ISI](https://www.tamtam.ai/c/isi) (isicrunch.com)<br>Development of SaaS platforms enabling publishers to create accessible, enriched digital textbooks and e-learning modules for learners with disabilities. | IT Services and IT Consulting | 🇫🇷 Gif-sur-Yvette | 41 | 2003 |
| 11 | [Coffreo](https://www.tamtam.ai/c/coffreo) (coffreo.biz)<br>The company provides HR dematerialization services for BtoB and BtoC customers, offering savings, environmental benefits, and secure storage for important documents | IT Services and IT Consulting | 🇫🇷 Orsay | 40 | 2007 |
| 12 | [Interact Software](https://www.tamtam.ai/c/interact-software) (interact-software.com)<br>This French company specializes in End User Experience and Digital Experience Management solutions for large organizations, aiming to improve user satisfaction and optimize IT assets | Software Development | 🇫🇷 Wissous | 29 | 2014 |
| 13 | [AMPHITRITE](https://www.tamtam.ai/c/amphitrite-palaiseau) (amphitrite.fr)<br>Specialized in advanced satellite and in-situ data processing for maritime decision-making, offering solutions for green shipping, defense, and environmental applications through end-user products. | Software Development | 🇫🇷 Palaiseau | 23 | 2021 |
| 14 | [DAMAaaS](https://www.tamtam.ai/c/damaaas) (damaaas.com)<br>INAGUA offers DAMAaaS, a platform for custom business applications with no coding, enabling efficient workflow collaboration, document management, and data security | Software Development | 🇫🇷 Juvisy-sur-Orge | 22 | 2012 |
| 15 | [SpinalCom](https://www.tamtam.ai/c/spinalcom) (spinalcom.com)<br>Develops sovereign software for building and infrastructure management. Its platform optimizes spaces, maintenance, energy, and unifies fragmented building data for smart operations. | Software Development | 🇫🇷 Palaiseau | 21 | 2009 |
| 16 | [WAVESOFT](https://www.tamtam.ai/c/wavesoft) (wavesoft.fr)<br>French software publisher specializing in management software for small to medium-sized businesses in Trade, Services, and Light Industry sectors Offers nine software modules | Software Development | 🇫🇷 Orsay | 21 | 2003 |
| 17 | [Immanens](https://www.tamtam.ai/c/immanens) (immanens.com)<br>Immanens is a young company focused on electronic information services, offering innovative software products, business services, and project development support | Technology, Information and Internet | 🇫🇷 Palaiseau | 21 | 2004 |
| 18 | [EKILOG](https://www.tamtam.ai/c/ekilog) (ekilog.fr)<br>French software editor providing four integrated solutions for Microsoft 365, enhancing communication, automation, document management, and directory features within SharePoint and Teams. | Software Development | 🇫🇷 Saclay | 20 | 2010 |
| 19 | [Dir IPS](https://www.tamtam.ai/c/dir-ips) (dirips.com)<br>Development of IT solutions for healthcare, social, and medico-social sectors focusing on budgeting, staffing, user tracking, and regulatory compliance. | Software Development | 🇫🇷 Épinay-sur-Orge | 19 | 1993 |
| 20 | [AFIDIUM](https://www.tamtam.ai/c/afidium) (afidium.com)<br>Afidium provides innovative B2B solutions for businesses in the tourism sector, optimizing revenue and profitability across Europe with tailor-made solutions | Software Development | 🇫🇷 Massy | 17 | 2005 |
| 21 | [API - Advanced Prologue Innovation](https://www.tamtam.ai/c/api-advanced-prologue-innovation) (api-sas.fr)<br>A digital transition partner specializing in electronic invoices, EDIFACT exchanges, Chorus Pro integration, and electronic signature solutions for businesses of all sizes | Software Development | 🇫🇷 Les Ulis | 15 | 1986 |
| 22 | [e-Attestations.com](https://www.tamtam.ai/c/e-attestations-com) (e-attestations.com)<br>Provides online platform for secure digital attestations, enabling individuals and organizations to verify and certify documents efficiently and reliably. | Software Development | 🇫🇷 Massy | 14 | 2008 |
| 23 | [ACKOMAS](https://www.tamtam.ai/c/ackomas) (ackomas.com)<br>Provides automated SaaS solutions for medical device manufacturers and professionals, ensuring seamless regulatory compliance across global databases like EUDAMED, GUDID, and SFDA. | IT Services and IT Consulting | 🇫🇷 Palaiseau | 14 | 2021 |
| 24 | [AEXAE](https://www.tamtam.ai/c/aexae) (aexae.fr)<br>A software company headquartered in Les Ulis, France, specializing in computer software development and solutions | Software Development | 🇫🇷 Les Ulis | 13 |  |
| 25 | [CODRA \| INDUSTRIE \| COOX MES](https://www.tamtam.ai/c/codra-industrie-coox-mes) (industry.codra.net)<br>Development and provision of innovative industrial software solutions supporting production monitoring, quality assurance, traceability, and continuous improvement for manufacturers. | Software Development | 🇫🇷 Massy | 12 | 1989 |
| 26 | [Express-Mailing](https://www.tamtam.ai/c/express-mailing) (express-mailing.com)<br>Express-Mailing® offers user-friendly marketing tools for managing email, fax, SMS, and voice campaigns securely, with simple interfaces for real-time tracking | Advertising Services | 🇫🇷 Villejust | 11 | 2002 |
| 27 | [Adents](https://www.tamtam.ai/c/adents) (antaresvisiongroup.com)<br>A leading provider of serialization solutions for product identification and traceability in the pharmaceutical industry, helping companies comply with regulations | Software Development | 🇫🇷 Massy | 11 | 2007 |
| 28 | [AXISCOPE](https://www.tamtam.ai/c/axiscope) (axiscope.com)<br>French software publisher offering collaborative solution for digitalizing procurement & supplier quality processes globally, enhancing purchasing efficiency, supplier relations & quality management | Software Development | 🇫🇷 Orsay | 10 | 2013 |
| 29 | [Diota](https://www.tamtam.ai/c/diota) (3ds.com)<br>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 | 🇫🇷 Massy | 10 | 2009 |
| 30 | [Zoe Care](https://www.tamtam.ai/c/zoe-care) (zoe.care)<br>The company utilizes patented AI technology for elderly care, detecting falls, abnormal behavior, and habit changes through Wi-Fi radio analysis | Software Development | 🇫🇷 Gif-sur-Yvette | 9 | 2022 |

## 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.

## More company lists in the Essonne department

- [The largest companies in the Essonne department](https://www.tamtam.ai/l/largest-companies-essonne) (1,149)
- [Companies with in-house R&D in the Essonne department](https://www.tamtam.ai/l/r-and-d-companies-essonne) (198)
- [Multinational companies in the Essonne department](https://www.tamtam.ai/l/multinational-companies-essonne) (156)
- [Manufacturers in the Essonne department](https://www.tamtam.ai/l/manufacturers-essonne) (127)
- [Hardware manufacturers in the Essonne department](https://www.tamtam.ai/l/hardware-companies-essonne) (114)
- [Distributors and wholesalers in the Essonne department](https://www.tamtam.ai/l/distributors-and-wholesalers-essonne) (76)
- [IT Services and IT Consulting companies in the Essonne department](https://www.tamtam.ai/l/it-services-and-it-consulting-companies-essonne) (70)
- [Professional services firms in the Essonne department](https://www.tamtam.ai/l/professional-services-firms-essonne) (68)
- [Public sector organisations in the Essonne department](https://www.tamtam.ai/l/public-sector-organisations-essonne) (66)
- [Aerospace and defence companies in the Essonne department](https://www.tamtam.ai/l/aerospace-and-defense-companies-essonne) (65)
- [IT services companies in the Essonne department](https://www.tamtam.ai/l/it-services-companies-essonne) (60)
- [Retail chains in the Essonne department](https://www.tamtam.ai/l/retail-chains-essonne) (59)
- [Construction companies in the Essonne department](https://www.tamtam.ai/l/construction-companies-essonne) (56)
- [Software Development companies in the Essonne department](https://www.tamtam.ai/l/software-development-companies-essonne) (51)
- [Pharmaceutical companies in the Essonne department](https://www.tamtam.ai/l/pharmaceutical-companies-essonne) (45)
- [Electronics and semiconductor companies in the Essonne department](https://www.tamtam.ai/l/electronics-companies-essonne) (44)
- [Research institutes in the Essonne department](https://www.tamtam.ai/l/research-institutes-essonne) (42)
- [Events Services companies in the Essonne department](https://www.tamtam.ai/l/events-services-companies-essonne) (41)
- [Consulting firms in the Essonne department](https://www.tamtam.ai/l/consulting-firms-essonne) (40)
- [Family-owned companies in the Essonne department](https://www.tamtam.ai/l/family-owned-companies-essonne) (38)
- [Contract manufacturers in the Essonne department](https://www.tamtam.ai/l/contract-manufacturers-essonne) (35)
- [Research Services companies in the Essonne department](https://www.tamtam.ai/l/research-services-companies-essonne) (35)
- [Critical infrastructure operators in the Essonne department](https://www.tamtam.ai/l/critical-infrastructure-operators-essonne) (32)
- [Education providers in the Essonne department](https://www.tamtam.ai/l/education-companies-essonne) (30)

## The same list elsewhere in France

- [SaaS companies in Île-de-France](https://www.tamtam.ai/l/saas-companies-ile-de-france) (2,859)
- [SaaS companies in Auvergne-Rhône-Alpes](https://www.tamtam.ai/l/saas-companies-auvergne-rhone-alpes) (476)
- [SaaS companies in the Hauts-de-Seine department](https://www.tamtam.ai/l/saas-companies-hauts-de-seine) (389)
- [SaaS companies in Occitanie](https://www.tamtam.ai/l/saas-companies-occitanie) (317)
- [SaaS companies in Provence-Alpes-Côte d'Azur](https://www.tamtam.ai/l/saas-companies-provence-alpes-cote-dazur) (285)
- [SaaS companies in the Rhône department](https://www.tamtam.ai/l/saas-companies-rhone) (284)
- [SaaS companies in Nouvelle-Aquitaine](https://www.tamtam.ai/l/saas-companies-nouvelle-aquitaine) (236)
- [SaaS companies in Grand Est](https://www.tamtam.ai/l/saas-companies-grand-est) (216)
- [SaaS companies in Hauts-de-France](https://www.tamtam.ai/l/saas-companies-hauts-de-france) (194)
- [SaaS companies in Pays de la Loire](https://www.tamtam.ai/l/saas-companies-pays-de-la-loire) (180)
- [SaaS companies in the Nord department](https://www.tamtam.ai/l/saas-companies-nord) (163)
- [SaaS companies in the Haute-Garonne department](https://www.tamtam.ai/l/saas-companies-haute-garonne) (147)
- [SaaS companies in the Bouches-du-Rhône department](https://www.tamtam.ai/l/saas-companies-bouches-du-rhone) (146)
- [SaaS companies in the Gironde department](https://www.tamtam.ai/l/saas-companies-gironde) (141)
- [SaaS companies in the Loire-Atlantique department](https://www.tamtam.ai/l/saas-companies-loire-atlantique) (135)
- [SaaS companies in Brittany](https://www.tamtam.ai/l/saas-companies-brittany) (128)
- [SaaS companies in the Hérault department](https://www.tamtam.ai/l/saas-companies-herault) (110)
- [SaaS companies in the Ille-et-Vilaine department](https://www.tamtam.ai/l/saas-companies-ille-et-vilaine) (85)
- [SaaS companies in Paris](https://www.tamtam.ai/l/saas-companies-paris) (2,218)
- [SaaS companies in Lyon](https://www.tamtam.ai/l/saas-companies-lyon) (211)
- [SaaS companies in Lille](https://www.tamtam.ai/l/saas-companies-lille) (104)
- [SaaS companies in Toulouse](https://www.tamtam.ai/l/saas-companies-toulouse) (102)
- [SaaS companies in Nantes](https://www.tamtam.ai/l/saas-companies-nantes) (90)
- [SaaS companies in Bordeaux](https://www.tamtam.ai/l/saas-companies-bordeaux) (88)

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Source: https://www.tamtam.ai/l/saas-companies-essonne