Sienna Venture Capital Research
Investment Thesis
Sienna Venture Capital is the Paris-based venture arm of Sienna Investment Managers, the alternative-investment platform owned by Groupe Bruxelles Lambert (GBL). The firm was founded in 2022 by Isabelle Amiel and Thomas Visan, who had previously built five venture funds together at La Maison Partners. Their pitch is simple: they invest globally, with a strong lean toward Israeli tech, and rely on proprietary dealflow built over more than a decade. The homepage tagline is "Empowering fearless founders shaping the future of tech." They position themselves as trusted, approachable advisors who help companies scale into Europe and the US, and they actively take part in the scale-up phase rather than just writing a check.
Sector Focus
The site lists six focus areas:
- Artificial Intelligence
- Cybersecurity
- Agrifoodtech
- Digital Health
- Mobility
- Industry 4.0
The portfolio also contains semiconductors and photonics for AI data centers (Xsight Labs, DustPhotonics) and insurtech (Hourly). Earlier press described fintech as a target area as well.
Stage Focus
Early growth and growth stage. Sienna is not a seed fund. Its portfolio rounds are mostly Series B and later: Second Nature Series B, Seemplicity Series B, Ibex Series C, DustPhotonics Series B follow-on, Xsight Labs Series E.
Check Size
The firm says it typically invests $5 to $10 million per company. Earlier launch coverage cited $5 to $15 million per round, and a $250 million raise for an Israel-focused fund (Sienna Startup Nation) was reported in 2023.
Lead Tendency
The website states they lead or co-lead rounds. The firm's own press confirms it led Second Nature's $22M Series B (October 2025) and Seemplicity's $50M Series B (August 2025).
Recent Activity
- September 2026: Xsight Labs announced a raise of more than $300 million. Sienna lists Xsight (2026) as its newest portfolio company.
- April 2026: DustPhotonics was acquired by Credo for up to $1.2B, a major exit.
- January 2026: Nexar appointed Yann LeCun to its board.
- December 2025: Zendesk acquired Unleash.
- October 2025: Led Second Nature's $22M Series B.
- August 2025: Led Seemplicity's $50M Series B.
The firm appears to be actively deploying, with a new investment in 2026.
Portfolio Highlights
The site shows nine investments: Xsight Labs, Second Nature, Seemplicity, Unleash, DustPhotonics, Ibex, Nexar, SupPlant and Incredo (formerly DouxMatok), plus Hourly mentioned on partner profiles. Exits include DustPhotonics (Credo) and Unleash (Zendesk). The founders say they have invested in 50+ tech companies across their careers, including at La Maison Partners.
Team
- Isabelle Amiel, Founding & Managing Partner: started at Credit Suisse in 1997 (head of the UHNWI department), co-founded La Maison Partners in 2014, raised five VC funds with over $500M AUM and led 50+ direct tech investments across Israel, Europe, the US and Southeast Asia.
- Thomas Visan, Partner: focuses on cybersecurity, digital health and AI; previously at La Maison Partners (40 investments) and Zilkha Investments in New York.
- Paul-Louis Bisbarre, Associate: joined January 2023, ex Impulse Partners.
- Ines Mas, Associate: joined April 2025, ex Papernest, Houlihan Lokey and Bpifrance.
- Clara de Maubeuge, Executive Assistant.
Decision Process
A small partnership led by Isabelle Amiel and Thomas Visan, with the investment team working under them. No formal committee structure is described publicly. Partners sit on portfolio boards.
Founder Preferences
Ambitious entrepreneurs in deep tech and enterprise software with strong Israeli, European or US scale-up potential. Isabelle has publicly argued that now is the best time to invest in Israeli tech. Events such as the Paris recap with Incredo and the SIAL foodtech talk show an interest in positive-impact founders.
Geographic Focus
Global in principle, with a heavy concentration on Israeli startups (Sienna Startup Nation I and II) and the US, run from Paris. The firm received a CCFI award in November 2024 for supporting Israeli tech.
Gaps
AUM for the venture arm is not stated on the site (the parent Sienna Investment Managers manages about 36 billion euros). The contact page returned a 503 during research, so no email addresses were captured.