Key facts
- Onsen’s last known valuation is $5.9M (Dec 2025).
- It has raised $1.5M; the latest was Later Stage VC ($1.5M) in Dec 2025.
- Notable investors include Demea Sustainable Investment, Greentech Innovation (France).
- Status: Privately Held (backing).
- ·The complete investor list — 2 names
- ·Watchlist + deal alerts for Onsen
- ·The full record, as it builds
Funding rounds
No funding rounds for Onsen are on record yet — either the company hasn't raised institutional capital, or the raise hasn't surfaced in our sources.
About Onsen
Operator of an environmental engineering and energy efficiency firm intended to design, manufacture, and install the blue degree hot water system. The company specializes in developing systems to improve water and energy efficiency in aquatic facilities, particularly public and private swimming pools, enabling facilities to reduce energy use, cut water consumption, and comply with environmental regulations.
- Sector
- Energy
- HQ
- Villeurbanne, France
- Founded
- 2009
- Employees
- 22
- Website
- onsen-sas.com/
- Ownership
- Privately Held (backing)
Onsen doesn't have a composite mark yet — a PA Mark is published once enough pricing inputs exist (trade prints, fund marks, round prices). The rest of the record below builds toward it.
Recorded secondary trades
No secondary trades in Onsen shares have been recorded yet. When a print lands — third-party, direct report, or platform — it appears here with structure, source, and price.
Institutional fund marks
No SEC-registered fund has reported a fair-value mark on Onsen in its N-PORT filings yet. We sweep new filings monthly.