🏆 Deal of the Week · CW 6/2026
Newcleo raised EUR 75 million in a Venture – Series Unknown funding round; the post-money valuation remains undisclosed. The round attracted a broad coalition of new and existing investors across European industrial and financial sectors. No single lead investor has been publicly identified.
Newcleo — key deal facts
| Company | Newcleo |
| Founded | 2021 |
| Headquarters | London, United Kingdom |
| Amount raised | EUR 75m |
| Valuation | Valuation Remains Undisclosed |
| Round | Venture – Series Unknown |
| Investors | The round welcomed new investors such as Cementir Holding, Danieli & C, and Orion Valves, alongside existing shareholders including Kairos, Indaco Ventures, Azimut Investments, the CERN pension fund, and Walter Tosto. Among the recent additions is NextChem, a MAIRE subsidiary, which joined the capital following its joint venture with Newcleo. |
| Sectors | Clean Energy |
Who invested in Newcleo?
New investors joining the round include Cementir Holding, Danieli & C, and Orion Valves, while existing shareholders Kairos, Indaco Ventures, Azimut Investments, the CERN pension fund, and Walter Tosto continued their support. NextChem, a subsidiary of MAIRE, also joined the capital table following the signing of a joint venture with Newcleo. The investor mix is notable for combining heavy industrial operators with specialist venture and asset-management backers, reflecting the capital-intensive and cross-sector nature of advanced nuclear development.
What does Newcleo do?
Newcleo was founded in 2021 by physicist and entrepreneur Stefano Buono and is headquartered in London, United Kingdom. The company designs and builds Generation IV lead-cooled fast reactors (LFRs) fueled with MOX (mixed uranium-plutonium oxide), enabling the multi-recycling of nuclear waste into new fuel without requiring new uranium mining. Its flagship product is a compact, modular small modular reactor (SMR) aimed at closing the nuclear fuel cycle and delivering safe, stable baseload power for global decarbonization. Newcleo is pursuing licensing and operational partnerships in France, Italy, Slovakia, and the United States.
Newcleo valuation & multiples
Frequently asked questions
How much did Newcleo raise in its Venture – Series Unknown?
Newcleo raised EUR 75 million in a Venture – Series Unknown round; no close date has been publicly disclosed.
What is Newcleo's valuation?
Newcleo's post-money valuation remains undisclosed.
Who invested in Newcleo?
The round included new investors Cementir Holding, Danieli & C, Orion Valves, and NextChem (a MAIRE subsidiary), alongside existing shareholders Kairos, Indaco Ventures, Azimut Investments, the CERN pension fund, and Walter Tosto.
When was Newcleo founded and where is it based?
Newcleo was founded in 2021 and is headquartered in London, United Kingdom.
Source: original announcement — read the full report.