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Commonwealth Fusion Systems

Commonwealth Fusion Systems

Private
Devens, MassachusettsEnergy & Sustainabilityhttps://cfs.energy/

Last Round

VC Round

Jul 30, 2026

Est. Valuation

$5B

Total Funding Raised

$2.91B

Momentum

Top 25%

of companies Caplight tracks

Company Overview

Commonwealth Fusion Systems is an energy technology company that designs and constructs fusion machines to deliver clean, limitless fusion energy.

Sector

Energy & Sustainability

Verticals

Renewable Energy, Advanced Materials

Business Model

B2B

Customer Profile

Revenue Share, Services & Consulting, Hardware Sales

AI Layer

Application

Keywords

fusion energyfusion powerhigh-temperature superconducting magnetsHTS magnetstokamakclean energybaseload powerdigital twinnet energy gainpower purchase agreementPPAfusion startupdeep techclimate techcommercial fusion

Historical Pricing

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Caplight Momentum Score

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Commonwealth Fusion Systems Comparables

Compare Commonwealth Fusion Systems with similar companies based on industry and business-model similarity.

Commonwealth Fusion Systems comparables — related companies by embedding similarity
CompanySimilarityMarket Cap
TAE Technologies
85%
Helion
83%
Tokamak Energy
81%

Commonwealth Fusion Systems Funding Rounds

Historical fundraising activity

Data table
RoundDateAmount RaisedValuationInvestorsSources
VC RoundJul 30, 2026
Series B ExtensionAug 28, 2025
Series BDec 1, 2021
Series A ExtensionMay 26, 2020
Series AJun 27, 2019
Seed
Mar 9, 2018

Key People

Founding team and executive leadership

Robert Mumgaard

CEO

Executive Team

Julian Soell

Chief Operating Officer

Executive Team

Commonwealth Fusion Systems Investors

Notable investors and investment history

Commonwealth Fusion Systems investors
InvestorRounds
One Madison GroupSeries B
Development Bank of JapanSeries B, Series B Extension
Fine Structure VenturesSeries A Extension, Series B
Fujikura Ltd.Series B, Series B Extension
TemasekSeries B, Series A Extension
Future VenturesSeries A Extension, Series B, Series A, Series B Extension
Galaxy InteractiveSeries B, Series B Extension

Market signals

Structured signals derived from secondary market and firmographic data.

  • Apr 21, 2026

    Experts gathered for the second Boundary Collaborators Workshop.

  • Mar 4, 2026

    SPARC tokamak assembly underway, targeting 140MW fusion power.

Commonwealth Fusion Systems Filings

SEC and related filings with document metadata.

Data table
TypedDateAmount OfferedAmount SoldFillingPagesDownload
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Commonwealth Fusion Systems Filings

SEC and related filings with document metadata.

Appears On

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Frequently Asked Questions

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Firmographic Details

HeadquartersDevens, Massachusetts
Employee Range1,089
Year Founded2018
Last FundingJul 30, 2026

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