HISTORICAL P100 / #88

Commonwealth Fusion Systems

Fusion Energy · United States

Historical ranking valuation$2.60BSource snapshot: Jun 19, 2026

Disclosed primary funding in this record

$2.1B

Sum of non-overlapping disclosed USD amounts in confirmed primary financing entries in this record, including separately labeled equity components; not verified lifetime funding. Excludes amounts already included in a later round, announced, reported, database-only, debt, secondary and unclassified events.

4 confirmed primary rounds with disclosed USD amounts · Record through 2026-09-25

THE BUSINESS

Get to know Commonwealth Fusion Systems.

Commonwealth Fusion Systems develops high-temperature superconducting magnets and tokamak fusion systems. It describes SPARC as a machine under development and ARC as a planned power plant, not as already operating commercial generation.

Commonwealth Fusion Systems technology overview ↗Source checked Sep 24, 2026

Valuation history

Valuations reported at the time of each round.

No dated financing valuation has passed into this record.

Funding history

Funding rounds, debt and other financing events.

7sourced events · record as of 2026-09-25

Not a legal funding register. CFS confirms $1B new equity in July 2026, $863M B2 in 2025, more than $1.8B B in 2021, $84M A2 in 2020 and $115M A in 2019. The B is lower-bounded and excluded from exact-dollar sums. Hyundai invested within the July $1B, not an extra round. Plynth's June 2026 stake has no disclosed amount or proven overlap. Eni's 2018 initial $50M may be included in the 2019 A disclosure, so it is not added again. PPAs and commercial contracts are not capital.

Jul 30, 2026LATEST SOURCED

primary

Additional equity financing (series not stated)

Hyundai Motor Group

CFS explicitly calls this $1B additional equity. Its later Hyundai announcement places Hyundai within this same fundraise; CFS does not name a lead or disclose Hyundai's allocation. The existing generated article has not been independently corrected or reviewed here.

Amount$1BValuationUndisclosed

Jun 11, 202606

other

Plynth Energy minority stake

Plynth Energy

CFS says Plynth acquired a minority stake but gives no amount, issuer-versus-existing-holder structure or relationship to the $1B announced in July.

AmountUndisclosed; overlap with later $1B not resolvedValuationUndisclosed

Aug 28, 202505

primary

Series B2

Brevan Howard Macro Venture Fund · Counterpoint Global (Morgan Stanley) · Gigascale Capital · HOF Capital · Neva SGR · NVentures · Planet First Partners · Woori Venture Partners US · +5 more

CFS discloses $863M and named new/existing participants, but no lead or per-investor allocations. The consortium and Google/Eni participation are within this round, not additional financing rows.

Amount$863MValuationUndisclosed

Dec 1, 202104

primary

Series B

Tiger Global Management (lead) · Bill Gates · Coatue · DFJ Growth · Emerson Collective · Google · Eni · Breakthrough Energy Ventures · +3 more

CFS says the closed Series B exceeded $1.8B. It does not supply an exact final amount; the lower bound is not rounded into an exact USD subtotal.

AmountMore than $1.8BValuationUndisclosed

May 26, 202003

primary

Series A2

Temasek (lead) · Equinor · Devonshire Investors · Breakthrough Energy Ventures · The Engine · Eni Next · Future Ventures · Hostplus · +1 more

CFS calls this additional A2 funding and says cumulative company funding exceeded $200M; the cumulative figure is not another round.

Amount$84MValuationUndisclosed

Jun 27, 201902

primary

Series A closing

Future Ventures · Khosla Ventures · Lowercase Capital · Moore Strategic Ventures · Safar Partners · Schooner Capital · Starlight Ventures · Eni · +2 more

CFS announces $115M at Series A close, naming new participants joining Eni and earlier investors. It does not allocate the total among the earlier tranches.

Amount$115MValuationUndisclosed

201801

other

Eni initial equity investment

Eni

Eni signed for an initial $50M equity stake and its 2018 annual report later records ownership. The exact primary/secondary structure and overlap with CFS's 2019 Series A close are not established; do not add this amount twice.

Amount$50M initial investmentValuationUndisclosed

Financing participants

Investors, lenders and other parties named in funding announcements.

Hyundai Motor Group

Additional equity financing (series not stated) · Jul 30, 2026 · Participant · primary · Confirmed · Confirmed source ↗