# Commonwealth Fusion Systems Startup profile on Capital Atlas: https://capitalatlas.ai/startups/commonwealth-fusion-systems - Industry: Power & Utilities - Headquarters: Devens, US - Website: www.cfs.energy - Total disclosed funding: $2.9B - Latest round: Series B (Aug 28, 2025) - Investors on record: 54 ## About Based in Massachusetts, US, and founded in 2018 by CEO Bob Mumgaard and CSO Brandon Sorbom, Commonwealth Fusion Systems LLC, a spin-off of MIT develops a suite of HTS (high-temperature superconductor) magnet technology that enables enterprises to produce energy by combining an inexhaustible power plant with rare-earth barium copper oxide. In August 2025, Commonwealth Fusion Systems LLC raised USD 863 million in series B funding co-led by new investors Mitsui & Co. and Mitsubishi Corporation, with participation from other new investors Bill & Melinda Gates Foundation Trust, Development Bank of Japan, Fujikura Components Ltd., JERA Co., Inc., JGC Holdings, Mitsui Fudosan, Mitsui O.S.K. Lines, Nippon Telegraph and Telephone, Sumitomo Mitsui Banking Corporation, Sumitomo Mitsui Trust Bank Kansai Electric Power, Brevan Howard Investment Management, Morgan Stanley, FFA Private Bank, Galaxy Asset Management, Gigascale Capital, HOF Capital, Neva, NVentures, Planet First Partners, and Woori Venture Partners. Returning investors GV, Emerson Collective, Eni, Future Ventures, Khosla Ventures, Lowercarbon Capital, and Breakthrough Energy Ventures, along with individual and other unspecified investors, also participated in the round. Commonwealth Fusion Systems develops fusion energy systems through rare-earth barium copper oxide superconductor technology. In addition, the company is focusing on providing new yttrium barium copper oxide high-temperature superconducting magnet technologies. The company has developed HTS (high-temperature semiconductors) technology to build high-field large-bore superconducting magnets. The company has collaborated with MIT’s Plasma Science and Fusion Center (PSFC) to design and build SPARC, which is net energy compact fusion system. The company intends to use the August 2025 funding to accelerate fusion energy commercialization, expand global partnerships, and deliver scalable, clean power for future energy demands. ## Funding rounds - Series B, Aug 28, 2025, $863M — Morgan Stanley Investment Management, Sumitomo Mitsui Trust Bank, Gates Foundation Trust, NTT, Development Bank of Japan, Kansai Electric Power, Khosla Ventures, Sumitomo Mitsui Banking Corporation, GV, FFA Private Bank, Mitsubishi Corporation, WOORI Venture Partners, Mitsui & Co., Breakthrough Energy Ventures, HOF Capital, Future Ventures, Neva, Galaxy Asset Management, Mitsui Fudosan, JGC Holdings, Eni, Lowercarbon Capital, Planet First Partners, Mitsui O.S.K. Lines, Fujikura Components Ltd., Brevan Howard US Investment Management, Gigascale Capital, NVentures, Emerson Collective, JERA Co., Inc. - Series B, Nov 19, 2021, $1.8B — Temasek Holdings, Hostplus, Soros Fund Management, Khosla Ventures, Tiger Global Management, GV, Coatue Management, Salesforce, Inc., DFJ Growth, Schooner Capital, Breakthrough Energy Ventures, Senator Investment Group, Engine Ventures, Emerson Collective, Starlight Ventures, Future Ventures, Moore Strategic Ventures, Safar Partners, Eni Next, JS Capital, Lowercarbon Capital, FootPrint Coalition, HALJ Group, Time Ventures, Fine Structure Ventures, Jameel Investment Management Company, Equinor Ventures - Series A, May 11, 2020, $81M — Temasek Holdings, Hostplus, Khosla Ventures, F-Prime Capital, Schooner Capital, Breakthrough Energy Ventures, Engine Ventures, Starlight Ventures, Future Ventures, Moore Strategic Ventures, Safar Partners, Eni Next, Equinor Ventures - Series A, Jul 1, 2019, $50M — Khosla Ventures, Lowercase Capital, Schooner Capital, Starlight Ventures, Future Ventures, Moore Strategic Ventures, Safar Partners - Seed, Jun 17, 2019 — Beni Venture Capital - Series A, May 30, 2018, $65M — Breakthrough Energy Ventures, Engine Ventures, Eni Next ## Investors - Breakthrough Energy Ventures (https://capitalatlas.ai/funds/breakthrough-energy-ventures) — Series A, Series B - Engine Ventures (https://capitalatlas.ai/funds/engine-ventures) — Series A, Series B - Eni Next (https://capitalatlas.ai/funds/eni-next) — Series A, Series B - Beni Venture Capital (https://capitalatlas.ai/funds/beni-venture-capital) — Seed - Khosla Ventures (https://capitalatlas.ai/funds/khosla-ventures) — Series A, Series B - Lowercase Capital (https://capitalatlas.ai/funds/lowercase-capital) — Series A - Schooner Capital (https://capitalatlas.ai/funds/schooner-capital) — Series A, Series B - Starlight Ventures (https://capitalatlas.ai/funds/starlight-ventures) — Series A, Series B - Future Ventures — Series A, Series B - Moore Strategic Ventures (https://capitalatlas.ai/funds/moore-strategic-ventures) — Series A, Series B - Safar Partners (https://capitalatlas.ai/funds/safar-partners) — Series A, Series B - Temasek Holdings — Series A, Series B - Hostplus — Series A, Series B - F-Prime Capital (https://capitalatlas.ai/funds/f-prime-capital) — Series A - Equinor Ventures — Series A, Series B - Soros Fund Management — Series B - Tiger Global Management (https://capitalatlas.ai/funds/tiger-global-management) — Series B - GV (https://capitalatlas.ai/funds/gv) — Series B - Coatue Management (https://capitalatlas.ai/funds/coatue-management) — Series B - Salesforce, Inc. — Series B - DFJ Growth (https://capitalatlas.ai/funds/dfj-growth) — Series B - Senator Investment Group (https://capitalatlas.ai/funds/senator-investment-group) — Series B - Emerson Collective — Series B - JS Capital (https://capitalatlas.ai/funds/js-capital) — Series B - Lowercarbon Capital (https://capitalatlas.ai/funds/lowercarbon-capital) — Series B - FootPrint Coalition (https://capitalatlas.ai/funds/footprint-coalition) — Series B - HALJ Group — Series B - Time Ventures (https://capitalatlas.ai/funds/time-ventures) — Series B - Fine Structure Ventures (https://capitalatlas.ai/funds/fine-structure-ventures) — Series B - Jameel Investment Management Company (https://capitalatlas.ai/funds/jameel-investment-management-company) — Series B - Morgan Stanley Investment Management — Series B - Sumitomo Mitsui Trust Bank — Series B - Gates Foundation Trust — Series B - NTT — Series B - Development Bank of Japan (https://capitalatlas.ai/funds/development-bank-of-japan) — Series B - Kansai Electric Power — Series B - Sumitomo Mitsui Banking Corporation — Series B - FFA Private Bank — Series B - Mitsubishi Corporation — Series B - WOORI Venture Partners (https://capitalatlas.ai/funds/woori-venture-partners) — Series B - Mitsui & Co. — Series B - HOF Capital (https://capitalatlas.ai/funds/hof-capital) — Series B - Neva (https://capitalatlas.ai/funds/neva) — Series B - Galaxy Asset Management (https://capitalatlas.ai/funds/galaxy-asset-management) — Series B - Mitsui Fudosan — Series B - JGC Holdings — Series B - Eni — Series B - Planet First Partners (https://capitalatlas.ai/funds/planet-first-partners) — Series B - Mitsui O.S.K. Lines — Series B - Fujikura Components Ltd. — Series B - Brevan Howard US Investment Management — Series B - Gigascale Capital (https://capitalatlas.ai/funds/gigascale-capital) — Series B - NVentures — Series B - JERA Co., Inc. — Series B