Deep Fission
NASDAQ: FISNBerkeley, US · Founded 2021 · Delaware corporation · 75 employees on LinkedIn · 5 known investors
Deep Fission develops a nuclear reactor deployment system that places a pressurized water reactor about a mile underground in a deep borehole, using hydrostatic pressure for operating conditions and geothermal-style energy transfer to surface turbines. The company aims to reduce the cost and complexity of surface infrastructure and has signed letters of intent for power site partnerships totaling 18.5 GW.
Founders & leadership
Deep Fission was founded in 2021 by Richard Muller and Elizabeth A. Muller.
RM
Richard MullerCo-founder
EA
Elizabeth A. MullerCo-founder
WM
William Mark SchmitzExecutive
Investors · 5
Capital FactoryAustin
Blue Owl CapitalreportedNew York
Deep FuturereportedSeattlevia Pablos Holman · inferred
Also in the syndicate · 2
EE HoldingsMontrose Capital
Funding
SEC filings, press & company announcements$150M disclosed across 3 of 4 rounds · 2025–2026
- $40MraisedJun 2026Source ↗
▶$80MraisedFeb 2026 · 223 investors · Other EnergyRule 506(b)
▶$80MraisedFeb 2026 · 223 investors · Other Energy
Rule 506(b)Officers, directors & promoters on the filing
- Jonathon AngellDirector
- William Mark SchmitzExecutive Officer
- Thomas S. GlanvilleDirector
- Leslie Goldman TepperDirector
- Jon GordonExecutive Officer
- Elizabeth A. MullerExecutive Officer, Director
- Michael BraselExecutive Officer
- Richard MullerExecutive Officer
- Blake JanoverDirector
- Offering amount
- $80M
- Amount sold
- $80M
- Minimum investment
- $10K
- Sales commissions
- $3.6M
- Placement agents
- The Benchmark Company, LLC, PHX Financial, Inc., d/b/a Phoenix Financial Services, Seaport Global Securities LLC, Network 1 Financial Securities, Inc.
- First sale
- Feb 2026
- Incorporated
- Corporation, Delaware, 2021
- Federal exemptions
- 06b
▶$120MofferedSep 2025 · 83 investors · Other EnergyRule 506(b)
▶$120MofferedSep 2025 · 83 investors · Other Energy
Rule 506(b)Officers, directors & promoters on the filing
- Elizabeth A. MullerExecutive Officer, Director
- William Mark SchmitzExecutive Officer
- Richard MullerExecutive Officer, Director
- Offering amount
- $120M
- First sale
- Sep 2025
- Incorporated
- Corporation, Delaware, 2021
- Federal exemptions
- 06b
▶$30MraisedSep 2025 · 100 investors · Other EnergyRule 506(b)
▶$30MraisedSep 2025 · 100 investors · Other Energy
Rule 506(b)Officers, directors & promoters on the filing
- Richard MullerExecutive Officer, Director
- William Mark SchmitzExecutive Officer
- Elizabeth A. MullerExecutive Officer, Director
- Offering amount
- $31.8M
- Amount sold
- $30M
- Sales commissions
- $2.1M
- Placement agents
- Seaport Global Securities LLC, Phoenix Financial Services, Network 1 Financial Securities, Inc., The Benchmark Company, LLC, Dinosaur Financial Group, L.L.C.
- First sale
- Sep 2025
- Incorporated
- Corporation, Delaware, 2021
- Federal exemptions
- 06b
Source: SEC EDGAR Form D. Amounts as filed; amended filings shown once at their latest values.
In the news
🌎 Micro-reactor funding goes macro #309ctvc.co · Aug 2026Frequently asked questions
- What does Deep Fission do?
- Deep Fission develops a nuclear reactor deployment system that places a pressurized water reactor about a mile underground in a deep borehole, using hydrostatic pressure for operating conditions and geothermal-style energy transfer to surface turbines. The company aims to reduce the cost and complexity of surface infrastructure and has signed letters of intent for power site partnerships totaling 18.5 GW.
- Who founded Deep Fission?
- Deep Fission was founded by Richard Muller, Elizabeth A. Muller in 2021.
- Who are Deep Fission's investors?
- Deep Fission's investors include Capital Factory, Blue Owl Capital, Deep Future.
- How much funding has Deep Fission raised?
- Deep Fission has disclosed $150M raised across 3 of its 4 known rounds.
- Where is Deep Fission headquartered?
- Deep Fission is headquartered in Berkeley, US.