IPO Journey
DEEP FISSION, INC.
IPO Date: June 18, 2026 · 10 filings tracked
Final Offer Terms
Ticker
FISN
Exchange
Nasdaq Global Market
Offer Price
$16.00
Shares Offered
2,500,000
Estimated Proceeds
$40.0M
Expected Listing
June 22, 2026
Underwriters
Led by Benchmark, a Stone X Company, Seaport Global Securities
Maxim Group LLC
Filing Timeline
1
S-1
September 22, 2025
- Innovative micro-nuclear reactor design utilizing deep borehole placement for natural shielding and cooling.
- Targeting high-demand sectors including industrial sites, data centers, and urban power grids.
2
S-1/A
September 24, 2025
- Innovative modular nuclear reactor design utilizing underwater pressure for natural cooling.
- Significant potential for scalable, carbon-free energy solutions for factories and cities.
3
S-1/A
December 1, 2025
- Innovative 'Gravity Reactor' technology utilizes deep-borehole geology for nuclear containment.
- Modular, plug-and-play design targeting high-demand sectors like AI data centers.
4
S-1/A
December 30, 2025
- Innovative 'Gravity Reactor' design places modular nuclear reactors one mile underground.
- Targeting high-growth energy sectors, specifically massive AI data centers.
5
S-1/A
January 27, 2026
- Developing innovative 'Gravity Reactors' for deep-borehole nuclear power
- Targeting high-demand markets like AI data centers and manufacturing
6
S-1
February 17, 2026
- Innovative 'Gravity Reactor' design utilizes deep-borehole placement to eliminate expensive surface-level containment infrastructure.
- Selected by the U.S. Department of Energy (DOE) for the Nuclear Reactor Pilot Program in August 2025.
7
S-1/A
April 21, 2026
- Innovative 'Gravity Reactor' design places nuclear power one mile underground for natural cooling and safety.
- Modular 15-megawatt units designed for factory production and scalable deployment.
8
S-1
May 20, 2026
- Innovative 'Gravity Reactor' design submerges modular nuclear reactors a mile underground for enhanced safety and natural cooling.
- Strategic alignment with the AI boom, targeting the massive, constant power needs of hyperscale data centers.
9
S-1/A
June 10, 2026
- Innovative 'Gravity Reactor' technology utilizes deep boreholes for modular, carbon-free energy.
- Strategic partnerships secured with industry leaders Blue Owl, Halliburton, and Urenco.
Changes from previous filing
- ▸ Ticker symbol: FISN
- ▸ Exchange: Nasdaq Global Market
- ▸ Expected offer range: $16.0 – $18.0 per share
- ▸ Shares offered: 2,500,000
- ▸ Estimated proceeds: $40M
- ▸ Underwriters: Benchmark, a Stone X Company, Seaport Global Securities, Maxim Group LLC
424B4
Final Pricing
June 18, 2026
- Innovative 'Gravity Reactor' design places nuclear power a mile underground for enhanced safety and security.
- Utilizes proven Pressurized Water Reactor technology, reducing the risks associated with experimental nuclear physics.
Changes from previous filing
- ▸ Price range removed
- ▸ Final offer price: $16.0 per share
Disclaimer: AI-generated analysis for informational purposes only. Not financial advice. Always conduct your own research.