Nuclear Startup Deep Fission Files $157M Nasdaq IPO as Reactor Date Slips
WinBuzzer
Last updated: May 25, 2026
Nuclear energy startup Deep Fission is attempting a public offering of approximately $157 million on the Nasdaq, aiming for a $1.66 billion valuation. The company is developing an unconventional underground small modular reactor (SMR) design, but faces significant financial and developmental hurdles.
- Deep Fission's public offering aims to raise capital for its novel underground reactor concept, which uses geological depth and water pressure for safety. The company is pursuing a $157 million offering of common stock on the Nasdaq, with an offered price per share between $24 and $26, and an option for additional shares.
- Despite the IPO attempt, auditors have raised concerns about Deep Fission's ability to continue as a going concern, warning it may run out of cash within a year if the offering does not close successfully. The company's accumulated deficit has grown significantly, and its cash burn rate has accelerated.
- Key milestones, such as switching on its first underground reactor and achieving criticality, have been delayed, with no new dates set. The company's initial public listing attempt via a reverse merger with a shell company in 2025 did not result in publicly traded stock.
- The underground reactor design, the "Gravity Reactor," is conceptual and has not yet been built or licensed. While drilling has commenced at a test site, the current depth is only a fraction of the planned operating depth, leaving critical engineering assumptions unproven.
