---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-26-046488"
form_type: "8-K"
ticker: "FISN"
cik: "0001918102"
company_name: "DEEP FISSION, INC."
filed_at: "2026-04-22T23:59:59+00:00"
generated_at: "2026-05-15T04:56:27.004602+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# Deep Fission confidentially submits draft S-1 for proposed IPO of common stock

## Summary
- Confidential submission of Form S-1 to SEC for a proposed public offering of common stock.
- Number of shares and price range not yet determined; offering subject to market conditions.
- Deep Fission develops small modular pressurized water reactors installed one mile underground.

## SEC filing metadata
- accession: 0001104659-26-046488
- form_type: 8-K
- ticker: FISN
- cik: 0001918102
- company_name: DEEP FISSION, INC.
- filed_at: 2026-04-22T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1918102/000110465926046488/0001104659-26-046488-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1918102/000110465926046488/tm2612289d1_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-26-046488
- JSON: https://secwatch.observer/filing/0001104659-26-046488.json
- Plain text: https://secwatch.observer/filing/0001104659-26-046488.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.