# DEEP FISSION, INC. — Form D

DEEP FISSION, INC. of BERKELEY, CA, a company, filed a Form D exempt-offering notice with the SEC on 2025-09-24. The offering totals $120.0M. Industry: Other Energy.

## Offering

- Filed: 2025-09-24
- Form: D
- Accession: 0001231919-25-000236
- Industry: Other Energy
- Exemptions: 06b
- Total offering: $120.0M
- Remaining: $120.0M
- Investors: 83
- Date of first sale: 2025-09-05
- Security types: equity
- Revenue range: Decline to Disclose
- SEC file number: 021-558495

## Issuer

- Name: DEEP FISSION, INC.
- CIK: 0001918102
- Entity type: Corporation
- Jurisdiction: DELAWARE
- Incorporated: 2021
- Address: 2001 Addison Street, BERKELEY, CA, 94704
- Phone: (707) 400-0778

## Officers, directors & promoters (14)

| Name | Role | Location |
| --- | --- | --- |
| Elizabeth A Muller | Director | Berkeley, CA |
| Richard A Muller | Director | Berkeley, CA |
| Elizabeth A Muller | Executive Officer | Berkeley, CA |
| Richard A Muller | Executive Officer | Berkeley, CA |
| William Mark Schmitz | Executive Officer | Berkeley, CA |
| Jonathon S. Angell | Director | Berkeley, CA |
| Thomas S. Glanville | Director | Berkeley, CA |
| Leslie S. Goldman Tepper | Director | Berkeley, CA |
| Jon S. Gordon | Executive Officer | Berkeley, CA |
| Elizabeth A. Muller | Director | Berkeley, CA |
| Elizabeth A. Muller | Executive Officer | Berkeley, CA |
| Michael S. Brasel | Executive Officer | Berkeley, CA |
| Richard A. Muller | Executive Officer | Berkeley, CA |
| Blake S. Janover | Director | Berkeley, CA |

## Other filings by this issuer (2)

| Filed | Form | Offering | Sold |
| --- | --- | --- | --- |
| [2026-02-18](https://search.stillhousedata.com/formd/0001918102-26-000001) | D | $80.0M | $80.0M |
| [2025-09-23](https://search.stillhousedata.com/formd/0001918102-25-000004) | D | $31.8M | $30.0M |

## More

- [CIK 1918102 on SEC EDGAR (source of record)](https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=1918102&type=&dateb=&owner=include&count=40)
- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/formd/0001231919-25-000236.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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