Deep Fission, Inc. SEC filings FISN
Deep Fission, Inc. has 123 filings in SEC EDGAR's recent list, going back to Mar 21, 2022. Its latest annual report, Form 10-K, was filed on Apr 15, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Nov 4, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Oct 20, 2026 (regulation fd disclosure). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| S-3 | Shelf registration | Nov 4, 2026 | — |
| S-8 | Employee stock plan registration | Jul 20, 2026 | — |
| 424B4 | Prospectus | Jun 18, 2026 | — |
| S-1/A | Amended registration statement | Jun 10, 2026 | — |
| S-1 | Registration statement | May 20, 2026 | — |
| 424B3 | Prospectus | May 1, 2026 | — |
| 424B3 | Prospectus | May 1, 2026 | — |
| S-1/A | Amended registration statement | Apr 21, 2026 | — |
| POS AM | Filing | Apr 21, 2026 | — |
| S-1 | Registration statement | Feb 17, 2026 | — |
| 424B3 | Prospectus | Feb 10, 2026 | — |
| 424B5 | Prospectus supplement | Feb 6, 2026 | — |
| S-1/A | Amended registration statement | Jan 27, 2026 | — |
| S-1/A | Amended registration statement | Dec 30, 2025 | — |
| S-1/A | Amended registration statement | Dec 1, 2025 | — |
| S-1/A | Amended registration statement | Sep 24, 2025 | — |
| S-1 | Registration statement | Sep 22, 2025 | — |
Showing 17 filings. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
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Company profile
- Industry
- Electric Services (SIC 4911)
- Listed as
- FISN (Nasdaq)
- Fiscal year ends
- December 31
- Incorporated in
- DE
- Headquarters
- Berkeley, CA
- SEC filer status
- Non-accelerated filer, Smaller reporting company, Emerging growth company
- SEC CIK
- 1918102
- Former names
- Surfside Acquisition Inc. (until Sep 8, 2025)
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Source: SEC EDGAR filings. This is company-reported data, not investment advice.