# EDGAR Filing Document

**Accession Number:** 0001918102
**File Stem:** 9999999995-26-002042
**Filing Date:** 2026-6
**Character Count:** 1368
**Document Hash:** bef7f61b19110f766818d3356ee04dd7
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**9999999995-26-002042.hdr.sgml**: 20260618

**ACCESSION NUMBER**: 9999999995-26-002042

**CONFORMED SUBMISSION TYPE**: EFFECT

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260617

**DATE AS OF CHANGE**: 20260618

**EFFECTIVENESS DATE**: 20260617

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** DEEP FISSION, INC.
- **CENTRAL INDEX KEY:** 0001918102
- **STANDARD INDUSTRIAL CLASSIFICATION:** ELECTRIC SERVICES [4911]
- **ORGANIZATION NAME:** 01 Energy & Transportation
- **EIN:** 874265302
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** EFFECT
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-296043
- **FILM NUMBER:** 261100275

**BUSINESS ADDRESS:**
- **STREET 1:** 2831 GARBER STREET
- **CITY:** BERKELEY
- **STATE:** CA
- **ZIP:** 94705
- **BUSINESS PHONE:** (707) 400-0778

**MAIL ADDRESS:**
- **STREET 1:** 2831 GARBER STREET
- **CITY:** BERKELEY
- **STATE:** CA
- **ZIP:** 94705

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Surfside Acquisition Inc.
- **DATE OF NAME CHANGE:** 20220317

### UNITED STATES
### SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## Notice of Effectiveness

**Date:** June 17, 2026

**Time:** 16:00:00

**Form Type:** S-1

---

**CIK:** 0001918102

**Company Name:** DEEP FISSION, INC.

**File Number:** 333-296043