Form: EFFECT

Notice of Effectiveness

February 5, 2026

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

Notice of Effectiveness

Effectiveness Date: February 5, 2026 4:00 P.M.
Form: S-1
CIK: 0001918102
Company Name: DEEP FISSION, INC.
File Number: 333-290438