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FISNNasdaqElectric ServicesFiscal year ends December 31

DEEP FISSION, INC.

Financials through Q2 FY2026, quarter ended Jun 30, 2026Last filing: 10-Q on Aug 3, 2026
$3.66+0.21 (+6.09%)

Close on Oct 19, 2026

Market cap
$201.66M
P/E (TTM)
–
Dividend yield
–

About Deep Fission

Electric Services, SIC 4911

Deep Fission is a nuclear energy technology company that develops small modular reactors known as Gravity Reactors. The system integrates established pressurized water reactor technology into deep boreholes roughly one mile underground, relying on hydrostatic pressure from water columns for cooling and operational pressure. The company plans to deploy standalone units or borehole clusters producing electrical power for high-demand users, with a primary commercial focus on hyperscale data centers, as well as utilities, industrial operators, and defense facilities. Its planned business model spans project equity participation from electricity sales, deployment services, technology licensing, and maintenance operations.

The development-stage company operates an initial field development site on approximately 100 leased acres in Parsons, Kansas, where it conducts geological surveys and has drilled a deep data acquisition well. In addition to candidate commercial sites under preliminary evaluation across Kansas, Texas, Utah, and internationally, the enterprise maintains its corporate presence in the United States, though the text does not identify a specific headquarters location.

Summary of the business section of Deep Fission's latest annual report, written by StockData.

Company profile

Company

Legal name
DEEP FISSION, INC.
Founded
2023
Headquarters
Berkeley, CA
Address
2831 Garber Street 94705
Phone
(707) 400-0778
Employees
51, Dec 31, 2025
Industry
Electric Services
Incorporated in
Delaware
Fiscal year ends
December 31
Auditor
GRANT THORNTON LLP, Dallas, Texas

Stock & identifiers

Ticker
FISN
Exchange
Nasdaq
IPO date
Jun 18, 2026
Shares outstanding
59M, Jul 27, 2026
Filer category
<br>Emerging growth company
Stock splits
1-for-1.5 reverse, Apr 15, 2026
SEC CIK
1918102
CUSIP
243927100
ISIN
US2439271006
EIN
87-4265302

Executives and directors

Officers and directors who filed ownership reports (Forms 3, 4, 5) in the last two years

NamePositionShares owned
Ian Seth JacobsPresident, CEO, CFO, Secretary, Director275,000
Richard MullerChief Technology Officer5,196,426
Jonathan H. GordonGeneral Counsel–
Elizabeth MullerChief Executive Officer5,607,306
William Mark SchmitzChief Financial Officer103,928
Mark Wayne PeresChief Nuclear Officer86,607
Michael Allen BraselChief Operating Officer–
Thomas S. GlanvilleDirector–
Jonathon AngellDirector324,517
Tepper Leslie GoldmanDirector133,996
Blake JanoverDirector–

Employees

Headcount reported in annual reports

“As of the date of this Annual Report, we had 51 employees and 9 consultants.”

Corporate history

Events identified from SEC filings

DateEventDetails
Jun 18, 2026IPOInitial public offering priced (424B4 prospectus)
May 28, 2026ListingRegistration of securities on an exchange (Form 8-A)
Mar 31, 2026Late filingNotification of late filing
Mar 5, 2026Auditor changeChange in certifying accountant (8-K Item 4.01)
Sep 11, 2025Acquisition / saleCompletion of acquisition or disposition of assets (8-K Item 2.01)
Sep 11, 2025Auditor changeChange in certifying accountant (8-K Item 4.01)
Sep 8, 2025Name changeName changed from Surfside Acquisition Inc. to DEEP FISSION, INC.
Jul 28, 2022Auditor changeChange in certifying accountant (8-K Item 4.01)
Jul 19, 2022Auditor changeChange in certifying accountant (8-K Item 4.01)