T3 Defense Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31,2025

or

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

001-39341

Commission file number

(Exact name of registrant as specified in its charter)

212-791-4663

Registrant’s telephone number, including area code

Securities registered pursuant to Section 12(b) of the Act:

Securities registered under Section 12(g) of the Exchange Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☐No ☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐No ☒

Indicate by check mark whether the registrant (1) has filed all reports required by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. ☒Yes ☐ No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such fi les). ☒Yes ☐ No

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No☒

The aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant was approximately $40,329,000 as of June 30, 2025, based upon the closing stock price $10.93 per share reported for such date.

State the number of shares outstanding of each of the issuer’s classes of common equity, as of the latest practicable date.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This report contains forward-looking statements that involve a number of risks and uncertainties. Although our forward-looking statements reflect the good faith judgment of our management, these statements can be based only on facts and factors of which we are currently aware. Consequently, forward-looking statements are inherently subject to risks and uncertainties. Actual results and outcomes may differ materially from results and outcomes discussed in the forward-looking statements.

Forward-looking statements can be identified by the use of forward-looking words such as “may,” “will,” “should,” “anticipate,” “believe,” “expect,” “plan,” “future,” “intend,” “could,” “estimate,” “predict,” “hope,” “potential,” “continue,” or the negative of these terms or other similar expressions. These statements include, but are not limited to, statements under the captions “Risk Factors,” “Management’s Discussion and Analysis or Plan of Operation” and “Description of Business,” as well as other sections in this report. Such forward-looking statements are based on our management’s current plans and expectations and are subject to risks, uncertainties and changes in plans that may cause actual results to differ materially from those anticipated in the forward-looking statements. You should be aware that, as a result of any of these factors materializing, the trading price of our common stock may decline. These factors include, but are not limited to, the following:

The cautionary statements made in this annual report are intended to be applicable to all related forward-looking statements wherever they may appear in this report.

We urge you not to place undue reliance on these forward-looking statements, which speak only as of the date of this report. We undertake no obligation to publicly update any forward looking-statements, whether as a result of new information, future events or otherwise.

All references in this Form 10-K that refer to the “Company”, “T3 Defense”, “we,” “us” or “our” refer to T3 Defense Inc. f/k/a Nukkleus Inc. and its consolidated subsidiaries.

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