T3 Defense Inc.

(Former name or former address, if changed since last report)

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Item 1.01 Entry into a Material Definitive Agreement.

On October 26, 2026, T3 Defense Inc., a Delaware corporation (the “Company”), entered into a Stock Purchase Agreement (the “Purchase Agreement”) with KeepZone AI Inc., a Delaware corporation (“KeepZone”), and Nexera Technologies Ltd., an Israeli company (“Seller”), pursuant to which the Company agreed to acquire from Seller all of the issued and outstanding shares of KeepZone. The aggregate purchase price is $1,000,000, payable at closing in shares of the Company’s common stock, par value $0.0001 per share (the “Common Stock”), and, to the extent required to comply with a 4.99% beneficial ownership limitation, pre-funded warrants to purchase Common Stock (the “Pre-Funded Warrants”). The number of shares issued will be determined using the average closing price of the Common Stock on Nasdaq for the five trading days immediately preceding the closing date, subject to adjustment for stock splits, combinations and similar events. The Pre-Funded Warrants, if issued, will have an exercise price of $0.0001 per share and will be immediately exercisable, subject to the applicable beneficial ownership limitation. Prior to closing, Seller is expected to cause KeepZone to transfer its available cash to Seller and settle, release or cancel specified indebtedness and intercompany balances, without adjustment to the purchase price.

KeepZone operates in the global Homeland Security sector, delivering comprehensive, multi-layered security ecosystems for critical infrastructure worldwide. Its business model is to facilitate the adoption of HLS technologies by acting as an integrator, distributor and market channel for defense and security solutions. KeepZone currently has several non-exclusive reseller agreements.

Seller is entitled to a cash earn-out equal to 50% of the Company’s net profit (as defined in the Agreement) for 24 months after closing, up to a maximum of $5,000,000. Moreover, the Company is not obligated to file a resale registration statement covering the securities issued as consideration, although it may elect to do so. In addition, the Purchase Agreement provides that, if on the 181st day following closing Seller continues to hold shares of Common Stock, no resale registration statement covering such shares is effective, and the Nasdaq trading price of Common Stock is below the closing-date reference price, the Company will be required to issue additional shares of Common Stock to bring the total market value of the consideration shares issued to the Seller to $1,000,000.

Completion of the acquisition is subject to satisfaction or waiver of customary closing conditions, including applicable third-party consents and regulatory and Nasdaq requirements, including any required Listing of Additional Shares notification. Closing is expected to occur on the second business day after satisfaction or waiver of the applicable conditions.

Either the Company or the Seller may terminate the Purchase Agreement if the closing has not occurred within 60 days after signing, subject to certain exceptions.

The foregoing description of the Purchase Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Purchase Agreement, filed as Exhibit 10.58 to this Current Report on Form 8-K and incorporated herein by reference.

Item 7.01 Regulation FD Disclosure.

On October 27, 2026, the Company issued a press release announcing the acquisition of the 100% interest in KeepZone. The press release is attached to this Report as Exhibit 99.1 and is incorporated herein by reference.

The information in this Item 7.01 of this Report, including Exhibit 99.1 attached hereto, is being furnished and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), nor shall it be deemed incorporated by reference in any filing of ours under the Securities Act, or the Exchange Act, whether made before or after the date hereof, except as shall be expressly set forth by specific reference to this Report in such filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits