Nauticus Robotics, Inc.

Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. On July 20, 2026, the Company issued an Original Issue Discount Senior Secured Convertible Debenture Due 2026, in the aggregate principal amount of $1,500,000.00 (the “Additional Note”), to an institutional investor ("Investor"), which is convertible into 197,369 shares of common stock of the Company calculated at a conversion price of $7.60. The Additional Note was issued pursuant to the securities purchase agreement dated as of November 4, 2024 (the “Securities Purchase Agreement”) with certain investors including Investor, as previously described in the Company's Current Report on Form 8-K filed with the Securities Exchange Commission on November 5, 2024 (the “November 5 Form 8-K”). The Additional Note has the same terms as the Notes under the Securities Purchase Agreement as described in the November 5 Form 8-K and will mature on September 9, 2026 or such earlier date as is required or permitted to be repaid under such Additional Note. The foregoing description of the transaction described in this Item 2.03 does not purport to be completed and is qualified in its entirety by reference to the complete text of the Additional Note, a copy of which was attached to the November 5 Form 8-K as Exhibit 10.3.

Item 3.02 Unregistered Sales of Equity Securities . The information set forth under Item 2.03 of this Current Report is incorporated herein by reference. The issuance of the Additional Note was not registered under the Securities Act in reliance on the exemption provided by Section 4(a)(2) of the Securities Act and Rule 506 of Regulation D promulgated thereunder, or under any state securities laws.