Filed Pursuant to Rule 424(b)(3)
Registration No. 333-267375

PROSPECTUS SUPPLEMENT NO. 9
(to prospectus dated April 18, 2023)

NAUTICUS ROBOTICS, INC.

8,275,000 Shares of Common Stock

Up to 8,625,000 Shares of Common Stock Underlying Public Warrants to Purchase Common Stock

Up to 7,175,000 Shares of Common Stock Underlying Private Warrants to Purchase Common Stock

Up to 2,922,425 Shares of Common Stock Underlying Securities Purchase Agreement Warrants to Purchase Common Stock

Up to 2,922,425 Shares of Common Stock Underlying Convertible Debentures

This prospectus supplement is being filed to update and supplement the information contained in the prospectus dated April 18, 2023 (the “Prospectus”), with the information contained in our Current Report on Form 8-K filed with the Securities and Exchange Commission (the “SEC”) on December 1, 2023 (the “Current Report”). Accordingly, we have attached the Current Report to this prospectus supplement.

The Prospectus and this prospectus supplement relate to the offer and sale by us of (i) 862,500 shares of common stock, par value $0.0001 per share (“Common Stock”), of Nauticus Robotics, Inc. (the “Company”) which were issued upon the conversion of the rights to receive one twentieth (1/20) of one share of Common Stock (the “Right Shares”) in connection with the closing of the Business Combination (defined below), (2) 8,625,000 shares of Common Stock (the “Public Warrant Shares”) issuable upon the exercise of 8,625,000 redeemable warrants, which are exercisable at a price of $11.50 per share (the “Public Warrants”) and (3) 7,175,000 shares of Common Stock (the “Private Warrant Shares”) issuable upon the exercise of 7,175,000 redeemable warrants, purchased by CleanTech Sponsor I LLC and CleanTech Investments, LLC (together, the “Co-sponsors”) at a price of $1.00 per Private Warrant pursuant to a subscription agreement entered into in connection with CLAQ’s (defined below) initial public offering (“IPO”), which are exercisable at a price of $ 11.50 per share (the “Private Warrants”).

The Prospectus and this prospectus supplement also relate to the resale from time to time by the selling securityholders named in the Prospectus or their permitted transferees (the “Selling Securityholders”) of (i) 4,312,500 shares of Common Stock (the “Founder Shares”) that were issued to the Co- sponsors in conjunction with the IPO at a purchase price equivalent to approximately $0.00058 per Founder Share and subsequently converted upon the closing of the Business Combination and (ii) 3,100,000 shares of Common Stock purchased by certain Selling Securityholders at a price of $10.00 per share of Common Stock, and issued pursuant to the terms of certain subscription agreements entered into in connection with the Business Combination pursuant to the Merger Agreement (the “Merger Agreement,” and together with the other agreements and transactions contemplated thereby, the “Business Combination”) by and among CleanTech Acquisition Corp. (“CleanTech” or “CLAQ”), Nauticus Robotics Holdings, Inc. (formerly known as “Houston Mechatronics, Inc.”), a Texas corporation (“Nauticus Robotics Holdings”), and CleanTech Merger Sub, Inc. (“Merger Sub”), a wholly- owned subsidiary of CleanTech. Pursuant to the Merger Agreement, in connection with the consummation of the Business Combination Merger Sub merged with and into Nauticus Robotics Holdings, with Nauticus Robotics Holdings surviving the merger as a wholly owned subsidiary of the Company, and the Company was renamed “Nauticus Robotics, Inc.”

Further, the Prospectus and this prospectus relate to the offer and sale by us of (i) 2,922,425 shares of Common Stock (the “SPA Warrant Shares”) which have been or may be issued from time to time upon the exercise of 2,922,425 warrants that were issued to certain Selling Securityholders (the “SPA Investors”) pursuant to the SPA (the “SPA Warrants”) and (ii) 2,922,425 shares of Common Stock (the “Debenture Shares” and together with the SPA Warrant Shares, the “SPA Shares”) issuable upon the conversion of the debentures (the “Debentures”) that were purchased by certain Selling Securityholders pursuant to the SPA. Pursuant to the Securities Purchase Agreement by and among the Company, Nauticus Robotics Holdings, and the SPA Investors (the “SPA”), the SPA Investors subscribed for Debentures in an aggregate principal amount of $36,530,320. In exchange for such subscriptions, Nauticus delivered to such Selling Securityholders (i) a Debenture with a principal amount equal to such Selling Securityholder’s subscription amount and (ii) SPA Warrants.

This prospectus supplement updates and supplements the information in the Prospectus and is not complete without, any may not be delivered or utilized except in combination with, the Prospectus, including any amendments or supplements thereto. This prospectus supplement should be read in conjunction with the Prospectus and if there is any inconsistency between the information in the Prospectus and this prospectus supplement, you should rely on the information in this prospectus supplement.

Our Common Stock is listed on the Nasdaq Stock Market LLC under the symbol “KITT.” On December 1, 2023, the closing price for our Common Stock was $1.10 per share.

We are an “emerging growth company” as defined under the federal securities laws and, as such, have elected to comply with certain reduced public company reporting requirements.

Investing in our securities involves risks that are described in the “Risk Factors” section beginning on page 12 of the Prospectus. Neither the SEC nor any state securities commission has approved or disapproved of the securities to be issued under the Prospectus or determined if the Prospectus or this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is December 1, 2023.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

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

Date of Report (Date of earliest event reported): November 30, 2023

NAUTICUS ROBOTICS, INC.

(Exact name of registrant as specified in its charter)

17146 Feathercraft Lane, Suite 450, Webster, TX 77598

(Address of principal executive offices, including zip code)

Registrant’s telephone number, including area code: (281) 942-9069

Not Applicable

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

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

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

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☒

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. ☐

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officer; Compensatory Arrangements of Certain Officers

Removal of Officers

On November 30, 2023, the Board of Directors (the “Board”) of Nauticus Robotics, Inc. (the “Company”) removed Rangan Padmanabhan, the Company’s Chief Financial Officer and principal financial officer, and M. Dilshad Kasmani, the Company’s Chief Legal and Administrative Officer, as officers of the Company. The Board views these removals as “terminations other than for cause” under their respective employment agreements. The Board thanks Mr. Padmanabhan and Mr. Kasmani for their work at the Company and wishes them the best in their future endeavors.

Appointment of Interim Chief Financial Officer

On December 1, 2023, the Board appointed Victoria Hay as the Interim Chief Financial Officer and principal financial officer of the Company. Mrs. Hay, 40, has been the co-owner and President of Flexible Consulting, LLC, a financial and accounting consulting firm, since May 2021. In her capacity as President of Flexible Consulting, LLC, Mrs. Hay has acted as a financial and accounting advisor for numerous companies, including acting as contracted Chief Financial Officer of Enovate, an AI company focused on the oil and gas sector. Prior to her time at Flexible Consulting, LLC Mrs. Hay was at Weatherford International plc (NASDAQ: WFRD) from 2008 to May 2021 in accounting and finance roles of increasing seniority, most recently as the Senior Director – Global Accounting and Reporting Services. Mrs. Hay began her career as a finance analyst with Morgan Stanley. Mrs. Hay is a CIMA chartered accountant and has a BSC(Hon) in Biotechnology with a Management emphasis from Edinburgh University.

Mrs. Hay, through Flexible Consulting, LLC, will receive cash compensation of $30,000 per month and up to $1,000 per month of expense reimbursement. Mrs. Hay will also be granted 40,000 restricted stock units of the Company that will vest at the earlier of Mrs. Hay’s departure and one year from the date of grant. There is no arrangement or understanding between Mrs. Hay and any other person pursuant to which she was to be selected as an officer and there is no family relationship between Mrs. Hay and any of the Company’s directors, executive officers, or any person nominated or chosen by the Company to become a director or executive officer.

Since January 2023, the Company has engaged Flexible Consulting, LLC, where Mrs. Hay is President and which she co-owns, to provide it with accounting and finance services relating to its quarterly reporting and mergers/acquisition activity. The total value of services provided by Flexible Consulting, LLC to the Company during this engagement is approximately $446,000.

Change to Board Compensation

On November 30, 2023, the Board approved a change to the compensation structure of the non-executive directors of the Board pursuant to which the non-executive directors may elect to receive cash compensation in an equivalent amount of restricted stock units until the Company’s 2024 annual meeting of stockholders. Any restricted stock units that are granted in respect of such election will vest on the earliest of (1) the 2024 annual meeting of stockholders, (2) the departure of the applicable non-executive director and (3) one year from the date of grant.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.