Nukkleus Inc.

As filed with the Securities and Exchange Commission on December 17, 2025.

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORMS-1

REGISTRATION STATEMENT

UNDER THE SECURITIES ACT OF 1933

Nukkleus Inc.

(Exact name of registrant as specified in its charter)

575 Fifth Ave., 14th Floor

New York, New York 10017

(212) 791-4663

(Address, including zip code, and telephone number, including area code, of Registrant’s principal executive offices)

Menachem Shalom

Chief Executive Officer

575 Fifth Ave., 14th Floor

New York, New York 10017

(212) 791-4663

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Robert Cohen

McDermott Will & Schulte LLP

333 SE 2nd Avenue, Suite 4500

Miami, Florida 33131

(212) 547-5885

Approximate date of commencement of proposed sale to the public:

As soon as practicable after the effective date hereof.

If any securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, 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 7(a)(2)(B) of the Securities Act.☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission acting pursuant to said section 8(a), may determine.

The information in this prospectus is not complete and may be changed. The selling stockholders may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state or jurisdiction where the offer or sale is not permitted.

PRELIMINARY PROSPECTUS

SUBJECT TO COMPLETION, DATED DECEMBER 17, 2025

13,090,500 Shares of Common Stock

This prospectus relates to the resale from time to time by the selling stockholders named in this prospectus, including their transferees, pledgees or donees or their respective successors (collectively, the “Selling Stockholders”), of up to 13,090,500 shares (the “Shares”) of the common stock, par value $0.0001 per share (the “Common Stock”), of Nukkleus Inc., a Delaware corporation (the “Company” or “Nukkleus”), which consists of up to 5,112,000 Shares (the “Conversion Shares”) issuable upon the conversion of the outstanding shares of our Series A Convertible Preferred Stock, par value $0.0001 per share (the “Series A Preferred Stock”), and (ii) up to 7,978,500 Shares (the “Warrant Shares”) issuable upon the exercise of common warrants (the “Common Warrants”). The shares of Series A Preferred Stock and the Common Warrants were purchased by certain accredited investors in a private placement (the “September 2025 Private Placement”) pursuant to the Securities Purchase Agreement, dated September 4, 2025, by and between the Company and such investors (the “Securities Purchase Agreement”).

Each share of Series A Preferred Stock has a stated value of $50,000 (the “Stated Value”) and was initially convertible into 10,224 Conversion Shares (or pre-funded warrants in lieu thereof (the “Pre-Funded Warrants”)), calculated by dividing the Stated Value by the initial conversion price equal to $4.89 per share of Series A Preferred Stock (the “Initial Conversion Price”). Upon the Company obtaining stockholder approval of the transactions contemplated by the Securities Purchase Agreement and the related agreements at the special meeting of stockholders held on December 16, 2025 (the “Special Meeting”), the Initial Conversion Price was adjusted to the lower of (i) $4.72 per share and (ii) the price per share upon the earlier of (A) effectiveness of the registration statement of which this prospectus is a part or (B) upon applicability of Rule 144, as such Rule may be amended or interpreted from time to time (“Rule 144”), under the Securities Act of 1933, as amended (the “Securities Act”), as it relates to the sale of the Conversion Shares. The Initial Conversion Price is subject to further adjustment upon stock splits, distributions, reorganizations, reclassifications, change of control and the like, and is also subject to price-based anti-dilution adjustments for subsequent offerings made by the Company while the Series A Preferred Stock remains outstanding (subject to certain exempt issuances). Assuming an Initial Conversion Price of $4.72 per share, each share of Series A Preferred Stock is convertible into 10,593 shares of Common Stock (or pre-funded warrants in lieu thereof). We are registering for resale a number of Shares equal to 250% of the maximum number of Conversion Shares issuable as of the date of the Securities Purchase Agreement. The shares of Series A Preferred Stock are subject to a blocker provision (the “Preferred Blocker”), which restricts the conversion of the Series A Preferred Stock if, as a result of such conversion, the holder, together with its affiliates and any other person whose beneficial ownership of Common Stock would be aggregated with the holder’s for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), would beneficially own in excess of 9.9% of our then issued and outstanding shares of Common Stock (including the shares of Common Stock issuable upon such exercise).

Each Common Warrant is exercisable for one Warrant Share at an initial exercise price of $5.405 per share, subject to adjustment for stock splits, distributions and the like (the “Initial Exercise Price”). The Initial Exercise Price is subject to price-based anti-dilution adjustments for subsequent offerings made by the Company while the Common Warrants remain outstanding (subject to certain exempt issuances). The holder of the Common Warrants may exchange the Common Warrants on a cashless basis for a number of shares of Common Stock determined by multiplying the total number of Warrant Shares with respect to which the Common Warrant is then being exercised by the Black Scholes Value (as defined in the Common Warrant) divided by the lower of the two closing bid prices of the Common Stock in the two days prior the time of such exercise, but in any event not less than $0.01 (as may be adjusted for stock dividends, subdivisions, or combinations and the like). We are registering for resale a number of Shares equal to 250% of the maximum number of Warrant Shares issuable as of the date of the Securities Purchase Agreement without giving effect to the cashless exchange of the Common Warrants. The Common Warrants are subject to a blocker provision (the “Warrant Blocker” and, together with the Preferred Blocker, the “Blockers”), which restricts the exercise of a Common Warrant if, as a result of such exercise, the holder, together with its affiliates and any other person whose beneficial ownership of Common Stock would be aggregated with the holder’s for purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 9.9% of our then issued and outstanding shares of Common Stock (including the shares of Common Stock issuable upon such exercise).

The Shares being registered for resale represent a considerable percentage of our public float, and the sales of such Shares, or the perception that these sales could occur, could cause the market price of the Common Stock to decline significantly. In addition, we are not selling any shares of Common Stock under this prospectus and will not receive any of the proceeds from the sale of Shares by the Selling Stockholders. We are paying the cost of registering the Shares as well as various related expenses. The Selling Stockholders are responsible for all selling commissions, transfer taxes and other costs related to the offer and sale of their Shares. We will, however, receive the net proceeds of any Common Warrants exercised for cash. For a description of the transaction pursuant to which this resale registration statement relates, please see “Prospectus Summary – The Offering.”

The Selling Stockholders may sell the Shares at fixed prices, at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices. The Selling Stockholders may sell the Shares to or through underwriters, broker-dealers or agents, who may receive compensation in the form of discounts, concessions or commissions from the Selling Stockholders, the purchasers of the Shares, or both.

Our Common Stock is presently listed on the Nasdaq Global Market (“Nasdaq”) under the symbol “NUKK.” The closing price for our Common Stock on December 16, 2025, as reported by Nasdaq, was $5.12 per share.

We are an “emerging growth company” as the term is used in the Jumpstart Our Business Startups Act of 2012 and, as such, have elected to comply with certain reduced public company reporting requirements for this prospectus and future filings.

Investing in our securities involves a high degree of risk. You should carefully consider the risks and uncertainties described under the heading“Risk Factors” beginning on page 8** of this prospectus before making a decision to purchase our securities.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

The date of this prospectus is , 2025

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