Form 424B3 - Prospectus [Rule 424(b)(3)]

Filed Pursuant to Rule 424(b)(3)

Registration No. 333-276877

PROSPECTUS SUPPLEMENT NO. 3

(TO PROSPECTUS DATED FEBRUARY 5, 2024)

This prospectus supplement updates and supplements the prospectus dated February 5, 2024 (the “Prospectus”), which forms a part of our registration statement on Form F-1 (No. 333-276877). This prospectus supplement is being filed to update and supplement the information in the Prospectus with information contained in our Current Report on Form 6-K filed with the Securities and Exchange Commission on March 11, 2024 (the “Current Report”). Accordingly, we have attached the Current Report to this prospectus supplement.

This Prospectus and prospectus supplement relate to the resale, from time to time, by the selling shareholders named in the Prospectus (the “Selling Shareholders”) of an aggregate of up to 45,000,000 of our Ordinary Shares, US$0.01 par value per Ordinary Share (the “Ordinary Shares”), reserved for issuance (i) upon the conversion of currently outstanding 4% discount convertible promissory notes (the “Notes”) held by the Selling Shareholders (the “Conversion Shares”) and (ii) upon exercise of currently outstanding warrants (the “Warrants”) held by the Selling Shareholders (the “Warrant Shares”). The Notes and Warrants were issued to the Selling Shareholders on January 9, 2024 (the “Closing Date”).

We registered the resale of up to an aggregate of 45,000,000 Conversion Shares and Warrant Shares as required by the Registration Rights Agreement, dated as of July 11, 2023, as amended (the “Registration Rights Agreement”), by and among us and the Selling Shareholders.

The Conversion Shares include Ordinary Shares issuable upon conversion of $10,000,000.00 in aggregate principal amount of the Notes and in accruing interest which may be paid by the Company in Conversion Shares with the written consent of the Selling Shareholders (including Ordinary Shares reserved for potential issuance in the event of possible future default or dilution adjustments). The Notes are convertible at a conversion price of (i) $4.00 per Ordinary Share (the “Fixed Conversion Price”), or (ii) 92% of the lowest daily variable-weighted average price (the “VWAP”) per Ordinary Share during the 10 trading days preceding the conversion (the “Variable Conversion Price”). The Variable Conversion Price has a floor of $0.55 per Ordinary Share (the “Floor Conversion Price”). The Fixed Conversion Price has a one-time reset on the 6-month anniversary following the Closing Date to the lower of (x) the initial Fixed Conversion Price, (y) the initial Variable Conversion Price, or (z) 130% of the daily VWAP per Ordinary Share on the trading day prior to the reset date. The Notes provide for adjustment of the Fixed Conversion Price for, inter alia, stock dividends, stock splits, stock combinations, rights offerings, pro rata distributions of assets, reclassifications of Ordinary Shares, exchanges of Ordinary Shares or substitutions of Ordinary Shares, dilutive issuances, certain option issuances and issuances of convertible securities. At the Floor Conversion Price, the Notes are convertible into an aggregate of 19,636,364 Ordinary Shares.

The Warrant Shares include Ordinary Shares issuable upon exercise of the Warrants (including Ordinary Shares reserved for potential issuance in the event of possible future default or dilution adjustments). The Warrants are exercisable, immediately upon issuance at the option of the holders, at an exercise price per Ordinary Share equal to initial Fixed Conversion Price for the Notes ($4.00 per Ordinary Share), subject to a one-time reset on the 6-month anniversary of the Closing Date to 120% of the daily VWAP per Ordinary Share on the trading day prior to the reset date. Pursuant to the Purchase Agreement, on the Closing Date, the Selling Shareholders were issued the Initial Warrants to purchase up to an aggregate of 2,288,678 Ordinary Shares.

To the extent that Conversion Shares and/or Warrant Shares are issued by the Company under the terms of the Notes and Warrants, substantial amounts of Ordinary Shares could be issued and resold, which would cause dilution and may impact the Company’s stock price. See “Risk Factors” and “Convertible Note Financing” in the Prospectus for additional information.

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We are not selling any securities under this Prospectus and will not receive any of the proceeds from the sale of our Conversion Shares or Warrant Shares by the Selling Shareholders. However, we may receive proceeds from the exercise of the Warrants, which, if exercised in full for an aggregate of 2,288,678 Ordinary Shares and for cash at the current $4.00 exercise price per Ordinary Share, would result in gross proceeds to us of approximately $9,154,712.00. There is no assurance that the Selling Shareholders will elect to exercise any of the Warrants for cash and, accordingly, no assurance that we will receive any proceeds from the exercise of the Warrants.

We will pay the expenses of registering the Conversion Shares and Warrant Shares offered by this Prospectus, but all selling and other expenses incurred by the Selling Shareholders will be paid by the Selling Shareholders. The Selling Shareholders may sell the Conversion Shares and the Warrant Shares offered by this Prospectus from time to time on terms to be determined at the time of sale through ordinary brokerage transactions or through any other means described in this Prospectus under “Plan of Distribution.” The prices at which the Selling Shareholders may sell the Conversion Shares or the Warrant Shares will be determined by the prevailing market price for our Ordinary Shares or in negotiated transactions.

Our Ordinary Shares are listed on the Nasdaq Capital Market under the ticker symbol “LAES.” The last reported sale price of our Ordinary Shares on the Nasdaq Capital Market on March 8, 2024 was $2.09 per share.

This prospectus supplement should be read in conjunction with, and delivered with, the Prospectus and is qualified by reference to the Prospectus except to the extent that the information in this prospectus supplement supersedes the information contained in the Prospectus. This prospectus supplement is not complete without, and may not be delivered or utilized except in connection with, the Prospectus, including any amendments or supplements to it.

Investing in our Ordinary Shares involves risks. See “Risk Factors” beginning on page 19 of the Prospectus for a discussion of information that should be considered in connection with an investment in our Ordinary Shares.

Neither the U.S. Securities and Exchange Commission (“SEC”) nor any other regulatory body has approved or disapproved of these securities or passed upon the accuracy or adequacy of this Prospectus Supplement No. 3. Any representation to the contrary is a criminal offense.

The date of this Prospectus Supplement is March 11, 2024.

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 6-K/A

(Amendment No. 1)

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16 under the

Securities Exchange Act of 1934

Date of report: For the month of March 2024

Commission File Number: 001-41709

SEALSQ CORP

(Exact Name of Registrant as Specified in Charter)

N/A

(Translation of Registrant’s name into English)

British Virgin Islands

Avenue Louis-Casaï 58

1216 Cointrin, Switzerland

Not Applicable

(State or other jurisdiction of incorporation or organization)

(Address of principal executive office)

(I.R.S. Employer Identification No.)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

☒ Form 20-F

☐ Form 40-F

This Report on Form 6-K/A (this “Amendment”) amends the Report on Form 6-K of SEALSQ Corp (the “Company”) furnished with the Securities and Exchange Commission on March 7, 2024 (the “Original 6-K”). This Amendment is being furnished solely to correct a typographical error in the appointment date of John O’Hara. The reference to John O’Hara’s appointment date to the Company’s Board of Directors of “February 14, 2023” in the Original 6-K, is hereby replaced with “February 14, 2024”.

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SIGNATURES

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, thereunto duly authorized.

Date: March 11, 2024	SEALSQ CORP

	By:	/s/ Carlos Moreira
		Name: Carlos Moreira
		Title: Chief Executive Officer

	By:	/s/ John O’Hara
		Name: John O’Hara
		Title: Chief Financial Officer