Indicate by check mark whether the registrant files or will file annual
reports under cover of Form 20-F or Form 40-F:
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.
Exhibit 99.1

WISeKey Announces Planned
Effectiveness of Redomiciliation from Switzerland to the British Virgin Islands
Zug, Switzerland,
September 25, 2026 – WISeKey International Holding Ltd (“WISeKey” or the “Company”) (SIX: WIHN;
NASDAQ: WKEY) today announced that it expects the previously announced redomiciliation of WISeKey from Switzerland to the British Virgin
Islands to become effective on October 2, 2026 (the “Redomiciliation”). The Redomiciliation is being implemented through the
cross-border merger of WISeKey with and into its wholly owned British Virgin Islands subsidiary, WISeQey Corp. (formerly known as WISeKey
International Corp., “WISeQey”), with WISeQey continuing as the surviving company (the “Merger”). The Merger and
Redomiciliation are expected to become legally effective on October 2, 2026, following completion of the applicable registration procedures.
Upon the effectiveness
of the Merger:
| ● | WISeKey will be absorbed into WISeQey and WISeKey
will cease to exist as a separate legal entity; and |
| ● | WISeQey will succeed to all of the assets, rights,
liabilities and obligations of WISeKey; |
The Redomiciliation is
not expected to change WISeKey’s underlying businesses or operations. The WISeQey’s operational headquarters and place of
effective management will remain in Switzerland, and its global operations will continue as before.
In connection with the
expected completion of the Merger, the ordinary shares of WISeQey are expected to commence trading on the Nasdaq Global Market under the
ticker symbol “WQEY” and on the SIX Swiss Exchange, where they will have a primary listing, under the ticker symbol “WQEY”,
on or about October 5, 2026.
We expect October 2,
2026 to be the last day of trading for the existing American Depositary Shares of WISeKey on Nasdaq and for the existing Class B shares
of WISeKey on SIX Swiss Exchange. Following delisting and cancellation, holders of WISeKey securities will receive the applicable securities
of WISeQey in accordance with the exchange ratios, elections and settlement procedures previously communicated to shareholders and described
in the prospectus relating to the Merger, with the first day of trading for the WISeQey ordinary shares expected to occur on October 5,
2026.
WISeKey shareholders
approved the Merger and the related Merger Agreement at the Extraordinary General Meeting held on September 9, 2026.
Carlos Moreira, Founder,
Chairman and CEO of WISeKey, said: “The completion of our redomiciliation marks an important milestone in the evolution of WISeKey.
It also marks the transition from WISeKey to WISeQey, a new name that symbolizes our strategic expansion into the quantum-security era.
For 27 years, WISeKey has built its expertise around cybersecurity, digital identity, trusted semiconductors and secure communications.
WISeQey represents the extension of that experience into the quantum world, with quantum security becoming an increasingly important pillar
across our technologies and investments. The ‘Q’ in WISeQey reflects this evolution. Our objective is to combine nearly three
decades of cybersecurity expertise with post-quantum cryptography, quantum technologies, secure semiconductors, trusted AI and satellite-based
secure communications to help build the next generation of digital trust infrastructure. With WISeQey’s redomiciliation to the British
Virgin Islands, we believe the new corporate structure will provide greater flexibility to support our continued international development
and access to global capital markets, while maintaining our operational headquarters, effective management and roots in Switzerland.
This is therefore
more than a change of domicile and corporate name. It represents the next chapter of WISeKey: building on the 27-year heritage of WISeKey
while expanding our mission from securing today’s digital world to securing the emerging quantum world. We would like to thank our
shareholders, employees, partners and advisors for their continued support throughout this transformation.”
About WISeKey
WISeKey International Holding Ltd (“WISeKey”,
SIX: WIHN; Nasdaq: WKEY) is a global leader in cybersecurity, digital identity, and IoT solutions platform. It operates as a Swiss-based
holding company through several operational subsidiaries, each dedicated to specific aspects of its technology portfolio. The subsidiaries
include (i) SEALSQ Corp (Nasdaq: LAES), which focuses on semiconductors, PKI, and post-quantum technology products, (ii) WISeID, which
specializes in RoT and PKI solutions for secure authentication and identification in IoT, blockchain, and AI, (iii) WISeSat AG, which
focuses on space technology for secure satellite communication, specifically for IoT applications, (iv) WISe.ART Corp, which focuses on
trusted blockchain NFTs and operates the WISe.ART marketplace for secure NFT transactions, and (v) SEALCOIN AG, which focuses on decentralized
physical internet with DePIN technology and houses the development of the SEALCOIN platform.
Each subsidiary contributes to WISeKey’s mission of securing
the internet while focusing on their respective areas of research and expertise. Their technologies seamlessly integrate into the comprehensive
WISeKey platform. WISeKey secures digital identity ecosystems for individuals and objects using blockchain, AI, and IoT technologies.
With over 1.6 billion microchips deployed across various IoT sectors, WISeKey plays a vital role in securing the Internet of Everything.
Trusted by the OISTE/WISeKey cryptographic Root of Trust, WISeKey provides secure authentication and identification for IoT, blockchain,
and AI applications. The WISeKey Root of Trust ensures the integrity of online transactions between objects and people. For more information
on WISeKey’s strategic direction and its subsidiary companies, please visit www.wisekey.com.
Press and investor contacts:
WISeKey International Holding Ltd
Company Contact: Carlos Moreira
Chairman & CEO
Tel: +41 22 594 30 00
info@wisekey.com |
WISeKey Investor Relations (US)
Contact: Lena Cati
The Equity Group Inc.
Tel: +1 212 836-9611
lena.cati@theequitygroup.com |
Disclaimer:
This communication expressly
or implicitly contains certain forward-looking statements concerning WISeKey International Holding Ltd and its business. Such statements
involve certain known and unknown risks, uncertainties and other factors, which could cause the actual results, financial condition,
performance or achievements of WISeKey International Holding Ltd to be materially different from any future results, performance or achievements
expressed or implied by such forward-looking statements. WISeKey International Holding Ltd is providing this communication as of this
date and does not undertake to update any forward-looking statements contained herein as a result of new information, future events or
otherwise.
This press release does not constitute an offer
to sell, or a solicitation of an offer to buy, any securities, and it does not constitute an offering prospectus within the meaning of
the Swiss Financial Services Act (“FinSA”) or advertising within the meaning of the FinSA. Investors must rely on their own
evaluation of WISeKey and its securities, including the merits and risks involved. Nothing contained herein is, or shall be relied on
as, a promise or representation as to the future performance of WISeKey.
Important Additional Information and Where
to Find It
In connection with the merger, WISeQey filed with
the U.S. Securities and Exchange Commission (the “SEC”) a registration statement on Form F-4 (File No. 333-297507), which
was declared effective on July 31, 2026 and includes a prospectus of WISeQey . INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE REGISTRATION
STATEMENT, THE PROSPECTUS, AND ANY OTHER RELEVANT DOCUMENTS FILED OR TO BE FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY, BECAUSE
THEY CONTAIN IMPORTANT INFORMATION ABOUT THE MERGER. The registration statement, prospectus, and other documents filed by WISeKey or WISeQey
with the SEC may be obtained free of charge at the SEC’s website at www.sec.gov or by directing a request to WISeKey International
Holding Ltd, General-Guisan-Strasse 6, 6300 Zug, Switzerland.
Participants in the Solicitation
WISeKey, WISeQey, and their respective directors
and executive officers may be deemed to have been participants in the solicitation of proxies from WISeKey’s shareholders in connection
with the merger. Information regarding the interests of these directors and executive officers in the merger is included in the prospectus.
Additional information regarding WISeKey’s directors and executive officers is also included in WISeKey’s Annual Report on
Form 20-F for the fiscal year ended December 31, 2025, filed with the SEC. These documents are available free of charge at the SEC’s
website at www.sec.gov.
No Offer or Solicitation
This communication is for informational purposes
only and is not intended to and shall not constitute an offer to sell or the solicitation of an offer to buy any securities, nor shall
there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration
or qualification under the securities laws of any such jurisdiction. No offering of securities shall be made except by means of a prospectus
meeting the requirements of Section 10 of the U.S. Securities Act of 1933, as amended.
Cautionary Statement Regarding Forward-Looking
Statements
This communication contains “forward-looking
statements” within the meaning of Section 27A of the U.S. Securities Act of 1933, as amended, and Section 21E of the U.S. Securities
Exchange Act of 1934, as amended. Forward-looking statements are typically identified by words such as “expect,” “anticipate,”
“intend,” “plan,” “believe,” “seek,” “estimate,” “will,” “should,”
“would,” “could,” “may,” and similar expressions. These forward-looking statements include, but are
not limited to, statements regarding: the anticipated benefits of the redomiciliation and merger; the expected timing and completion of
the merger and the effectiveness thereof; the satisfaction of remaining conditions to the merger, including regulatory approvals; and
the expected listing of WISeQey shares on Nasdaq and SIX Swiss Exchange.
These forward-looking statements are based on
current expectations, estimates, forecasts, and projections about the industry and markets in which WISeKey and WISeQey operate, and management’s
beliefs and assumptions. These statements are not guarantees of future performance and involve risks, uncertainties, and assumptions that
are difficult to predict. Important factors that could cause actual results to differ materially from forward-looking statements include,
but are not limited to: the risk that the merger may not be completed in a timely manner or at all; failure to satisfy remaining closing
conditions; failure to obtain required regulatory approvals, including from Nasdaq, SIX Swiss Exchange, or the Swiss Takeover Board; the
risk that the anticipated benefits of the redomiciliation may not be realized; changes in applicable laws or regulations; general economic
and market conditions; and other risks and uncertainties described in WISeKey’s filings with the SEC, including its Annual Report
on Form 20-F. Investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date
of this communication. WISeKey does not undertake any obligation to update or revise any forward-looking statements, whether as a result
of new information, future events, or otherwise, except as required by law.