WISeKey Renews WebTrust Compliance for OISTE/WISeKey Global Root of Trust

WISeKey Renews WebTrust Compliance for OISTE/WISeKey Global Root of Trust

Geneva and Zug, Switzerland – July 29, 2025 – WISeKey International Holding Ltd (("WISeKey", SIX: WIHN, NASDAQ:WKEY), a global leader in cybersecurity and IoT, today announced the successful renewal of its WebTrust Seal of Assurance. This renewal confirms that WISeKey's OISTE/WISeKey Trust Model and Certification Authority (CA) services meet the rigorous audit criteria established by the WebTrust program.

The WebTrust for Certification Authorities program, now overseen by CPA Canada, is designed to strengthen public trust in digital certificate services and the broader PKI ecosystem. By maintaining this prestigious certification, WISeKey reinforces its position as a trusted provider of secure digital identity and cybersecurity solutions.

Comprehensive Audit Scope

WISeKey has successfully passed WebTrust audits in the following critical domains:

• WebTrust for Certification Authorities – validates WISeKey's operational integrity in the issuance and lifecycle management of digital certificates.
• WebTrust for Baseline Requirements – confirms compliance with the CA/B Forum's security and issuance standards for publicly trusted certificates.
• WebTrust for Extended Validation (EV) – verifies WISeKey's adherence to strict requirements for issuing EV SSL certificates.
• WebTrust for S/MIME – introduced in 2024, it confirms WISeKey's secure practices in issuing digital certificates for encrypted email communications.
• WebTrust for Network Security – newly added in 2025, itattests to WISeKey's robust cybersecurity controls across its infrastructure.
  
  
  
  

Advancing Trust Services

WISeKey delivers its trust services via next-generation certificate management platforms, which offer automated provisioning (via ACME and APIs), crypto-agility, and streamlined renewal and revocation processes, reducing operational risks and improving efficiency.

This latest certification also covers WISeKey's newly deployed Root Certification Authorities, which serve as the foundation for its post-quantum trust services. Through its subsidiary, SEALSQ Corp (NASDAQ:LAES), WISeKey is investing heavily in quantum-resistant solutions that integrate both software and hardware components.

Carlos Moreira, Founder and CEO of WISeKey, stated: "The renewal of our WebTrust assurance demonstrates the reliability and resilience of WISeKey's Trust Services. It reflects our commitment to maintaining the highest standards of security and compliance for our global clients."

Expanding Global Recognition

In addition to WebTrust accreditation, WISeKey undergoes regular assessments to meet the diverse compliance requirements of its multinational clientele. These include accreditations for:

• Matter, the smart home standard supported by CSA, Google, Apple, and Amazon.
• Wi-SUN Alliance, reflects WISeKey's standing as a trusted root for critical IoT and home automation.
• GSMA, ensurs compliance with mobile security standards, such as the issuance of digital certificates for eSIM.
  
  
  
  

The Role of OISTE Roots in PKI and WISeKey Trust Services delivered by the WISeKey Holding

OISTE Root Certificate Authorities (Root CAs) sit at the top of the PKI hierarchy. They issue and validate subordinate CAs, anchoring trust for all digital certificates downstream. If a Root CA is compromised, the entire trust chain can be invalidated, making trustworthiness and security paramount.

Certificates issued by trusted CAs enable authentication, encryption, and integrity for digital communications. EV certificates, in particular, offer enhanced validation and are preferred for high-assurance applications.

By maintaining WebTrust accreditation, OISTE's Root CAs remain embedded in major browsers and operating systems, ensuring seamless interoperability and global recognition.

WISeKey SA, another WISeKey subsidiary which specializes in RoT and PKI solutions for secure authentication and identification in IoT, Blockchain, and AI, acts as a "Trust Center" for the rest of companies of the group, centralizing and optimizing the investment in datacenter and PKI technologies.

For more information, visit: www.oiste.org and www.wisekey.com

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) WISeKey SA 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 house 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. The company's semiconductors generate valuable Big Data that, when analyzed with AI, enable predictive equipment failure prevention. 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.

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"), the FinSa's predecessor legislation 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.



Press and Investor Contacts

WISeKey International Holding Ltd Company Contact: Carlos Moreira Chairman & CEO Tel: +41 22 594 3000 [email protected]

WISeKey Investor Relations (US)  The Equity Group Inc. Lena Cati Tel: +1 212 836-9611 [email protected]