EnduroSat and WISeSat.Space Partner to Deliver Quantum-Resilient Secure IoT Nanosatellite Infrastructure

FOR IMMEDIATE RELEASE

EnduroSat and WISeSat.Space Partner to Deliver Quantum-Resilient Secure IoT Nanosatellite Infrastructure

Sofia, Bulgaria & Geneva, Switzerland – July 28, 2025 – WISeKey International Holding AG ((SIX: WIHN, NASDAQ:WKEY), a leading global cybersecurity, blockchain, and IoT company, via its subsidiary WISeSat.Space AG, a company that focuses on space technology for secure satellite communication, specifically for IoT applications, and EnduroSat, a leading provider of software-flexible satellites, as part of their strategy to diversify partners in the industry, are pleased to announce the signing of a Memorandum of Understanding (MoU) to establish a framework aimed at achieving a strategic partnership to extend the development and deployment of ultra-secure, quantum-resilient nanosatellite systems for Internet of Things (IoT) applications.

The cooperation targets the integration of SEALSQ secure elements, such as the VaultIC292, VaultIC408, and QS7001, into satellite payloads and ground-level endpoints. These components enable strong hardware-based security and digital identity protection, ensuring encrypted communications and trusted authentication across the IoT satellite network.

The project aims to implement post-quantum cryptographic (PQC) algorithms, aligned with NIST recommendations such as CRYSTALS-Kyber and CRYSTALS-Dilithium, to safeguard against future quantum computing threats. WISeSat will provide the PQC algorithmic stack and support, while EnduroSat will incorporate these into its satellite and communication platform.

EnduroSat brings its expertise in modular satellite design, in-orbit validation, and scalable deployment systems. It will lead the physical integration of SEALSQ secure components into next-generation satellite buses and contribute to the overall mission architecture. WISeSat will support cryptographic integration and field engineering resources, ensuring that each system meets high-security and resilience benchmarks.

The partnership further outlines the future integration of post-quantum cryptographic solutions and secure elements into both EnduroSat and WISeSat satellite infrastructures. EnduroSat will also support the design and deployment of WISeSat's future missions, ensuring compliance with defined security and performance requirements.

This collaboration builds on WISeSat's successful deployment of its new-generation PQC-ready nanosatellite in December 2025 and EnduroSat's proven record of delivering more than 60+ satellites to orbit for institutional, scientific, and commercial customers. The resulting architecture will offer scalable, tamper-proof IoT connectivity services from Low Earth Orbit (LEO), critical for use-cases in logistics, critical infrastructure, defense, and environmental monitoring.

"This partnership with EnduroSat marks a significant step forward in our mission to deliver quantum-resilient, end-to-end secure satellite infrastructure," said Carlos Moreira, Founder and CEO of WISeKey. "By integrating SEALSQ's advanced secure elements into the expanding WISeSat constellation, we are building a tamper-proof communications backbone in space. Together with EnduroSat's modular satellite technology, we are enabling scalable and ultra-secure IoT connectivity services from Low Earth Orbit—critical for securing data and infrastructure in the quantum era."

"We are excited to initiate this partnership," said Raycho Raychev, founder & CEO of EnduroSat. "We hope to accelerate the introduction and establishment of much stronger encryption capabilities into the satellite industry."

About WISeSat.Space

WISeSat.Space AG is pioneering a transformative approach to IoT connectivity and climate change monitoring through its innovative satellite constellation. By providing cost-effective, secure, and global IoT connectivity, WISeSat is enabling a wide range of applications that support environmental monitoring, disaster management, and sustainable practices. The integration of satellite data with advanced climate models holds great promise for enhancing our understanding of climate change and developing effective strategies to combat its impacts. As the world continues to grapple with the challenges of climate change, initiatives like WISeSat's IoT satellite constellation are essential for creating a more resilient and sustainable future.

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.

About EnduroSat

EnduroSat is a space infrastructure builder that engineers, builds, and operates exceptional satellites. The company streamlines space missions in LEO and beyond, handling every step from mission design to launch and operations. EnduroSat serves more than 360 customers globally and employs more than 230 space professionals across 6 locations worldwide. For more information, visit https://www.endurosat.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]

ENDUROSAT EAD Company Contact: Raycho Raychev Founder & CEO [email protected]