WISeKey, The Hashgraph Group and Hedera Launch QAIT Q-Day Security Assessment Platform on the SEALCOIN Quantum Marketplace First Quantum Security Service to Launch Within SEALCOIN’s Dedicated Quantum Marketplace, Enabling Organizations to Assess and Prepare for Quantum-Era Cybersecurity Risks Geneva, Switzerland – June 8, 2026 — WISeKey International Holding Ltd (SIX: WIHN; NASDAQ: WKEY), a global leader in cybersecurity, digital identity and IoT, today announced the launch of a dedicated Quantum Marketplace within the SEALCOIN platform and the introduction of its flagship application, the QAIT Q-Day Security Assessment Platform. Developed in collaboration with The Hashgraph Group (THG) and Hedera, the platform is designed to help enterprises, governments and critical infrastructure operators evaluate, monitor and mitigate cybersecurity risks associated with the emergence of quantum computing. As quantum computers advance toward the capability of breaking traditional public-key cryptography systems such as RSA and ECC, cybersecurity experts worldwide are warning of the approaching “Q-Day”, the moment when existing digital security infrastructures could become vulnerable to quantum attacks. The consequences could affect financial systems, critical infrastructure, government communications, healthcare networks, digital identities, IoT ecosystems and blockchain technologies. The QAIT Q-Day Security Assessment Platform combines artificial intelligence, blockchain transparency and post-quantum security expertise to provide organizations with a comprehensive evaluation of their readiness for the quantum era. The platform represents a dedicated service offering within the SEALCOIN Quantum Marketplace, a specilized environment for quantum-era cybersecurity, post-quantum cryptography, quantum risk assessment, secure digital identity and future quantum-enabled services. Through the marketplace, enterprises, governments, researchers and technology providers will be able to access specialized quantum readiness services, security assessments, compliance reporting tools, post-quantum migration capabilities and future quantum-secure applications using QAIT as the native utility and settlement token. Built on Hedera’s enterprise-grade and quantum-secure distributed ledger technology and supported by The Hashgraph Group’s technology engineering team and the