UNITED STATES

SECURITIES AND EXCHANGECOMMISSION

WASHINGTON, DC 20549

FORM 6-K

Report of Foreign PrivateIssuer

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

Securities Exchange Act of 1934

For the month of July 2025

Commission File Number: 001-41709

 SEALSQCORP

(Exact Name ofRegistrant as Specified in Charter)

N/A

(Translationof Registrant’s name into English)

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

☒ Form20-F         ☐ Form 40-F

SIGNATURES

Pursuant to the requirements ofthe Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereuntoduly authorized.

SEALSQCorp Announces H1 2025 Preliminary Revenue and Other Key Financial Metrics: Updates on Planned Deployment of Post-Quantum Security Solutionsby 2025 Year-End

Announces FY 2025 revenue guidanceof between $16.0 million to $20.0 million, representing year-on-year growth of 45% - 82%

New Quantum Resistant Chip Offering,Quantix Edge Partnership and IC’ALPS ASIC Acquisition to Drive 2026 Revenue Surge and Global Expansion

 
Geneva, Switzerland, July 3, 2025 -- SEALSQ Corp (NASDAQ: LAES) ("SEALSQ" or "Company"), a company that focuses ondeveloping and selling Semiconductors, PKI, and Post-Quantum technology hardware and software products, today reports its preliminaryunaudited financial metrics for the six-month period ended June 30, 2025 (H1 2025). The Company also updates on its transformative operationalmilestones, announces initial FY 2025 revenue guidance and reaffirms outlook for 2026 and beyond.

H12025 Key Financial Metrics

AnnouncesInitial Full Year 2025 Revenue Guidance and Growth Catalysts

CarlosMoreira, CEO of SEALSQ, commented: “While H1 2025 marked the expected continuation of a transitional period as we aligned our portfoliowith the post-quantum era, H2 2025 will be a pivotal inflection point for SEALSQ. With clear visibility into our current business andgrowth drivers, we expect our second half of the year to be substantially stronger than the first half in terms of revenue. Thus, forthe second half of 2025, we expect revenues of between $11 million and $15 million, fueled by major commercial projects and the consolidationof some revenues relating to IC’ALPS.”

Mr. Moreiraadded, “With standard QVault TPM and custom ASICs solutions, and our expanding network of Test and Personalization Centers, we arelaying the foundation for important growth in 2026. Although we do not expect our Spain-based Personalization Center project to be fullyactivated so as to have a significant impact on our 2025 revenue, we believe it will act as a catalyst for 2026, and we expect it to generatesignificant revenues that year. These factors, combined with our global PQC leadership, position SEALSQ for accelerated growth in 2026.We stand at a pivotal moment in the evolution of digital trust — where semiconductor security-based solutions and quantum-resistanttechnologies are becoming the backbone of a digital world that is secure, connected, and built for a better future.”

Strategic Milestones Achievedin H1 2025

StrategicInvestments Fueling Growth

Recentcapital infusions have strengthened SEALSQ’s financial position, and enabled the accelerated development of its post-quantum chipportfolio, strategic investments like the acquisition of IC’ALPS SAS for a fixed purchase price of EUR 12.5 million and the$10 million investment in WISeSat.Space for quantum-resilient satellite communication, and the progression of its global Design &Personalization Centers through the recently announced Quantix Edge Security project.

Combinedwith a robust cash reserve of $120 million as of June 30, 2025, these funds well-position SEALSQ to capitalize on opportunities arisingfrom the growing demand for quantum-resistant technologies and drive commercialization in H2 2025 and beyond.

MarketValuation and Strategic Potential

Quantumand post-quantum technology companies often command high valuations despite low current revenues because their value lies in future strategicpotential. Like the internet and mobile revolutions, quantum computing and cryptography are seen as platform shifts that will transformindustries such as cybersecurity, defense, healthcare, and finance. Governments are prioritizing quantum-secure infrastructure for nationalsecurity and digital sovereignty, making post-quantum firms attractive strategic assets regardless of current income. These companiestypically face long R&D cycles, but their intellectual property, research partnerships, and leadership in emerging standards (e.g.,NIST’s Kyber and Dilithium) are seen as major future revenue drivers. The market is expected to follow a winner-takes-most dynamic,with early leaders securing dominant positions. As large enterprises begin migrating to post-quantum cryptography (PQC), a “goldrush” effect is underway, with buyers seeking early access to scalable, quantum-ready solutions.

SEALSQ Post-Quantum Chips:Pioneering Quantum-Resilient Security

SEALSQ’s post-quantum chip portfolio, including the QVault™ Trusted Platform Module (TPM) and QS7001™ hardware platform,leads the industry in delivering hardware-based solutions to counter quantum computing threats. Designed for critical sectors like defense,IoT, satellites, and automotive, these chips ensure long-term data protection against “harvest now, decrypt later” risks.

“Ourpost-quantum chips are meant to be the backbone of tomorrow’s secure, connected ecosystems,” said Jean-Pierre Enguent, CTOof SEALSQ. “With QVault TPM and QS7001, we are empowering industries to stay ahead of quantum vulnerabilities.”

KeyFeatures and Benefits:

Positioned for a Quantum-ResilientFuture

As quantumcomputing advances, SEALSQ is at the forefront of countering “harvest now, decrypt later” threats. The Company’s earlyadoption of NIST-approved algorithms, leadership in RISC-V secure microcontrollers, and strategic partnerships in drone security, automotivesystems, and sovereign identity infrastructure solidify its role as a critical enabler of cybersecurity. SEALSQ’s roadmap alignswith emerging mandates, including the EU Cyber Resilience Act and the U.S. Cyber Trust Mark, positioning it as a trusted partner for governmentsand enterprises worldwide.

For furtherdetails on SEALSQ’s financial performance and strategic initiatives, visit www.sealsq.com.

AboutSEALSQ:

SEALSQ is a leading innovator in Post-QuantumTechnology hardware and software solutions. Our technology seamlessly integrates Semiconductors, PKI (Public Key Infrastructure), andProvisioning Services, with a strategic emphasis on developing state-of-the-art Quantum Resistant Cryptography and Semiconductors designedto address the urgent security challenges posed by quantum computing. As quantum computers advance, traditional cryptographic methodslike RSA and Elliptic Curve Cryptography (ECC) are increasingly vulnerable.

SEALSQ is pioneering the development of Post-QuantumSemiconductors that provide robust, future-proof protection for sensitive data across a wide range of applications, including Multi-FactorAuthentication tokens, Smart Energy, Medical and Healthcare Systems, Defense, IT Network Infrastructure, Automotive, and Industrial Automationand Control Systems. By embedding Post-Quantum Cryptography into our semiconductor solutions, SEALSQ ensures that organizations stay protectedagainst quantum threats. Our products are engineered to safeguard critical systems, enhancing resilience and security across diverse industries.

For more information on our Post-Quantum Semiconductorsand security solutions, please visit www.sealsq.com.

Forward-LookingStatements

Thiscommunication expressly or implicitly contains certain forward-looking statements concerning SEALSQ Corp and its businesses. Forward-lookingstatements include statements regarding our business strategy, financial performance, results of operations, market data, events or developmentsthat we expect or anticipate will occur in the future, as well as any other statements which are not historical facts. Although we believethat the expectations reflected in such forward-looking statements are reasonable, no assurance can be given that such expectations willprove to have been correct. These statements involve known and unknown risks and are based upon a number of assumptions and estimateswhich are inherently subject to significant uncertainties and contingencies, many of which are beyond our control. Actual results maydiffer materially from those expressed or implied by such forward-looking statements. Important factors that, in our view, could causeactual results to differ materially from those discussed in the forward-looking statements include SEALSQ's ability to continue beneficialtransactions with material parties, including a limited number of significant customers; market demand and semiconductor industry conditions;and the risks discussed in SEALSQ's filings with the SEC. Risks and uncertainties are further described in reports filed by SEALSQ withthe SEC.

SEALSQCorp is providing this communication as of this date and does not undertake to update any forward-looking statements contained hereinas a result of new information, future events or otherwise.