NIST Endorses SandboxAQ’s HQC as a Post-Quantum Encryption Standard, Cementing Its Role in the Quantum Cybersecurity Vanguard

In a decisive move that will help shape the future of global cybersecurity, the National Institute of Standards and Technology (NIST) has officially named HQC (Hamming Quasi-Cyclic), an encryption algorithm co-developed by SandboxAQ, as one of just five cornerstone algorithms in its post-quantum cryptography (PQC) standardization initiative.

With quantum computing creeping closer to breaking classical encryption systems, NIST’s PQC standards are widely viewed as the digital bulwark for the post-quantum era. HQC, now one of only two algorithms chosen to secure data confidentiality, will be a critical component for protecting everything from cellular communications and payment networks to government systems and enterprise infrastructure.

This marks the second time SandboxAQ’s cryptographic innovations have been selected by NIST. The company previously contributed to SPHINCS+, a signature algorithm included in NIST’s initial 2022 PQC standards. The dual inclusion puts SandboxAQ in an elite category of cryptographic pioneers steering the global response to the looming quantum threat.

“HQC has foundations in coding theory that offer strong theoretical and practical protection against known quantum decryption methods, while its efficient performance profile makes it well-suited to real-world adoption,” said Taher Elgamal, a partner at Evolution Equity Partners and senior advisor at SandboxAQ. Elgamal, often dubbed "the father of SSL," emphasized that this recognition isn’t just a company win—it’s “a win for global security in the face of future quantum disruption.”

From Theory to Global Standard

The HQC protocol is based on error-correcting codes—decades-old mathematical constructs long used to detect and fix errors in data transmission. What makes HQC special is that it applies those principles in a way that thwarts even the most advanced attacks quantum computers are expected to unleash.

Unlike RSA or elliptic-curve cryptography (ECC), both of which are vulnerable to Shor’s algorithm—a quantum method that can rapidly factor large numbers and break current encryption—HQC remains resilient. It also balances computational efficiency and key size, key factors for adoption across large, resource-constrained systems like embedded devices, mobile networks, and cloud platforms.

“We began developing HQC in the 2000s, and by the 2010s, we had demonstrated that this protocol resolved a 40-year-old open problem in code-based key exchanges,” said Carlos Aguilar Melchor, chief cybersecurity scientist at SandboxAQ. “Today, HQC stands as one of only two protocols securing the confidentiality of nearly all global communications.”

Rising as a Post-Quantum Powerhouse

Founded as an AI and quantum spinoff from Alphabet in 2022, SandboxAQ has quickly become one of the most influential players in the quantum security arena. Its impact extends well beyond academic breakthroughs. The company’s AQtive Guard platform—a sophisticated cryptography management system—has been adopted by government agencies and Fortune 500 enterprises alike. The system maps cryptographic assets across sprawling infrastructures, flags vulnerabilities, and ensures compliance with emerging standards like those now set by NIST.

The platform is powered by AI trained on billions of cryptographic findings and features integrations with third-party systems, offering what SandboxAQ describes as “360-degree coverage” across its customers’ environments.

By contributing to nearly half of the PQC standards chosen by NIST, SandboxAQ is more than a participant in the post-quantum race—it’s a driver of the next security paradigm.

As governments and enterprises begin the massive migration to post-quantum cryptography, the inclusion of HQC in NIST’s standards signals a turning point: quantum resilience is no longer a futuristic concept—it’s becoming the new baseline.