Multifactor, the post-quantum security platform making online account access safer for humans and AI agents, has raised $15 million in seed funding. Nexus Venture Partners led the round, with participation from Y Combinator, Taurus Ventures, Honeystone Ventures, Flex Capital, Pioneer Fund, Ritual Capital, and Liquid2 Ventures.
Several prominent operators from security, AI, and enterprise software also joined as investors. These include Mohan and Padma Warrior, Gokul Rajaram, and Mathilde Collin.
The funding follows strong early demand for Multifactor's technology. The platform allows users to share online account access without exposing underlying credentials. Think of it like Google Docs sharing. Instead of handing over a password, you create a shareable link with specific permissions.
Banking platforms, email accounts, calendars, social media profiles, and enterprise systems can all become secure, one-click access links. Users can set permissions to read-only, restrict access by feature, or even limit transactions by dollar amount. Every action gets recorded with cryptographic signatures, protected by post-quantum security technology that the company describes as mathematically unbreakable.
Ph.D. computer scientist and former CIA officer Vivek Nair founded Multifactor alongside Ph.D. mathematician and cryptographer Colin Roberts. The company was built specifically to address security risks created by the rapid rise of agentic AI.
For AI agents, Multifactor provides a secure execution environment that prevents prompt injection, password theft, confused-deputy attacks, and cross-agent hijacking. Access works on a capability basis. Agents can only see or modify what users have specifically granted in advance.
"Passwords were never built for the agentic era, and they're becoming the most fragile link in modern security," said Vivek Nair, CEO and co-founder of Multifactor. "People aren't going to hand AI agents the keys to their calendars, finances, or business systems unless they have complete confidence nothing will go wrong. Multifactor is the easiest, safest, and most verifiable way to collaborate with both humans and AI with security guarantees that are mathematically unbreakable."
Multifactor launched publicly just three weeks ago. The platform draws on a decade of cybersecurity research and the founders' experience deploying offensive and defensive tools inside high-risk national security environments. With identity as the root cause of most application security breaches, the company aims to move users away from password-based systems entirely.
The new funding will accelerate growth and product development as the company scales its zero-trust solution. Multifactor's account manager is currently free to use.
"Multifactor is solving a multi-billion-dollar problem," said Abhishek Sharma, managing director at Nexus Venture Partners. "Adoption of any new technology starts with trust. That, ultimately, is what Multifactor is bringing to the table. They're creating trust. And by doing that, they're eliminating one of the most significant barriers to mainstream adoption of agentic AI."
The investor group reflects strong conviction across the security and AI sectors. Beyond the institutional investors, the round attracted operators with deep experience building and scaling enterprise software companies. Multifactor is part of Y Combinator's F25 batch.
