SAN FRANCISCO — Patronus AI announced a $50 million Series B funding round on June 25, 2026. Greenfield Partners led the round, with participation from Notable Capital, Lightspeed, Datadog, and Samsung. The funding brings Patronus AI's total capital raised to $70 million.

Founded in 2023 by former Meta AI researchers Anand Kannappan and Rebecca Qian, the San Francisco-based company builds simulated digital environments to assess AI agent performance. Patronus AI uses what it terms "digital world models" to create replicas of websites and internal systems. In these environments, agents are stress-tested after initial training that uses reinforcement learning, a process that iteratively rewards successful task completion and penalizes errors. The company currently provides simulated digital worlds for finance and software engineering and evaluates agent behavior without human intervention.

Patronus AI's revenue has grown 15-fold over the past year. Anand Kannappan, co-founder of Patronus AI, discussed the challenges in evaluating AI. "Today we're very focused on the problems that are verifiable, so the problems that you can immediately check and verify, but there are a ton more areas that are very non-verifiable or very hard to verify," Kannappan said. "We want to be able to actually create the environment in which you can operate an agent that can run for 10 hours or 10 days or 10 weeks."

Glenn Solomon, a managing director at Notable Capital, commented on the company's capabilities. "Patronus is really good at spotting the hacks and making sure they are holding the models accountable," Solomon said.