OpenAI Acquires AI Security Platform Promptfoo to Harden Enterprise Agent Testing
The deal brings automated red-teaming and vulnerability detection into OpenAI's Frontier enterprise platform, used by more than a quarter of Fortune 500 companies.
OpenAI announced on Monday that it has agreed to acquire Promptfoo, an AI security and evaluation startup co-founded in 2024 by Ian Webster and Michael D'Angelo. Promptfoo's platform is designed to help enterprises identify and remediate vulnerabilities in AI systems during development, covering risks such as prompt injection, data leakage, jailbreak attempts, tool misuse, and out-of-policy agent behaviors.
The acquisition terms were not disclosed.
The startup had quietly built wide enterprise adoption before the deal, with its open-source CLI and evaluation tools trusted by more than 25 percent of Fortune 500 companies. The acquisition is intended to accelerate the integration of automated security testing and governance capabilities directly into OpenAI Frontier, the company's platform for building and operating AI coworkers that launched in early February 2026.
OpenAI said Promptfoo's technology will be embedded into Frontier's development workflows, allowing enterprises to identify agent risks earlier and document testing, monitor changes over time, and meet governance, risk, and compliance expectations. The combination is particularly timely as enterprises deploy agents with access to sensitive data, business tools, and real-world systems — environments where the consequences of security failures are significantly higher than in standard chatbot deployments.
Srinivas Narayanan, CTO of B2B Applications at OpenAI, called Promptfoo's work critical for businesses deploying secure and reliable AI applications at enterprise scale. Ian Webster, Promptfoo's CEO, said the acquisition would accelerate the company's mission, noting that as AI agents become more connected to real data and systems, securing and validating them becomes both more challenging and more consequential.
Promptfoo's core open-source project will remain publicly available and continue to be developed.
The deal reflects OpenAI's growing emphasis on enterprise infrastructure as it competes with Anthropic and Google for large business contracts. With agentic AI deployments expanding rapidly, security and auditability of AI behavior in production environments has emerged as a top concern for corporate customers.
Read the original reporting at OpenAI.
