EQT Growth led a funding round exceeding $500m in US-based cybersecurity specialist ReliaQuest, marking a major bet on AI-powered security operations.

The deal values the company at $3.4bn and was joined by existing investors KKR, FTV Capital, Ten Eleven Ventures, and Finback Investment Partners.

The investment will accelerate ReliaQuest’s global expansion and support its continued innovation in agentic AI automation for cybersecurity.

ReliaQuest’s proprietary platform, GreyMatter, integrates with more than 200 security tools to help enterprise teams detect and respond to threats in minutes. By automating manual tasks and enhancing visibility across complex environments, GreyMatter delivers measurable outcomes while increasing the value of existing infrastructure.

The deal comes amid rapid growth for ReliaQuest. Since its last funding round in 2020, the company has grown its Annual Recurring Revenue more than fourfold, now exceeding $300m. The firm is expanding at over 30% annually and remains profitable.

EQT Growth Partner Kirk Lepke said: “ReliaQuest has accelerated ahead of the pack by enriching GreyMatter with AI and automation capabilities. It is now one of the few software providers able to manage security operations in the most complex enterprise environments.”

EQT’s investment underscores its commitment to backing technology leaders solving mission-critical challenges at scale. The firm was advised by Piper Sandler and Freshfields US LLP.