Harvey raises $550M Series F at $15.5B valuation; acquires Guardrails AI
- Scale
- $550M Series F co-led by Diffusion and Lightspeed. Total raised >$1.5B. ARR >$400M. Simultaneously acquired Guardrails AI (agent security), fourth acquisition of 2026.
- Vendors
- Harvey AI
- Significance
- High
- Confidence
- Confirmed
Why this matters
This firm is putting capital behind AI, with Harvey AI in the stack. This is a high-significance signal for buyers benchmarking their panel.
Harvey closed a $550M Series F co-led by Diffusion and Lightspeed at a $15.5B valuation, up 41% from $11B in March. ARR reportedly exceeds $400M. Simultaneously acquired Guardrails AI, an agent security startup, marking Harvey's fourth acquisition of 2026. Also launched Harvey Tenet, its first post-trained open-weight model built on Moonshot's Kimi K3.
- Scale / Terms
- $550M Series F co-led by Diffusion and Lightspeed. Total raised >$1.5B. ARR >$400M. Simultaneously acquired Guardrails AI (agent security), fourth acquisition of 2026.
- Significance
- High
- Source type
- Trade Press
Vendors involved
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