Harvey, the San Francisco-based legal AI startup, closed a $550 million funding round on September 9, pushing its valuation to $15.6 billion. That figure is up from $11 billion just six months ago, making Harvey comfortably the most valuable company in the legal AI space.
The round was co-led by Lightspeed Venture Partners and Diffusion, a newly formed firm co-founded by Kris Fredrickson, who has been a prominent investor in Harvey across multiple rounds. New backers Sapphire Ventures and Whale Rock Capital Management joined alongside returning heavyweights Sequoia, Andreessen Horowitz, and Kleiner Perkins. Harvey has now raised more than $1.5 billion in total funding.
Growth that speaks for itself
Harvey’s annual recurring revenue has surpassed $400 million, roughly doubling since March 2026. For context, when the company raised $200 million at an $11 billion valuation in March, it was already considered one of the fastest-growing enterprise AI companies on the planet.
Harvey now serves over 3,000 organizational customers. Around 80% of the Am Law 100, the ranking of the largest US law firms by revenue, use the platform. Several Fortune 10 companies, including Microsoft, are also on the client roster.
An acquisition alongside the raise
Harvey announced the funding alongside its acquisition of Guardrails AI, a San Francisco-based startup focused on AI agent security. The deal brings Guardrails’ co-founders and engineering team into Harvey’s product and development operations.
On the product side, Harvey has recently launched two notable tools. Harvey Tenet is described as the first post-trained open-weight model for legal applications. Harvey LAB, short for Legal Agent Benchmark, provides a framework for evaluating legal AI performance.
From $3 billion to $15.6 billion in under two years
Harvey was founded by Winston Weinberg and Gabe Pereyra, both of whom came from legal professional backgrounds before pivoting into AI. In February 2025, Harvey was valued at $3 billion. Eighteen months and several funding rounds later, that number has more than quintupled.
The growth has been fueled by a deliberate expansion beyond law firms into professional services and corporate legal departments. That broader addressable market helps justify the valuation multiple, even if $15.6 billion for a company with $400 million in ARR (roughly 39x revenue) still raises eyebrows in some circles.