Harvey has added foundation models from Anthropic and Google its AI platform, moving beyond a single-model setup powered by long-time partner and investor OpenAI.
The change means legal tasks will now be routed to the model that performs best, with firms like A&O Shearman already using Harvey to build AI-powered legal tools.
Harvey, the legal AI platform used by top UK firms including A&O Shearman and Macfarlanes, has officially gone multi-model, adding models from Anthropic and Google to its platform alongside long-time partner OpenAI.
The company says the move will allow it to route legal tasks to the best-performing model depending on the use case, with users also able to select models manually when needed.
"There’s no longer a single ‘best’ model", Harvey wrote in a blog post, "but an array of premier models, each particularly suited to different legal tasks and preferences."
The shift is a big move for a company that’s not only built on OpenAI tech, but also counts OpenAI as one of its first investors. Now, Harvey says it wants to give customers "more optionality", while still keeping its existing partnerships close.
Why it matters
Harvey has scaled rapidly since it launched in 2022 with ex-Big Law lawyer Winston Weinberg and DeepMind research scientist Gabe Pereyra at the helm.
It’s raised more than $400 million to date, including a $300 million Series D round in February led by existing investor Sequoia - one of the world’s leading VC firms - which doubled its valuation to $3 billion.
But its own internal benchmark - BigLaw Bench - showed a more nuanced picture of model performance across legal tasks, with Harvey saying "There is still a substantial gap in which model is best suited to a particular legal task".
One example given by the company is that Gemini 2.5 Pro excels at legal drafting, but is less reliable for trial preparation and oral arguments "due to difficulties in reasoning effectively about complex evidentiary rules like hearsay which models from other providers understand more clearly."
What it means for firms
Harvey’s biggest law firm clients - including A&O Shearman, which is rolling out Harvey-built legal agents to sell to its own clients - will now benefit from model routing based on task type, which should improve output quality across drafting, analysis and multi-step workflows.
Firms will also gain access to a model selector and new transparency tools, including a public leaderboard for BigLaw Bench showing how different models perform across Harvey’s legal benchmarks, and commentary from top lawyers assessing output quality beyond numerical scores.
What they said
"We are incredibly fortunate to have OpenAI as an investor and key collaborator", said CEO Weinberg in a statement to TechCrunch.
"And, we are energised to add to our options for customers as we continue to serve the needs of our customers globally."
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