Spellbook, a company formerly known as Rally Legal, and whose product uses GPT-4 and other generative AI models to speed contract drafting and review directly within Microsoft Word, has raised $10.9 million to drive hiring, development and expansion.

The funding was led by Moxxie Ventures, with participation from Thomson Reuters VenturesInovia CapitalThe LegalTech FundBling Capital and others.

Along with the financing news, the company announced its rebranding from Rally Legal to Spellbook. Spellbook was already the name of the AI contract drafting product the company launched last September. Rally’s other products, including a law firm management suite, will remain active and be combined with Spellbook’s AI.

Spellbook says that its product was the first generative AI copilot for lawyers to launch commercially. It leverages GPT-4 and other fine-tuned large language models (LLMs) to enable legal practitioners to draft and review contracts up to four times faster. The product works directly within Microsoft Word.

“Spellbook is focused on empowering lawyers with AI tools that effortlessly assist them throughout their normal course of work,” said Scott Stevenson, cofounder and CEO. “It’s clear that AI will fundamentally transform every industry, and the explosive demand we’ve seen for Spellbook made it obvious that our approach has caught on.”

Tamara Steffens, managing director at Thomson Reuters Ventures, said that this investment is consistent with her fund’s committment to investing in technology to help accelerate innovation in the applications of generative AI.

“We’re excited to invest in Spellbook and support its work driving productivity in the legal sector,” Steffens said. “Thomson Reuters plans to explore the application of Spellbook’s generative AI technology to our industry leading, authoritative content to deliver customer value.”

The company said that Spellbook is currently being used by more than 600 legal teams, and another 53,000 potential customers have signed up for the waitlist.

“This funding will propel Spellbook forward rapidly,” Stevenson wrote in a blog post. “We will be doubling the size of our team this year. We’ll be hiring engineers, AI experts, lawyers and product specialists to help onboard our waitlist. …

“Most importantly, this will mean speeding innovation and the development of extensive new functionality for our customers.”