Corporate Lawyer Builds $555M Legal AI Startup Without Coding

A general counsel who never learned to code has built one of the fastest-growing legal AI startups by solving problems she encountered firsthand during two decades in corporate law.

Cecilia Ziniti founded GC AI in November 2023 after leaving her role as general counsel at coding startup Replit. The San Mateo-based company now serves approximately 2,100 corporate clients and reached a $555 million valuation in its most recent funding round, according to Crunchbase News, which first reported the details.

From legal work to AI products

Ziniti's path to founding a venture-backed software company began when she gained early access to OpenAI's GPT technology through Replit's partnership with the AI lab in late 2021 and early 2022. This exposure came before ChatGPT's public release.

While teaching classes on using ChatGPT for legal work, Ziniti identified a critical gap. General-purpose AI tools produced responses that covered relevant legal issues but lacked the precision, sourcing, and professional tone that lawyers require. In one instance, she used ChatGPT to research legal considerations for entering the Brazilian market. The response included accurate information but opened with casual language about surfboards in Rio.

These observations became product requirements. Ziniti partnered with Bardia Pourvakil, an engineer from Replit who had once been admitted to Stanford Law School but chose engineering instead. She would teach morning classes and spend afternoons telling Pourvakil what the software needed: accurate citations, clear sourcing within documents, and appropriate professional language.

Building for in-house legal teams

GC AI focuses specifically on corporate legal departments rather than law firms, a distinction that shapes its product design. The company's contract analysis tool, for example, examines a company's own documents rather than materials from thousands of clients.

The startup has grown 400 percent year over year and counts Lockheed Martin, Time, Eventbrite, Vercel, and Gusto among its customers. Nearly 30 percent of its seats are used by employees outside legal departments, including HR and finance executives.

Ziniti's legal background proved essential for addressing trust concerns. About one-third of GC AI's 125 employees are lawyers. The company pursued SOC 2 compliance early, built data-isolation protections, and does not train its models on customers' confidential information.

Funding and growth trajectory

GC AI has raised nearly $72 million across three rounds. The most recent $60 million Series B was co-led by Scale Venture Partners and Northzone, with participation from Sound Ventures, Aglaé Ventures, SilverCircle Partners, News Corp, and The Council. Approximately 45 general counsels have also invested through a special-purpose vehicle.

Ziniti's career included legal roles at Amazon (where she was the first full-time lawyer assigned to Alexa in 2013), Cruise, robotics startup Anki, and Replit. She had also invested as an angel and served as general counsel at several venture-backed startups before raising capital herself.

Why it matters

Ziniti's success demonstrates how generative AI is enabling a new category of software founders: experienced industry practitioners who identify specific use cases for AI technology and partner with technical co-founders to build solutions. Her intimate knowledge of corporate legal work allowed her to define precise product requirements that general-purpose AI tools miss, creating defensible differentiation in a crowded market. The company's rapid growth and high valuation suggest that domain expertise may be as valuable as technical skills when building vertical AI applications.

The details were first reported by Crunchbase News.