Litigation AI startup founded by former City lawyer raises $2.5m

A litigation AI startup co-founded by a former City lawyer has raised a $2.5 million seed round as it expands into the US market.

London-based Crimson was founded by former litigator Mark Feldner, whose background includes stints at Clifford Chance and Willkie, alongside two AI engineers. The company announced the funding alongside the launch of a New York office.

Crimson joined A&O Shearman’s legal tech incubator Fuse last year, which is designed to help startups develop products alongside the firm’s lawyers and clients.

The seed round included participation from Y Combinator, alongside venture capital investors, as well as partners and arbitrators from major law firms.

The startup said its platform is already being used on disputes worth more than $40 billion and that revenue has grown more than 30% month-on-month throughout 2026. Crimson said it is working with Magic Circle firms, top US firms and specialist disputes boutiques.

Litigation focus

The startup positions itself as a litigation-native AI platform designed specifically for disputes and arbitration work.

“Litigation and arbitration matters require a level of factual, procedural, and strategic context that generic AI tools are not designed to handle,” said co-founder and chief executive Mark Feldner.

“Crimson is built specifically for litigators, giving them a faster and more reliable way to understand the case file, assess the evidence, and produce high-quality work grounded in the full matter context.”

The platform connects to case materials including pleadings, correspondence, witness evidence, expert reports and procedural documents. Crimson said its system is designed to help lawyers generate chronologies, compare party positions, track deadlines and draft documents grounded in the underlying case record.

New York is calling

As part of its US expansion, Crimson has opened a New York office led by Rhick Bose, a former litigator at Patterson Belknap and WilmerHale.

“The demand we are seeing in the US is incredible,” said Bose. “Litigation teams are dealing with larger records, tighter timelines and more pressure to deliver outstanding work efficiently. Crimson is purpose-built for that environment”.

In addition to expanding in the US market, the funding will go toward product, engineering and customer teams, as well as “deeper integrations” with law firm systems.