Crimson

Crimson is an AI-native case intelligence platform for litigation and arbitration lawyers, organising case files and answering questions with citations across pleadings, hearing transcripts, letters and other documents. Lawyers can ask natural-language questions such as what the opposing party has said about a given issue and receive cited answers drawn from the case record. Founded in 2025 by former Clifford Chance and WilmerHale litigator Mark Feldner and CTO David Stromback, the London-based company went through Y Combinator's spring 2025 batch. It raised a $2.5M seed round led by Y Combinator, opened a New York office, and says its platform has been used on disputes worth more than $40B.