Ledgebrook raises $200M co-led by Allianz X and Rockefeller Capital Management to scale its AI-native specialty insurance platform

Ledgebrook has raised $200 million in primary equity financing co-led by Allianz X, the strategic investment arm of the Allianz Group, and Rockefeller Capital Management, with existing and new investors participating. Separately, Allianz Re has agreed a multi-year reinsurance agreement with the company.

Founded in Boston in 2022 by CEO Gage Caligaris, a Harvard mathematician and actuary, Ledgebrook writes general liability, professional liability and specialty cover for mid-sized businesses in the US excess and surplus market, distributed exclusively through wholesale brokers. Its in-house platform, Blackbird, reads submissions, classifies risk and calculates a technical price, with underwriters making the final call.

The company is on track to pass $1 billion in cumulative premium written since it started writing business in 2023. In August AM Best rated its carrier A- (Excellent), completing its move to a full-stack insurer. It employs around 300 people, including about 80 underwriters and 50 engineers.