White Mountains Insurance Group Ltd, the Bermuda-domiciled financial services holding company, has agreed to acquire a majority stake in Bamboo Ide8 Insurance Services LLC, a managing general agent focused on the California homeowners insurance market.

California-based Bamboo has a Bermudian-domiciled captive insurance entity.

The MGA said it expected to invest approximately $285 million, including primary capital to support Bamboo's growth, and to acquire approximately 70 per cent of Bamboo basic shares outstanding.

Launched in 2018 by John Chu, Bamboo provides homeowners' insurance for more than 100,000 California policyholders, using its technology-enabled underwriting platform to select and manage risk.

White Mountains said Bamboo had grown profitably and rapidly in the challenging California market and was now poised to expand into other states.

Mr Chu and the current Bamboo management team will continue to lead the business through its next phase and will retain a significant equity stake.

Chris Delehanty, head of M&A of White Mountains, said: "We are pleased to make this investment alongside John and the Bamboo management team. Bamboo is delivering a much needed insurance alternative to homeowners in California. Bamboo has strong momentum and we look forward to supporting its continued growth."

Mr Chu said: "This transaction marks a new and exciting chapter for Bamboo. We are fortunate to have found a like-minded capital partner who shares our vision and has a strong track record of successful insurance partnerships."

The transaction is expected to close in the first quarter of 2024. The closing is subject to regulatory approvals and other customary closing conditions. The closing is not subject to a financing condition.

The exact ownership to be acquired by White Mountains and the resulting amount that will be invested will be determined based on Bamboo unit holder elections made prior to closing, the company said.