Bermudian-based White Mountains Insurance Group Ltd has announced that Ark Insurance Holdings Ltd, its specialty property and casualty reinsurance and insurance subsidiary, has renewed Outrigger Re Ltd for business incepted during calendar year 2025.

In a filing with the US Securities and Exchange Commission, White Mountains reported that the renewal is on similar terms as were in effect for calendar year 2024.

Outrigger, a reinsurance sidecar, has again entered into a quota share with Ark to provide collateralised reinsurance protection on a portion of Ark Bermuda’s global property catastrophe portfolio beginning on January 1, 2025.

Outrigger received $230 million of total investor capital for January 1, including $150 million from White Mountains.

The remaining capital was provided by continuing third-party investors, the filing said.