{"schema_version":"secwatch.filing_event.v1","accession":"0000776867-23-000018","form_type":"8-K","ticker":"WTM","cik":"0000776867","company_name":"WHITE MOUNTAINS INSURANCE GROUP LTD","filed_at":"2023-12-21T23:59:59+00:00","discovered_at":"2026-05-14T18:03:31.987169+00:00","generated_at":"2026-06-07T09:36:06.304504+00:00","sec_items":["8.01","9.01"],"event_type":"other_material","sentiment":"positive","materiality_score":0.65,"calibrated_materiality_score":0.65,"confidence":"high","headline":"White Mountains renews $250M Outrigger Re sidecar; WTM commits $130M for 2024","bullets":["Outrigger Re Ltd. renewed on similar terms as 2023 for Ark's global property catastrophe portfolio starting Jan 1, 2024.","Total investor capital: $250M, including $130M from White Mountains and remaining from new/continuing third-party investors.","Management cites new investor interest as recognition of Ark's strong execution in the ongoing hard market."],"urls":{"canonical":"https://secwatch.observer/filing/0000776867-23-000018","json":"https://secwatch.observer/filing/0000776867-23-000018.json","markdown":"https://secwatch.observer/filing/0000776867-23-000018.md","text":"https://secwatch.observer/filing/0000776867-23-000018.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/776867/000077686723000018/0000776867-23-000018-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/776867/000077686723000018/wtm-20231221.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-07T09:36:06.304504+00:00"},"review":{"review_status":"machine_generated","human_reviewed":false,"corrected":false,"correction_note":null,"correction_timestamp":null,"superseded_by":null,"related_filings":[]},"source_grounded_claims":[],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}