{"schema_version":"secwatch.filing_event.v1","accession":"0000860413-25-000155","form_type":"8-K","ticker":"FIBK","cik":"0000860413","company_name":"FIRST INTERSTATE BANCSYSTEM INC","filed_at":"2025-10-16T23:59:59+00:00","discovered_at":"2026-05-14T18:02:42.382774+00:00","generated_at":"2026-05-17T03:38:51.992207+00:00","sec_items":["7.01","9.01"],"event_type":"other_material","sentiment":"neutral","materiality_score":0.6,"calibrated_materiality_score":0.6,"confidence":"high","headline":"First Interstate selling 11 Nebraska branches to Security First; ~$280M deposits, ~$70M loans","bullets":["Security First Bank acquiring 11 Nebraska branches from First Interstate Bank under purchase and assumption agreement.","Branches had ~$280M in deposits and ~$70M in outstanding loans as of Sept. 30, 2025.","Transaction subject to regulatory approval; expected to close in early 2026.","First Interstate cites opportunity to redeploy capital toward stronger markets.","Security First will expand to 34 full-service Nebraska branches post-acquisition."],"urls":{"canonical":"https://secwatch.observer/filing/0000860413-25-000155","json":"https://secwatch.observer/filing/0000860413-25-000155.json","markdown":"https://secwatch.observer/filing/0000860413-25-000155.md","text":"https://secwatch.observer/filing/0000860413-25-000155.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/860413/000086041325000155/0000860413-25-000155-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/860413/000086041325000155/fibk-20251016.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-17T03:38:51.992207+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"}