{"schema_version":"secwatch.filing_event.v1","accession":"0001104659-25-058170","form_type":"8-K","ticker":"FIBK","cik":"0000860413","company_name":"FIRST INTERSTATE BANCSYSTEM INC","filed_at":"2025-06-10T23:59:59+00:00","discovered_at":"2026-05-14T18:02:51.493876+00:00","generated_at":"2026-05-19T16:33:54.857008+00:00","sec_items":["1.01","2.03","9.01"],"event_type":"debt","sentiment":"neutral","materiality_score":0.6,"calibrated_materiality_score":0.6,"confidence":"high","headline":"First Interstate BancSystem closes $125M offering of 7.625% subordinated notes due 2035","bullets":["Completed public offering of $125M in 7.625% fixed-to-floating rate subordinated notes due 2035.","Notes initially treated as Tier 2 capital for regulatory purposes.","Interest: 7.625% fixed through June 15, 2030, then floating at 3M Term SOFR + 398 bps quarterly.","Company may redeem notes in whole/part starting June 15, 2030, or upon tax/Tier 2 capital events.","Notes are unsecured, subordinated, and structurally subordinate to liabilities of bank subsidiary."],"urls":{"canonical":"https://secwatch.observer/filing/0001104659-25-058170","json":"https://secwatch.observer/filing/0001104659-25-058170.json","markdown":"https://secwatch.observer/filing/0001104659-25-058170.md","text":"https://secwatch.observer/filing/0001104659-25-058170.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/860413/000110465925058170/0001104659-25-058170-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/860413/000110465925058170/tm258437d8_8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-19T16:33:54.857008+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":[{"claim_id":"20777287a343635824f8dd6930036c8be841fab1","claim":"FIRST INTERSTATE BANCSYSTEM INC incurred senior notes of $125,000,000 aggregate principal amount with U.S. Bank Trust Company, National Association at 7.625% Fixed-to-Floating Rate maturing 2035.","evidence_excerpt":"On June 10, 2025, First Interstate BancSystem, Inc. (the “Company”) completed its previously announced public offering of $125,000,000 aggregate principal amount of its 7.625% Fixed-to-Floating Rate Subordinated Notes due 2035","evidence_source":"SEC 8-K Item 2.03/2.04","evidence_url":"https://www.sec.gov/Archives/edgar/data/860413/000110465925058170/0001104659-25-058170-index.htm","confidence":0.9,"family_label":"Debt Financings","details":[{"label":"Instrument","value":"senior notes"},{"label":"Principal","value":"$125,000,000 aggregate principal amount"},{"label":"Counterparty","value":"U.S. Bank Trust Company, National Association"},{"label":"Rate","value":"7.625% Fixed-to-Floating Rate"},{"label":"Maturity","value":"2035"},{"label":"Event","value":"incurrence"}],"fact_type":"debt_financing"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}