{"transactions":[{"id":4619048,"issuer":{"id":4141,"kind":"organization","name":"FIRST INTERSTATE BANCSYSTEM INC","symbol":"FIBK"},"owners":[{"id":183766,"kind":"person","name":"Lee Jeffery D.","position":1,"cik":"0002154828","reported_name":"Lee Jeffery D.","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operations Officer"}}],"security":"Common Stock","published_at":"2026-09-16T17:16:07.000Z","date":"2026-09-14","kind":"grant","planned":false,"acquired":true,"shares":5417,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Shares issuable upon vesting of restricted stock units granted to the reporting person pursuant to the Registrant's 2023 Equity and Incentive Plan. The restricted stock units vest in three equal annual installments beginning on September 14, 2027, subject to the reporting person's continued employment through each applicable vesting date."}],"balance_after":5417,"source":{"system":"sec-edgar","filing":"0002154828-26-000005","document":"wk-form4_1789578965.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/2154828/000215482826000005/wk-form4_1789578965.xml","form_type":"4"}}]}