{"schema_version":"secwatch.filing_event.v1","accession":"0000950170-24-134339","form_type":"8-K","ticker":"KOP","cik":"0001315257","company_name":"Koppers Holdings Inc.","filed_at":"2024-12-09T23:59:59+00:00","discovered_at":"2026-05-14T18:03:08.060662+00:00","generated_at":"2026-05-29T05:33:27.060461+00:00","sec_items":["5.02"],"event_type":"leadership","sentiment":"neutral","materiality_score":0.35,"calibrated_materiality_score":0.35,"confidence":"high","headline":"Koppers SVP & Chief Sustainability Officer Leslie Hyde to retire; transition to Assistant to CEO until March 2025","bullets":["Leslie S. Hyde, SVP & Chief Sustainability Officer of Koppers Inc., will retire effective March 31, 2025.","Effective December 9, 2024, Hyde vacates current role and serves as Assistant to the CEO through retirement.","Transition is part of a managed plan; no replacement named in the filing."],"urls":{"canonical":"https://secwatch.observer/filing/0000950170-24-134339","json":"https://secwatch.observer/filing/0000950170-24-134339.json","markdown":"https://secwatch.observer/filing/0000950170-24-134339.md","text":"https://secwatch.observer/filing/0000950170-24-134339.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1315257/000095017024134339/0000950170-24-134339-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1315257/000095017024134339/kop-20241205.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-29T05:33:27.060461+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"}