{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-23-064961","form_type":"8-K","ticker":"BIIB","cik":"0000875045","company_name":"BIOGEN INC.","filed_at":"2023-03-09T23:59:59+00:00","discovered_at":"2026-05-14T18:03:48.344934+00:00","generated_at":"2026-06-18T08:05:22.124310+00:00","sec_items":["5.02","8.01"],"event_type":"leadership","sentiment":"neutral","materiality_score":0.4,"calibrated_materiality_score":0.4,"confidence":"high","headline":"Biogen Chair Stelios Papadopoulos to step down; Caroline D. Dorsa elected as new Chair","bullets":["Stelios Papadopoulos will not stand for re-election at the 2023 Annual Meeting; departure unrelated to any disagreement with Board or Company.","Board elected Caroline D. Dorsa to serve as Chair of the Board, effective after the Annual Meeting.","Papadopoulos' decision is a planned succession; no operational or policy disputes cited."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-23-064961","json":"https://secwatch.observer/filing/0001193125-23-064961.json","markdown":"https://secwatch.observer/filing/0001193125-23-064961.md","text":"https://secwatch.observer/filing/0001193125-23-064961.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/875045/000119312523064961/0001193125-23-064961-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/875045/000119312523064961/d446055d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-18T08:05:22.124310+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"}