{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-25-100859","form_type":"8-K","ticker":null,"cik":"0002040807","company_name":"Metsera, Inc.","filed_at":"2025-04-28T23:59:59+00:00","discovered_at":"2026-05-14T18:02:50.765435+00:00","generated_at":"2026-05-23T05:17:35.112460+00:00","sec_items":["5.02","7.01"],"event_type":"leadership","sentiment":"neutral","materiality_score":0.5,"calibrated_materiality_score":0.5,"confidence":"high","headline":"Metsera appoints Jon Stonehouse to Board and Matt Lang as Chief Legal Officer","bullets":["Jon P. Stonehouse appointed to Board (Class III) and Audit Committee effective April 28, 2025.","Matthew Lang appointed Chief Legal Officer and Secretary; previously CBO/CLO at Lyell Immunopharma.","Stonehouse receives option award vesting in 36 equal monthly installments under director comp plan.","Stonehouse is CEO of BioCryst Pharmaceuticals; brings M&A and pharma leadership experience.","Lang's background includes executive roles at Myovant Sciences and Gilead Sciences."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-25-100859","json":"https://secwatch.observer/filing/0001193125-25-100859.json","markdown":"https://secwatch.observer/filing/0001193125-25-100859.md","text":"https://secwatch.observer/filing/0001193125-25-100859.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/2040807/000119312525100859/0001193125-25-100859-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/2040807/000119312525100859/d116647d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-23T05:17:35.112460+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":"9913a84edc","claim":"Jon P. Stonehouse was appointed as Director at Metsera, Inc..","evidence_excerpt":"On April 28, 2025, the Board of Directors (the “Board”) of Metsera, Inc. (the “Company”) appointed Jon P. Stonehouse to the Company’s Board, effective immediately.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/2040807/000119312525100859/0001193125-25-100859-index.htm","confidence":0.95,"family_label":"Executive change","details":[{"label":"Action","value":"appointed"},{"label":"Role","value":"Director"}],"fact_type":"executive_change"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}