{"schema_version":"secwatch.filing_event.v1","accession":"0001619856-24-000071","form_type":"8-K","ticker":"CRBU","cik":"0001619856","company_name":"Caribou Biosciences, Inc.","filed_at":"2024-09-03T23:59:59+00:00","discovered_at":"2026-05-14T18:03:13.827039+00:00","generated_at":"2026-05-31T06:37:57.394220+00:00","sec_items":["5.02","9.01"],"event_type":"leadership","sentiment":"negative","materiality_score":0.6,"calibrated_materiality_score":0.6,"confidence":"high","headline":"CFO Jason O'Byrne resigns effective Sept 27; Ryan Fischesser named principal accounting officer","bullets":["Jason O'Byrne resigns as CFO effective Sept 27, 2024, to pursue other opportunity; no disagreement with company.","Company has initiated search for new CFO.","Ryan Fischesser, VP Finance and Controller, will assume principal accounting officer role Sept 27.","Fischesser previously served as principal accounting officer from IPO through Dec 2022."],"urls":{"canonical":"https://secwatch.observer/filing/0001619856-24-000071","json":"https://secwatch.observer/filing/0001619856-24-000071.json","markdown":"https://secwatch.observer/filing/0001619856-24-000071.md","text":"https://secwatch.observer/filing/0001619856-24-000071.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1619856/000161985624000071/0001619856-24-000071-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1619856/000161985624000071/crbu-20240901.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-31T06:37:57.394220+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":"2e1131a0c5","claim":"Jason O'Byrne resigned as Chief Financial Officer at Caribou Biosciences, Inc..","evidence_excerpt":"On September 1, 2024, Jason O’Byrne, the Chief Financial Officer of Caribou Biosciences, Inc. (the “Company”), informed the Company of his intent to resign from his position, effective September 27, 2024, to pursue another opportunity.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/1619856/000161985624000071/0001619856-24-000071-index.htm","confidence":0.95,"family_label":"Executive change","details":[{"label":"Action","value":"resigned"},{"label":"Role","value":"Chief Financial Officer"}],"fact_type":"executive_change"},{"claim_id":"8b6bf34e26","claim":"Ryan Fischesser was appointed as principal accounting officer at Caribou Biosciences, Inc..","evidence_excerpt":"The Company intends to appoint Ryan Fischesser, the Company’s current Vice President of Finance and Controller, to assume the role of the Company’s principal accounting officer, effective as of the close of business on September 27, 2024.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/1619856/000161985624000071/0001619856-24-000071-index.htm","confidence":0.95,"family_label":"Executive change","details":[{"label":"Action","value":"appointed"},{"label":"Role","value":"principal accounting officer"}],"fact_type":"executive_change"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}