{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-24-011252","form_type":"8-K","ticker":"MKTX","cik":"0001278021","company_name":"MARKETAXESS HOLDINGS INC","filed_at":"2024-01-19T23:59:59+00:00","discovered_at":"2026-05-14T18:03:23.660182+00:00","generated_at":"2026-06-06T21:06:23.790282+00:00","sec_items":["5.02"],"event_type":"leadership","sentiment":"neutral","materiality_score":0.65,"calibrated_materiality_score":0.65,"confidence":"high","headline":"MarketAxess CFO Gerosa resigns; CEO Concannon named interim CFO effective Feb 1, 2024","bullets":["CFO Christopher N. Gerosa resigns effective Jan 31, 2024, to accept a position at another company.","CEO Christopher R. Concannon appointed interim CFO effective Feb 1, 2024, serving as both CEO and interim CFO.","Michael R. Cianciulli, Head of External Reporting, appointed interim principal accounting officer.","Board actively conducting a formal search for a permanent CFO."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-24-011252","json":"https://secwatch.observer/filing/0001193125-24-011252.json","markdown":"https://secwatch.observer/filing/0001193125-24-011252.md","text":"https://secwatch.observer/filing/0001193125-24-011252.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1278021/000119312524011252/0001193125-24-011252-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1278021/000119312524011252/d646030d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-06T21:06:23.790282+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":"351329196a","claim":"Christopher R. Concannon was appointed as interim Chief Financial Officer at MARKETAXESS HOLDINGS INC.","evidence_excerpt":"On January 18, 2024, the Board of Directors (“Board”) of the Company appointed Christopher R. Concannon, Chief Executive Officer of the Company, as interim Chief Financial Officer, effective February 1, 2024.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/1278021/000119312524011252/0001193125-24-011252-index.htm","confidence":0.95,"family_label":"Executive change","details":[{"label":"Action","value":"appointed"},{"label":"Role","value":"interim Chief Financial Officer"}],"fact_type":"executive_change"},{"claim_id":"5ae7c079ee","claim":"Michael R. Cianciulli was appointed as interim principal accounting officer at MARKETAXESS HOLDINGS INC.","evidence_excerpt":"In addition, on January 18, 2024, the Board appointed Michael R. Cianciulli, the Company’s Head of External Reporting, as interim principal accounting officer of the Company.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/1278021/000119312524011252/0001193125-24-011252-index.htm","confidence":0.95,"family_label":"Executive change","details":[{"label":"Action","value":"appointed"},{"label":"Role","value":"interim principal accounting officer"}],"fact_type":"executive_change"},{"claim_id":"cb4ea3e69c","claim":"Christopher N. Gerosa resigned as Chief Financial Officer at MARKETAXESS HOLDINGS INC.","evidence_excerpt":"On November 6, 2023, MarketAxess Holdings Inc. (the “Company”) was informed by Christopher N. Gerosa, the Company’s Chief Financial Officer, that he will resign from such position effective January 31, 2024, to accept a position with another company.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/1278021/000119312524011252/0001193125-24-011252-index.htm","confidence":0.95,"family_label":"Executive change","details":[{"label":"Action","value":"resigned"},{"label":"Role","value":"Chief Financial Officer"}],"fact_type":"executive_change"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}