{"filing":{"accession_number":"0001193125-26-430472","cik":"0001278021","ticker":"MKTX","company_name":"MARKETAXESS HOLDINGS INC","form":"8-K","filing_date":"2026-10-23","report_date":"2026-10-23","primary_document":"d150415d8k.htm","primary_document_url":"https://www.sec.gov/Archives/edgar/data/1278021/000119312526430472/d150415d8k.htm"},"events":[{"id":37635,"run_id":34683,"accession_number":"0001193125-26-430472","anchor_item_number":"8.01","event_type":"ma_activity","event_domain":"operational","is_material":true,"confidence":0.92,"summary":"This Item 8.01 disclosure centers on supplemental disclosures related to the pending merger between MarketAxess and Intercontinental Exchange, Inc. announced on July 29, 2026. The filing addresses litigation and stockholder demands challenging proxy statement disclosures, and provides additional detail on the merger background, negotiations, and process. While technically filed under Item 8.01 (Other Events), the substance is the company's response to challenges to a material acquisition transaction and the supplemental disclosures intended to support completion of the merger.","company_name":"MARKETAXESS HOLDINGS INC","ticker":"MKTX","filing_date":"2026-10-23","form":"8-K","submitted_at":null,"items":[{"id":42411,"accession_number":"0001193125-26-430472","item_number":"8.01","item_title":null,"event_type":"ma_activity","event_domain":"operational","is_material":true,"confidence":0.92,"reasoning":"This Item 8.01 disclosure centers on supplemental disclosures related to the pending merger between MarketAxess and Intercontinental Exchange, Inc. announced on July 29, 2026. The filing addresses litigation and stockholder demands challenging proxy statement disclosures, and provides additional detail on the merger background, negotiations, and process. While technically filed under Item 8.01 (Other Events), the substance is the company's response to challenges to a material acquisition transaction and the supplemental disclosures intended to support completion of the merger.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-10-23T20:23:43.735802+00:00","company_name":"","ticker":null,"filing_date":""}]}],"classifications":[{"id":42411,"accession_number":"0001193125-26-430472","item_number":"8.01","item_title":null,"event_type":"ma_activity","event_domain":"operational","is_material":true,"confidence":0.92,"reasoning":"This Item 8.01 disclosure centers on supplemental disclosures related to the pending merger between MarketAxess and Intercontinental Exchange, Inc. announced on July 29, 2026. The filing addresses litigation and stockholder demands challenging proxy statement disclosures, and provides additional detail on the merger background, negotiations, and process. While technically filed under Item 8.01 (Other Events), the substance is the company's response to challenges to a material acquisition transaction and the supplemental disclosures intended to support completion of the merger.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-10-23T20:23:43.735802+00:00","company_name":"MARKETAXESS HOLDINGS INC","ticker":"MKTX","filing_date":"2026-10-23"}]}