{"filing":{"accession_number":"0001193125-26-428367","cik":"0001776111","ticker":"MBX","company_name":"MBX Biosciences, Inc.","form":"8-K","filing_date":"2026-10-22","report_date":"2026-10-20","primary_document":"mbx-20261020.htm","primary_document_url":"https://www.sec.gov/Archives/edgar/data/1776111/000119312526428367/mbx-20261020.htm"},"events":[{"id":37066,"run_id":34166,"accession_number":"0001193125-26-428367","anchor_item_number":"5.02","event_type":"exec_appointment","event_domain":"governance","is_material":true,"confidence":0.95,"summary":"The filing discloses the appointment of Peter Radovich as a director of MBX Biosciences effective October 20, 2026, upon recommendation of the Nominating and Corporate Governance Committee. While the disclosure includes compensatory details (stock option grant and cash compensation), the principal disclosed action is the appointment itself—a person taking a board role. This is material as it affects the composition and governance of the company's board of directors.","company_name":"MBX Biosciences, Inc.","ticker":"MBX","filing_date":"2026-10-22","form":"8-K","submitted_at":null,"items":[{"id":41655,"accession_number":"0001193125-26-428367","item_number":"5.02","item_title":"Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.","event_type":"exec_appointment","event_domain":"governance","is_material":true,"confidence":0.95,"reasoning":"The filing discloses the appointment of Peter Radovich as a director of MBX Biosciences effective October 20, 2026, upon recommendation of the Nominating and Corporate Governance Committee. While the disclosure includes compensatory details (stock option grant and cash compensation), the principal disclosed action is the appointment itself—a person taking a board role. This is material as it affects the composition and governance of the company's board of directors.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-10-22T12:12:36.777918+00:00","company_name":"","ticker":null,"filing_date":""}]}],"classifications":[{"id":41655,"accession_number":"0001193125-26-428367","item_number":"5.02","item_title":"Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.","event_type":"exec_appointment","event_domain":"governance","is_material":true,"confidence":0.95,"reasoning":"The filing discloses the appointment of Peter Radovich as a director of MBX Biosciences effective October 20, 2026, upon recommendation of the Nominating and Corporate Governance Committee. While the disclosure includes compensatory details (stock option grant and cash compensation), the principal disclosed action is the appointment itself—a person taking a board role. This is material as it affects the composition and governance of the company's board of directors.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-10-22T12:12:36.777918+00:00","company_name":"MBX Biosciences, Inc.","ticker":"MBX","filing_date":"2026-10-22"}]}