{"filing":{"accession_number":"0002019804-26-000018","cik":"0002019804","ticker":"IMSRW","company_name":"Terrestrial Energy Inc. /DE/","form":"8-K","filing_date":"2026-07-28","report_date":"2026-07-23","primary_document":"tmb-20260723x8k.htm","primary_document_url":"https://www.sec.gov/Archives/edgar/data/2019804/000201980426000018/tmb-20260723x8k.htm"},"events":[{"id":21170,"run_id":19082,"accession_number":"0002019804-26-000018","anchor_item_number":"5.02","event_type":"exec_appointment","event_domain":"governance","is_material":true,"confidence":0.95,"summary":"Terrestrial Energy Inc. appointed Kathryn McCarthy to its Board of Directors effective July 22, 2026. McCarthy brings substantial nuclear industry expertise, including leadership of the US ITER Project and senior roles at national laboratories, strengthening the company's governance in advanced reactor development.","company_name":"Terrestrial Energy Inc. /DE/","ticker":"IMSRW","filing_date":"2026-07-28","form":"8-K","submitted_at":null,"items":[{"id":20732,"accession_number":"0002019804-26-000018","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 Kathryn McCarthy to the Board of Directors effective July 22, 2026. McCarthy brings substantial nuclear industry expertise, including leadership of the US ITER Project and senior roles at national laboratories. The principal disclosed action is a person taking a director role, making this an executive appointment. The appointment is material given her deep experience in nuclear technology and the company's focus on advanced reactor development.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-07-28T20:36:42.230567+00:00","company_name":"","ticker":null,"filing_date":""},{"id":20733,"accession_number":"0002019804-26-000018","item_number":"7.01","item_title":"Regulation FD Disclosure","event_type":"exec_appointment","event_domain":"governance","is_material":true,"confidence":0.95,"reasoning":"The filing discloses the appointment of Kathryn McCarthy to the Board of Directors of Terrestrial Energy Inc. The press release explicitly states \"Terrestrial Energy Board Adds Industry Veteran Kathryn McCarthy\" and details her extensive background in nuclear science and technology leadership. This is a material governance event involving the addition of a qualified director to the board, which would affect a reasonable investor's assessment of the company's leadership and strategic direction.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-07-28T20:36:42.230567+00:00","company_name":"","ticker":null,"filing_date":""}]}],"classifications":[{"id":20732,"accession_number":"0002019804-26-000018","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 Kathryn McCarthy to the Board of Directors effective July 22, 2026. McCarthy brings substantial nuclear industry expertise, including leadership of the US ITER Project and senior roles at national laboratories. The principal disclosed action is a person taking a director role, making this an executive appointment. The appointment is material given her deep experience in nuclear technology and the company's focus on advanced reactor development.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-07-28T20:36:42.230567+00:00","company_name":"Terrestrial Energy Inc. /DE/","ticker":"IMSRW","filing_date":"2026-07-28"},{"id":20733,"accession_number":"0002019804-26-000018","item_number":"7.01","item_title":"Regulation FD Disclosure","event_type":"exec_appointment","event_domain":"governance","is_material":true,"confidence":0.95,"reasoning":"The filing discloses the appointment of Kathryn McCarthy to the Board of Directors of Terrestrial Energy Inc. The press release explicitly states \"Terrestrial Energy Board Adds Industry Veteran Kathryn McCarthy\" and details her extensive background in nuclear science and technology leadership. This is a material governance event involving the addition of a qualified director to the board, which would affect a reasonable investor's assessment of the company's leadership and strategic direction.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-07-28T20:36:42.230567+00:00","company_name":"Terrestrial Energy Inc. /DE/","ticker":"IMSRW","filing_date":"2026-07-28"}]}