{"filing":{"accession_number":"0001104659-26-109201","cik":"0001918102","ticker":"FISN","company_name":"DEEP FISSION, INC.","form":"8-K","filing_date":"2026-09-21","report_date":"2026-09-21","primary_document":"tm2625786d1_8k.htm","primary_document_url":"https://www.sec.gov/Archives/edgar/data/1918102/000110465926109201/tm2625786d1_8k.htm"},"events":[{"id":33931,"run_id":31236,"accession_number":"0001104659-26-109201","anchor_item_number":"7.01","event_type":"operational_other","event_domain":"operational","is_material":true,"confidence":0.75,"summary":"Deep Fission announced a collaboration with Youngquist Brothers to evaluate and test drilling and borehole-construction methods for its underground reactor deployment model. This is a material operational/strategic partnership that advances the company's core technology development toward commercial deployment targeted for 2027. While the collaboration itself is not a completed M\u0026A transaction, it represents a significant operational milestone in the company's path to commercialization and would affect a reasonable investor's assessment of execution risk and technical feasibility.","company_name":"DEEP FISSION, INC.","ticker":"FISN","filing_date":"2026-09-21","form":"8-K","submitted_at":null,"items":[{"id":37527,"accession_number":"0001104659-26-109201","item_number":"7.01","item_title":"Regulation FD Disclosure.","event_type":"operational_other","event_domain":"operational","is_material":true,"confidence":0.75,"reasoning":"Deep Fission announced a collaboration with Youngquist Brothers to evaluate and test drilling and borehole-construction methods for its underground reactor deployment model. This is a material operational/strategic partnership that advances the company's core technology development toward commercial deployment targeted for 2027. While the collaboration itself is not a completed M\u0026A transaction, it represents a significant operational milestone in the company's path to commercialization and would affect a reasonable investor's assessment of execution risk and technical feasibility.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-09-21T15:27:41.220370+00:00","company_name":"","ticker":null,"filing_date":""}]}],"classifications":[{"id":37527,"accession_number":"0001104659-26-109201","item_number":"7.01","item_title":"Regulation FD Disclosure.","event_type":"operational_other","event_domain":"operational","is_material":true,"confidence":0.75,"reasoning":"Deep Fission announced a collaboration with Youngquist Brothers to evaluate and test drilling and borehole-construction methods for its underground reactor deployment model. This is a material operational/strategic partnership that advances the company's core technology development toward commercial deployment targeted for 2027. While the collaboration itself is not a completed M\u0026A transaction, it represents a significant operational milestone in the company's path to commercialization and would affect a reasonable investor's assessment of execution risk and technical feasibility.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-09-21T15:27:41.220370+00:00","company_name":"DEEP FISSION, INC.","ticker":"FISN","filing_date":"2026-09-21"}]}