{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-26-255467","form_type":"8-K","ticker":"CTMX","cik":"0001501989","company_name":"CytomX Therapeutics, Inc.","filed_at":"2026-06-03T20:15:15+00:00","discovered_at":"2026-06-03T20:16:00.200265+00:00","generated_at":"2026-06-03T20:44:07.285201+00:00","sec_items":["1.01"],"event_type":"other_material","sentiment":"positive","materiality_score":0.75,"calibrated_materiality_score":0.75,"confidence":"high","headline":"CytomX and Regeneron expand collaboration; CytomX to receive $37M in target nomination payments","bullets":["Amendment No. 4 adds up to eight new collaboration programs; Regeneron nominates first two.","CytomX receives $37M aggregate target nomination payments for the two nominated programs.","Total potential milestones under expanded agreement are up to approximately $4 billion.","Royalty rates on global net sales unchanged; program selection period extended."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-26-255467","json":"https://secwatch.observer/filing/0001193125-26-255467.json","markdown":"https://secwatch.observer/filing/0001193125-26-255467.md","text":"https://secwatch.observer/filing/0001193125-26-255467.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1501989/000119312526255467/0001193125-26-255467-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1501989/000119312526255467/d66030d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-03T20:44:07.285201+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":"13c6864d40bfd8db394db21fc67932cf3d86491e","claim":"CytomX Therapeutics, Inc. amended Amendment No. 4 with Regeneron Pharmaceuticals, Inc. valued at Total potential target nomination payments and preclinical, clinical, regulatory and commercial mile (effective 2026-05-31).","evidence_excerpt":"On May 29, 2026, the Company and Regeneron entered into Amendment No. 4 to the Agreement (“Amendment No. 4”), effective May 31, 2026","evidence_source":"SEC 8-K Item 1.01/1.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/1501989/000119312526255467/0001193125-26-255467-index.htm","confidence":0.9,"family_label":"Material Agreements","details":[{"label":"Action","value":"amendment"},{"label":"Agreement","value":"collaboration"},{"label":"Counterparty","value":"Regeneron Pharmaceuticals, Inc."},{"label":"Value","value":"Total potential target nomination payments and preclinical, clinical, regulatory and commercial mile"},{"label":"Effective","value":"2026-05-31"}],"fact_type":"material_agreement"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}