{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-26-045649","form_type":"8-K","ticker":"UPB","cik":"0002022626","company_name":"Upstream Bio, Inc.","filed_at":"2026-02-11T23:59:59+00:00","discovered_at":"2026-05-14T18:02:37.015834+00:00","generated_at":"2026-05-16T03:24:27.073443+00:00","sec_items":["2.02","7.01","9.01"],"event_type":"other_material","sentiment":"neutral","materiality_score":0.65,"calibrated_materiality_score":0.65,"confidence":"low","headline":"Upstream Bio reports preliminary cash of $341.5M; Phase 2 VALIANT top-line data released","bullets":["Preliminary unaudited cash, cash equivalents and short-term investments of $341.5M as of Dec 31, 2025.","Top-line results from Phase 2 VALIANT trial of verekitug in severe asthma presented in webcast; details in investor presentation.","Year-end 2025 financial close not yet completed; full results to be included in Form 10-K."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-26-045649","json":"https://secwatch.observer/filing/0001193125-26-045649.json","markdown":"https://secwatch.observer/filing/0001193125-26-045649.md","text":"https://secwatch.observer/filing/0001193125-26-045649.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/2022626/000119312526045649/0001193125-26-045649-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/2022626/000119312526045649/d103888d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-16T03:24:27.073443+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":[],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}