{"schema_version":"secwatch.filing_event.v1","accession":"0001104659-23-033374","form_type":"8-K","ticker":null,"cik":"0001839185","company_name":"Summit Healthcare Acquisition Corp.","filed_at":"2023-03-16T23:59:59+00:00","discovered_at":"2026-05-14T18:03:47.023067+00:00","generated_at":"2026-06-18T00:58:14.068331+00:00","sec_items":["2.01","3.01","3.03","5.01","5.02","9.01"],"event_type":"m_and_a","sentiment":"neutral","materiality_score":0.9,"calibrated_materiality_score":0.9,"confidence":"high","headline":"Summit Healthcare completes de-SPAC merger with YS Biopharma; shares begin trading March 17","bullets":["Business combination closed March 16, 2023; YS Biopharma Ordinary Shares and Warrants to trade under YS and YSBPW.","19,388,769 Summit Class A shares redeemed at ~$10.10/share, totaling ~$195.8M in redemptions.","SPAC Class A exchange ratio of 1.4286; up to 1,708,497 YS Biopharma shares issued to non-redeeming holders.","All Summit directors and officers resigned; Yi Zhang (YS Biopharma chairman) becomes sole director of surviving entity.","Summit's securities delisted from Nasdaq; Form 25 filed; deregistration to follow."],"urls":{"canonical":"https://secwatch.observer/filing/0001104659-23-033374","json":"https://secwatch.observer/filing/0001104659-23-033374.json","markdown":"https://secwatch.observer/filing/0001104659-23-033374.md","text":"https://secwatch.observer/filing/0001104659-23-033374.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1839185/000110465923033374/0001104659-23-033374-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1839185/000110465923033374/tm239524d2_8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-18T00:58:14.068331+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":"0ee1941f47","claim":"Ken Poon departed as Director at Summit Healthcare Acquisition Corp..","evidence_excerpt":"each of Bo Tan, Ken Poon, Ian Stone, Thomas 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Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}