{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-23-259403","form_type":"8-K","ticker":null,"cik":"0001827506","company_name":"Tourmaline Bio, Inc.","filed_at":"2023-10-20T23:59:59+00:00","discovered_at":"2026-05-14T18:03:30.798287+00:00","generated_at":"2026-06-09T18:52:26.039507+00:00","sec_items":["2.01","1.01","5.02","3.03","5.01","5.03","8.01","9.01"],"event_type":"m_and_a","sentiment":"neutral","materiality_score":0.95,"calibrated_materiality_score":0.95,"confidence":"high","headline":"Tourmaline Bio completes reverse merger with Talaris; 78.1% ownership to former Tourmaline holders","bullets":["Merger closed Oct. 19, 2023; Tourmaline survived as wholly owned sub, renamed Tourmaline Bio, Inc.","Reverse stock split 1-for-10 effected at 4:00 p.m. ET; new CUSIP 89157D 105.","Former Tourmaline stockholders receive ~15.9M shares (0.7977 exchange ratio, pre-split); own 78.1% of post-merger company.","New board of 7 directors: 2 from legacy Talaris, 5 from Tourmaline; Sandeep Kulkarni named CEO.","Common stock trades on Nasdaq under new ticker TRML starting Oct. 20, 2023."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-23-259403","json":"https://secwatch.observer/filing/0001193125-23-259403.json","markdown":"https://secwatch.observer/filing/0001193125-23-259403.md","text":"https://secwatch.observer/filing/0001193125-23-259403.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1827506/000119312523259403/0001193125-23-259403-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1827506/000119312523259403/d571384d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-09T18:52:26.039507+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":"00c648ab1d","claim":"Geoff MacKay resigned as Director at Tourmaline Bio, Inc..","evidence_excerpt":"Sandip Agarwala, Suzanne T. 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