{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-23-139427","form_type":"8-K","ticker":null,"cik":"0001962918","company_name":"ACELYRIN, Inc.","filed_at":"2023-05-09T23:59:59+00:00","discovered_at":"2026-05-14T18:03:41.631130+00:00","generated_at":"2026-06-15T10:30:04.155223+00:00","sec_items":["5.03","8.01","9.01"],"event_type":"other_material","sentiment":"positive","materiality_score":0.85,"calibrated_materiality_score":0.85,"confidence":"high","headline":"ACELYRIN closes upsized IPO, raises $621M; shares begin trading on Nasdaq","bullets":["Closed IPO of 34,500,000 shares at $18.00 per share, including full exercise of underwriters' option for 4,500,000 additional shares.","Gross proceeds of $621.0 million before underwriting discounts and expenses.","Shares began trading on Nasdaq Global Select Market on May 5, 2023 under ticker SLRN.","Joint book-running managers: Morgan Stanley, Jefferies, TD Cowen, and Piper Sandler."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-23-139427","json":"https://secwatch.observer/filing/0001193125-23-139427.json","markdown":"https://secwatch.observer/filing/0001193125-23-139427.md","text":"https://secwatch.observer/filing/0001193125-23-139427.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1962918/000119312523139427/0001193125-23-139427-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1962918/000119312523139427/d444368d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-15T10:30:04.155223+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":"0f958c206a8548accc1f5c6872fce05725fc5443","claim":"ACELYRIN, Inc.: Filed amended and restated certificate of incorporation in connection with IPO closing, effective upon closing of the IPO (effective 2023-05-09).","evidence_excerpt":"the Company filed an amended and restated certificate of incorporation (the “Restated Certificate”) with the Secretary of State of the State of Delaware","evidence_source":"SEC 8-K Item 5.03/5.05/5.06","evidence_url":"https://www.sec.gov/Archives/edgar/data/1962918/000119312523139427/0001193125-23-139427-index.htm","confidence":0.9,"family_label":"Governance Changes","details":[{"label":"Change","value":"charter amendment"},{"label":"Effective","value":"2023-05-09"}],"fact_type":"governance_change"},{"claim_id":"270d66804c58e8dcddc1cda43032f9f475a1a5a1","claim":"ACELYRIN, Inc.: Adopted amended and restated bylaws effective upon IPO closing (effective 2023-05-09).","evidence_excerpt":"Effective as of May 9, 2023, the Company adopted amended and restated bylaws (the “Restated Bylaws”) in connection with the closing of the IPO","evidence_source":"SEC 8-K Item 5.03/5.05/5.06","evidence_url":"https://www.sec.gov/Archives/edgar/data/1962918/000119312523139427/0001193125-23-139427-index.htm","confidence":0.9,"family_label":"Governance Changes","details":[{"label":"Change","value":"bylaw amendment"},{"label":"Effective","value":"2023-05-09"}],"fact_type":"governance_change"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}