{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-24-162069","form_type":"8-K","ticker":"ATRA","cik":"0001604464","company_name":"Atara Biotherapeutics, Inc.","filed_at":"2024-06-17T23:59:59+00:00","discovered_at":"2026-05-14T18:03:19.185072+00:00","generated_at":"2026-06-01T04:06:41.249475+00:00","sec_items":["8.01","9.01"],"event_type":"other_material","sentiment":"negative","materiality_score":0.6,"calibrated_materiality_score":0.6,"confidence":"high","headline":"Atara Biotherapeutics announces 1-for-25 reverse stock split to comply with Nasdaq listing requirement","bullets":["Reverse stock split at 1-for-25 ratio effective June 20, 2024 at 12:01 a.m. ET; post-split trading starts same day.","Outstanding shares reduced from ~122.6M to ~4.9M; fractional shares paid in cash.","Split authorized by stockholders on June 10, 2024; board set final ratio same day.","Purpose: regain compliance with Nasdaq $1.00 minimum bid price for continued listing.","Pre-funded warrants adjusted from 32.15M pre-split to ~1.29M post-split, subject to fractional cash payments."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-24-162069","json":"https://secwatch.observer/filing/0001193125-24-162069.json","markdown":"https://secwatch.observer/filing/0001193125-24-162069.md","text":"https://secwatch.observer/filing/0001193125-24-162069.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1604464/000119312524162069/0001193125-24-162069-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1604464/000119312524162069/d705331d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-01T04:06:41.249475+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"}