{"schema_version":"secwatch.filing_event.v1","accession":"0000950170-25-069198","form_type":"8-K","ticker":"ATRA","cik":"0001604464","company_name":"Atara Biotherapeutics, Inc.","filed_at":"2025-05-12T23:59:59+00:00","discovered_at":"2026-05-14T18:02:48.982867+00:00","generated_at":"2026-05-21T23:41:12.259341+00:00","sec_items":["2.05"],"event_type":"other_material","sentiment":"negative","materiality_score":0.7,"calibrated_materiality_score":0.7,"confidence":"high","headline":"Atara Biotherapeutics reduces workforce by ~30% to retain ~23 employees","bullets":["Approximately 30% workforce reduction, retaining ~23 employees; expected completion by August 2025.","Expected severance and related costs of $1.4 million in one-time cash charges.","Additional details to be provided in the Q2 2025 10-Q filing."],"urls":{"canonical":"https://secwatch.observer/filing/0000950170-25-069198","json":"https://secwatch.observer/filing/0000950170-25-069198.json","markdown":"https://secwatch.observer/filing/0000950170-25-069198.md","text":"https://secwatch.observer/filing/0000950170-25-069198.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1604464/000095017025069198/0000950170-25-069198-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1604464/000095017025069198/atra-20250512.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-21T23:41:12.259341+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":"dd13faf4737f8048e270a5a3c617b21756cdf082","claim":"Atara Biotherapeutics, Inc. announced a restructuring with charges of approximately $1.4 million (approximately 30% of its current employees).","evidence_excerpt":"to executing on the Company’s strategic priorities. The Company expects to complete the workforce reduction by August 2025. The Company expects to recognize approximately $1.4 million for severance and related benefits for employees laid off under the reduction in force. These charges are primarily one-time termination benefits and are primarily cash charges.","evidence_source":"SEC 8-K Item 2.05/2.06","evidence_url":"https://www.sec.gov/Archives/edgar/data/1604464/000095017025069198/0000950170-25-069198-index.htm","confidence":0.9,"family_label":"Restructurings & Charges","details":[{"label":"Type","value":"restructuring"},{"label":"Charge","value":"approximately $1.4 million"},{"label":"Headcount","value":"approximately 30% of its current employees"}],"fact_type":"restructuring_charge"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}