---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-24-284167"
form_type: "8-K"
ticker: "ATRA"
cik: "0001604464"
company_name: "Atara Biotherapeutics, Inc."
filed_at: "2024-12-23T23:59:59+00:00"
generated_at: "2026-05-28T23:37:08.145063+00:00"
event_type: "other"
sentiment: "neutral"
materiality_score: 0.3
calibrated_materiality_score: 0.3
confidence: "high"
source: SEC EDGAR
---

# Atara Biotherapeutics adopts Third Amended and Restated Bylaws with governance changes

## Summary
- Board approved revised bylaws effective Dec 20, 2024; includes rights to postpone/cancel special stockholder meetings.
- Grants Board exclusive use of white proxy card; enhances chair's authority over meeting conduct.
- Tightens disclosure and procedural requirements for stockholder proposals and director nominations.
- Adds severability clause and other administrative updates.

## SEC filing metadata
- accession: 0001193125-24-284167
- form_type: 8-K
- ticker: ATRA
- cik: 0001604464
- company_name: Atara Biotherapeutics, Inc.
- filed_at: 2024-12-23T23:59:59+00:00
- event_type: other
- sentiment: neutral
- materiality_score: 0.3
- calibrated_materiality_score: 0.3
- confidence: high
- sec_items: 5.03, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1604464/000119312524284167/0001193125-24-284167-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1604464/000119312524284167/d480921d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-24-284167
- JSON: https://secwatch.observer/filing/0001193125-24-284167.json
- Plain text: https://secwatch.observer/filing/0001193125-24-284167.txt

## Key facts
- Governance Changes
  Atara Biotherapeutics, Inc.: Board approved Third Amended and Restated Bylaws with principal revisions including additional rights to postpone/reschedule special meetings, exclusive use of white proxy card for the Board, meeting conduct rules, stockholder proposal disclosure and procedural requirements, director eligibility req (effective 2024-12-20).
  - Change: bylaw amendment
  - Effective: 2024-12-20
  source text: On December 20, 2024, the Board of Directors (the “ Board ”) of Atara Biotherapeutics, Inc., a Delaware corporation (the “ Company ”), approved the amendment and restatement of the Bylaws of the Company (the “ Third Amended and Restated Bylaws ”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/1604464/000119312524284167/0001193125-24-284167-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.