Imposes safety, transparency, and accountability obligations on 'large developers' of frontier AI models — defined as persons who have trained at least one frontier model costing over $5M in compute and have spent over $100M in aggregate compute costs on frontier models. Core obligations include implementing, publishing, and annually reviewing a safety and security protocol; conducting pre-deployment safety assessments; retaining detailed testing records; reporting safety incidents to the Division of Homeland Security and Emergency Services within 72 hours; and retaining an independent third-party auditor annually. Prohibits deploying a frontier model that would create an unreasonable risk of critical harm (defined as 100+ deaths/serious injuries or $1B+ damages via CBRN weapons or autonomous criminal conduct). Includes robust whistleblower protections for employees, contractors, and unpaid advisors. Enforcement is exclusively through the Attorney General, with civil penalties up to $10M for a first violation and $30M for subsequent violations. Accredited colleges and universities engaged in academic research are exempt.